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-rw-r--r--abs/core/kernel26/2.6.37.1-fix-no-more-unsigned.patch20
-rw-r--r--abs/core/kernel26/PKGBUILD26
-rw-r--r--abs/core/kernel26/config77
-rw-r--r--abs/core/kernel26/tmp/patch-2.6.37-ck29083
4 files changed, 9140 insertions, 66 deletions
diff --git a/abs/core/kernel26/2.6.37.1-fix-no-more-unsigned.patch b/abs/core/kernel26/2.6.37.1-fix-no-more-unsigned.patch
new file mode 100644
index 0000000..f132379
--- /dev/null
+++ b/abs/core/kernel26/2.6.37.1-fix-no-more-unsigned.patch
@@ -0,0 +1,20 @@
+--- linux-2.6.37.orig/kernel/sched_bfs.c 2011-02-18 23:09:39.000000000 +0200
++++ linux-2.6.37/kernel/sched_bfs.c 2011-02-18 23:13:17.368000023 +0200
+@@ -3352,7 +3352,7 @@
+ * This waits for either a completion of a specific task to be signaled or for a
+ * specified timeout to expire. It is interruptible. The timeout is in jiffies.
+ */
+-unsigned long __sched
++long __sched
+ wait_for_completion_interruptible_timeout(struct completion *x,
+ unsigned long timeout)
+ {
+@@ -3385,7 +3385,7 @@
+ * signaled or for a specified timeout to expire. It can be
+ * interrupted by a kill signal. The timeout is in jiffies.
+ */
+-unsigned long __sched
++long __sched
+ wait_for_completion_killable_timeout(struct completion *x,
+ unsigned long timeout)
+ {
diff --git a/abs/core/kernel26/PKGBUILD b/abs/core/kernel26/PKGBUILD
index 750ed17..f5cdf77 100644
--- a/abs/core/kernel26/PKGBUILD
+++ b/abs/core/kernel26/PKGBUILD
@@ -7,26 +7,28 @@ pkgname=('kernel26' 'kernel26-headers' 'kernel26-docs') # Build stock -ARCH kern
_kernelname=${pkgname#kernel26}
_basekernel=2.6.37
pkgver=${_basekernel}
-pkgrel=6
-_archver=4
+pkgrel=9
+_archver=6
depends=('fbsplash')
makedepends=('xmlto' 'docbook-xsl')
-_patchname="patch-${pkgver}-${_archver}-ARCH"
+_patchname="patch-${pkgver}.${_archver}-1-ARCH"
#_patchname="patch-${pkgver}-1-ARCH"
_fbpatchname="4200_fbcondecor-0.9.6.patch"
-_ckpatchname="patch-2.6.37-ck1"
+_ckpatchname="patch-2.6.37-ck2"
_lhpatchname="lh.patch"
arch=(i686 x86_64)
license=('GPL2')
url="http://www.kernel.org"
source=(ftp://ftp.kernel.org/pub/linux/kernel/v2.6/linux-$_basekernel.tar.bz2
ftp://ftp.archlinux.org/other/kernel26/${_patchname}.bz2
- http://kernel.org/pub/linux/kernel/people/ck/patches/2.6/2.6.37/2.6.37-ck1/patch-2.6.37-ck1.bz2
+# http://kernel.org/pub/linux/kernel/people/ck/patches/2.6/2.6.37/2.6.37-ck1/patch-2.6.37-ck1.bz2
+ http://ompldr.org/vN2d6cg/patch-2.6.37-ck2.bz2
+ ftp://ftp.knoppmyth.net/R6/sources/sk98lin_v10.88.3.3_K2.6.37.patch
4200_fbcondecor-0.9.6.patch
# the main kernel config files
config config.x86_64 lh.patch.bz2
# standard config files for mkinitcpio ramdisk
- kernel26.preset)
+ kernel26.preset 2.6.37.1-fix-no-more-unsigned.patch)
build() {
cd ${srcdir}/linux-$_basekernel
# Add -ARCH patches
@@ -35,6 +37,8 @@ build() {
patch -Np1 -i ${srcdir}/${_fbpatchname}
patch -Np1 -i ${srcdir}/${_ckpatchname}
patch -Np1 -i ${srcdir}/${_lhpatchname}
+ patch -Np1 -i ${srcdir}/2.6.37.1-fix-no-more-unsigned.patch
+ patch -Np1 -i ${srcdir}/sk98lin_v10.88.3.3_K2.6.37.patch
if [ "$CARCH" = "x86_64" ]; then
cat ../config.x86_64 >./.config
@@ -245,10 +249,12 @@ find $pkgdir -type d -exec chmod 755 {} \;
rm -f $pkgdir/usr/src/linux-$_kernver/Documentation/DocBook/Makefile
}
md5sums=('c8ee37b4fdccdb651e0603d35350b434'
- '732176aeb134678b4e369e1d5d5fca2e'
- 'd5c93c7df1692d364c15d8eea0b384c9'
+ '2a7c0e9a9cd6bea46aa9b62f246439e2'
+ '4961070c8deebee3506df40083e84d3a'
+ 'ae26934abb7168d0f928fb91eca12d92'
'db9a807e03b7e8cfbc389089b006c7a7'
- '5b284b5a93f285abfb71efa5d6a00eb2'
+ '7a9f8e179aa3b58a31976ffb05970165'
'58990501d493d3e516a9ff58b3e0e0e7'
'c5793a80c59be4f0b54bc3b2a49e14c7'
- '25584700a0a679542929c4bed31433b6')
+ '25584700a0a679542929c4bed31433b6'
+ 'c99a13ccbba56e3516ca8907c211a27b')
diff --git a/abs/core/kernel26/config b/abs/core/kernel26/config
index 1b42cf9..08a2278 100644
--- a/abs/core/kernel26/config
+++ b/abs/core/kernel26/config
@@ -1,7 +1,7 @@
#
# Automatically generated make config: don't edit
# Linux/i386 2.6.37 Kernel Configuration
-# Wed Jan 12 03:08:44 2011
+# Fri Jul 8 05:17:19 2011
#
# CONFIG_64BIT is not set
CONFIG_X86_32=y
@@ -111,8 +111,9 @@ CONFIG_GENERIC_PENDING_IRQ=y
#
# RCU Subsystem
#
-CONFIG_TREE_PREEMPT_RCU=y
-CONFIG_PREEMPT_RCU=y
+CONFIG_TREE_RCU=y
+# CONFIG_TREE_PREEMPT_RCU is not set
+# CONFIG_PREEMPT_RCU is not set
# CONFIG_RCU_TRACE is not set
CONFIG_RCU_FANOUT=32
# CONFIG_RCU_FANOUT_EXACT is not set
@@ -248,27 +249,27 @@ CONFIG_PADATA=y
# CONFIG_INLINE_SPIN_LOCK_BH is not set
# CONFIG_INLINE_SPIN_LOCK_IRQ is not set
# CONFIG_INLINE_SPIN_LOCK_IRQSAVE is not set
-# CONFIG_INLINE_SPIN_UNLOCK is not set
+CONFIG_INLINE_SPIN_UNLOCK=y
# CONFIG_INLINE_SPIN_UNLOCK_BH is not set
-# CONFIG_INLINE_SPIN_UNLOCK_IRQ is not set
+CONFIG_INLINE_SPIN_UNLOCK_IRQ=y
# CONFIG_INLINE_SPIN_UNLOCK_IRQRESTORE is not set
# CONFIG_INLINE_READ_TRYLOCK is not set
# CONFIG_INLINE_READ_LOCK is not set
# CONFIG_INLINE_READ_LOCK_BH is not set
# CONFIG_INLINE_READ_LOCK_IRQ is not set
# CONFIG_INLINE_READ_LOCK_IRQSAVE is not set
-# CONFIG_INLINE_READ_UNLOCK is not set
+CONFIG_INLINE_READ_UNLOCK=y
# CONFIG_INLINE_READ_UNLOCK_BH is not set
-# CONFIG_INLINE_READ_UNLOCK_IRQ is not set
+CONFIG_INLINE_READ_UNLOCK_IRQ=y
# CONFIG_INLINE_READ_UNLOCK_IRQRESTORE is not set
# CONFIG_INLINE_WRITE_TRYLOCK is not set
# CONFIG_INLINE_WRITE_LOCK is not set
# CONFIG_INLINE_WRITE_LOCK_BH is not set
# CONFIG_INLINE_WRITE_LOCK_IRQ is not set
# CONFIG_INLINE_WRITE_LOCK_IRQSAVE is not set
-# CONFIG_INLINE_WRITE_UNLOCK is not set
+CONFIG_INLINE_WRITE_UNLOCK=y
# CONFIG_INLINE_WRITE_UNLOCK_BH is not set
-# CONFIG_INLINE_WRITE_UNLOCK_IRQ is not set
+CONFIG_INLINE_WRITE_UNLOCK_IRQ=y
# CONFIG_INLINE_WRITE_UNLOCK_IRQRESTORE is not set
# CONFIG_MUTEX_SPIN_ON_OWNER is not set
CONFIG_FREEZER=y
@@ -277,7 +278,7 @@ CONFIG_FREEZER=y
# Processor type and features
#
CONFIG_TICK_ONESHOT=y
-CONFIG_NO_HZ=y
+# CONFIG_NO_HZ is not set
CONFIG_HIGH_RES_TIMERS=y
CONFIG_GENERIC_CLOCKEVENTS_BUILD=y
CONFIG_SMP=y
@@ -354,9 +355,9 @@ CONFIG_NR_CPUS=8
CONFIG_SCHED_SMT=y
CONFIG_SCHED_MC=y
# CONFIG_IRQ_TIME_ACCOUNTING is not set
-# CONFIG_PREEMPT_NONE is not set
+CONFIG_PREEMPT_NONE=y
# CONFIG_PREEMPT_VOLUNTARY is not set
-CONFIG_PREEMPT=y
+# CONFIG_PREEMPT is not set
CONFIG_X86_LOCAL_APIC=y
CONFIG_X86_IO_APIC=y
CONFIG_X86_REROUTE_FOR_BROKEN_BOOT_IRQS=y
@@ -427,10 +428,10 @@ CONFIG_ARCH_USES_PG_UNCACHED=y
CONFIG_EFI=y
CONFIG_SECCOMP=y
CONFIG_CC_STACKPROTECTOR=y
-# CONFIG_HZ_100 is not set
+CONFIG_HZ_100=y
# CONFIG_HZ_250_NODEFAULT is not set
# CONFIG_HZ_300 is not set
-CONFIG_HZ_1000=y
+# CONFIG_HZ_1000 is not set
# CONFIG_HZ_1500 is not set
# CONFIG_HZ_2000 is not set
# CONFIG_HZ_3000 is not set
@@ -438,7 +439,7 @@ CONFIG_HZ_1000=y
# CONFIG_HZ_5000 is not set
# CONFIG_HZ_7500 is not set
# CONFIG_HZ_10000 is not set
-CONFIG_HZ=1000
+CONFIG_HZ=100
CONFIG_SCHED_HRTICK=y
CONFIG_KEXEC=y
# CONFIG_CRASH_DUMP is not set
@@ -512,48 +513,13 @@ CONFIG_APM_DO_ENABLE=y
#
# CPU Frequency scaling
#
-CONFIG_CPU_FREQ=y
-CONFIG_CPU_FREQ_TABLE=m
-# CONFIG_CPU_FREQ_DEBUG is not set
-CONFIG_CPU_FREQ_STAT=m
-CONFIG_CPU_FREQ_STAT_DETAILS=y
-CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE=y
+# CONFIG_CPU_FREQ is not set
+# CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE is not set
# CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE is not set
# CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND is not set
# CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE is not set
-CONFIG_CPU_FREQ_GOV_PERFORMANCE=y
-CONFIG_CPU_FREQ_GOV_POWERSAVE=m
-CONFIG_CPU_FREQ_GOV_USERSPACE=m
-CONFIG_CPU_FREQ_GOV_ONDEMAND=m
-CONFIG_CPU_FREQ_GOV_CONSERVATIVE=m
-
-#
-# CPUFreq processor drivers
-#
-CONFIG_X86_PCC_CPUFREQ=m
-CONFIG_X86_ACPI_CPUFREQ=m
-CONFIG_X86_POWERNOW_K6=m
-CONFIG_X86_POWERNOW_K7=m
-CONFIG_X86_POWERNOW_K7_ACPI=y
-CONFIG_X86_POWERNOW_K8=m
-CONFIG_X86_GX_SUSPMOD=m
-# CONFIG_X86_SPEEDSTEP_CENTRINO is not set
-CONFIG_X86_SPEEDSTEP_ICH=m
-CONFIG_X86_SPEEDSTEP_SMI=m
-CONFIG_X86_P4_CLOCKMOD=m
-CONFIG_X86_CPUFREQ_NFORCE2=m
-CONFIG_X86_LONGRUN=m
-CONFIG_X86_LONGHAUL=m
-CONFIG_X86_E_POWERSAVER=m
-
-#
-# shared options
-#
-CONFIG_X86_SPEEDSTEP_LIB=m
-CONFIG_X86_SPEEDSTEP_RELAXED_CAP_CHECK=y
CONFIG_CPU_IDLE=y
CONFIG_CPU_IDLE_GOV_LADDER=y
-CONFIG_CPU_IDLE_GOV_MENU=y
CONFIG_INTEL_IDLE=y
#
@@ -1954,10 +1920,11 @@ CONFIG_YELLOWFIN=m
CONFIG_R8169=m
# CONFIG_R8169_VLAN is not set
CONFIG_SIS190=m
+CONFIG_SK98LIN=m
+# CONFIG_SK98LIN_NAPI is not set
CONFIG_SKGE=m
# CONFIG_SKGE_DEBUG is not set
-CONFIG_SKY2=m
-# CONFIG_SKY2_DEBUG is not set
+# CONFIG_SKY2 is not set
CONFIG_VIA_VELOCITY=m
CONFIG_TIGON3=m
CONFIG_BNX2=m
@@ -5166,7 +5133,6 @@ CONFIG_TIMER_STATS=y
# CONFIG_SLUB_DEBUG_ON is not set
# CONFIG_SLUB_STATS is not set
# CONFIG_DEBUG_KMEMLEAK is not set
-# CONFIG_DEBUG_PREEMPT is not set
# CONFIG_DEBUG_RT_MUTEXES is not set
# CONFIG_RT_MUTEX_TESTER is not set
# CONFIG_DEBUG_SPINLOCK is not set
@@ -5225,7 +5191,6 @@ CONFIG_TRACING_SUPPORT=y
CONFIG_FTRACE=y
# CONFIG_FUNCTION_TRACER is not set
# CONFIG_IRQSOFF_TRACER is not set
-# CONFIG_PREEMPT_TRACER is not set
# CONFIG_SCHED_TRACER is not set
# CONFIG_FTRACE_SYSCALLS is not set
CONFIG_BRANCH_PROFILE_NONE=y
diff --git a/abs/core/kernel26/tmp/patch-2.6.37-ck2 b/abs/core/kernel26/tmp/patch-2.6.37-ck2
new file mode 100644
index 0000000..c4657e7
--- /dev/null
+++ b/abs/core/kernel26/tmp/patch-2.6.37-ck2
@@ -0,0 +1,9083 @@
+Index: linux-2.6.37-ck2/arch/powerpc/platforms/cell/spufs/sched.c
+===================================================================
+--- linux-2.6.37-ck2.orig/arch/powerpc/platforms/cell/spufs/sched.c 2010-05-17 18:51:19.000000000 +1000
++++ linux-2.6.37-ck2/arch/powerpc/platforms/cell/spufs/sched.c 2011-02-14 09:47:50.982252001 +1100
+@@ -64,11 +64,6 @@
+ static struct timer_list spuloadavg_timer;
+
+ /*
+- * Priority of a normal, non-rt, non-niced'd process (aka nice level 0).
+- */
+-#define NORMAL_PRIO 120
+-
+-/*
+ * Frequency of the spu scheduler tick. By default we do one SPU scheduler
+ * tick for every 10 CPU scheduler ticks.
+ */
+Index: linux-2.6.37-ck2/Documentation/scheduler/sched-BFS.txt
+===================================================================
+--- /dev/null 1970-01-01 00:00:00.000000000 +0000
++++ linux-2.6.37-ck2/Documentation/scheduler/sched-BFS.txt 2011-02-14 09:47:50.984252001 +1100
+@@ -0,0 +1,351 @@
++BFS - The Brain Fuck Scheduler by Con Kolivas.
++
++Goals.
++
++The goal of the Brain Fuck Scheduler, referred to as BFS from here on, is to
++completely do away with the complex designs of the past for the cpu process
++scheduler and instead implement one that is very simple in basic design.
++The main focus of BFS is to achieve excellent desktop interactivity and
++responsiveness without heuristics and tuning knobs that are difficult to
++understand, impossible to model and predict the effect of, and when tuned to
++one workload cause massive detriment to another.
++
++
++Design summary.
++
++BFS is best described as a single runqueue, O(n) lookup, earliest effective
++virtual deadline first design, loosely based on EEVDF (earliest eligible virtual
++deadline first) and my previous Staircase Deadline scheduler. Each component
++shall be described in order to understand the significance of, and reasoning for
++it. The codebase when the first stable version was released was approximately
++9000 lines less code than the existing mainline linux kernel scheduler (in
++2.6.31). This does not even take into account the removal of documentation and
++the cgroups code that is not used.
++
++Design reasoning.
++
++The single runqueue refers to the queued but not running processes for the
++entire system, regardless of the number of CPUs. The reason for going back to
++a single runqueue design is that once multiple runqueues are introduced,
++per-CPU or otherwise, there will be complex interactions as each runqueue will
++be responsible for the scheduling latency and fairness of the tasks only on its
++own runqueue, and to achieve fairness and low latency across multiple CPUs, any
++advantage in throughput of having CPU local tasks causes other disadvantages.
++This is due to requiring a very complex balancing system to at best achieve some
++semblance of fairness across CPUs and can only maintain relatively low latency
++for tasks bound to the same CPUs, not across them. To increase said fairness
++and latency across CPUs, the advantage of local runqueue locking, which makes
++for better scalability, is lost due to having to grab multiple locks.
++
++A significant feature of BFS is that all accounting is done purely based on CPU
++used and nowhere is sleep time used in any way to determine entitlement or
++interactivity. Interactivity "estimators" that use some kind of sleep/run
++algorithm are doomed to fail to detect all interactive tasks, and to falsely tag
++tasks that aren't interactive as being so. The reason for this is that it is
++close to impossible to determine that when a task is sleeping, whether it is
++doing it voluntarily, as in a userspace application waiting for input in the
++form of a mouse click or otherwise, or involuntarily, because it is waiting for
++another thread, process, I/O, kernel activity or whatever. Thus, such an
++estimator will introduce corner cases, and more heuristics will be required to
++cope with those corner cases, introducing more corner cases and failed
++interactivity detection and so on. Interactivity in BFS is built into the design
++by virtue of the fact that tasks that are waking up have not used up their quota
++of CPU time, and have earlier effective deadlines, thereby making it very likely
++they will preempt any CPU bound task of equivalent nice level. See below for
++more information on the virtual deadline mechanism. Even if they do not preempt
++a running task, because the rr interval is guaranteed to have a bound upper
++limit on how long a task will wait for, it will be scheduled within a timeframe
++that will not cause visible interface jitter.
++
++
++Design details.
++
++Task insertion.
++
++BFS inserts tasks into each relevant queue as an O(1) insertion into a double
++linked list. On insertion, *every* running queue is checked to see if the newly
++queued task can run on any idle queue, or preempt the lowest running task on the
++system. This is how the cross-CPU scheduling of BFS achieves significantly lower
++latency per extra CPU the system has. In this case the lookup is, in the worst
++case scenario, O(n) where n is the number of CPUs on the system.
++
++Data protection.
++
++BFS has one single lock protecting the process local data of every task in the
++global queue. Thus every insertion, removal and modification of task data in the
++global runqueue needs to grab the global lock. However, once a task is taken by
++a CPU, the CPU has its own local data copy of the running process' accounting
++information which only that CPU accesses and modifies (such as during a
++timer tick) thus allowing the accounting data to be updated lockless. Once a
++CPU has taken a task to run, it removes it from the global queue. Thus the
++global queue only ever has, at most,
++
++ (number of tasks requesting cpu time) - (number of logical CPUs) + 1
++
++tasks in the global queue. This value is relevant for the time taken to look up
++tasks during scheduling. This will increase if many tasks with CPU affinity set
++in their policy to limit which CPUs they're allowed to run on if they outnumber
++the number of CPUs. The +1 is because when rescheduling a task, the CPU's
++currently running task is put back on the queue. Lookup will be described after
++the virtual deadline mechanism is explained.
++
++Virtual deadline.
++
++The key to achieving low latency, scheduling fairness, and "nice level"
++distribution in BFS is entirely in the virtual deadline mechanism. The one
++tunable in BFS is the rr_interval, or "round robin interval". This is the
++maximum time two SCHED_OTHER (or SCHED_NORMAL, the common scheduling policy)
++tasks of the same nice level will be running for, or looking at it the other
++way around, the longest duration two tasks of the same nice level will be
++delayed for. When a task requests cpu time, it is given a quota (time_slice)
++equal to the rr_interval and a virtual deadline. The virtual deadline is
++offset from the current time in jiffies by this equation:
++
++ jiffies + (prio_ratio * rr_interval)
++
++The prio_ratio is determined as a ratio compared to the baseline of nice -20
++and increases by 10% per nice level. The deadline is a virtual one only in that
++no guarantee is placed that a task will actually be scheduled by this time, but
++it is used to compare which task should go next. There are three components to
++how a task is next chosen. First is time_slice expiration. If a task runs out
++of its time_slice, it is descheduled, the time_slice is refilled, and the
++deadline reset to that formula above. Second is sleep, where a task no longer
++is requesting CPU for whatever reason. The time_slice and deadline are _not_
++adjusted in this case and are just carried over for when the task is next
++scheduled. Third is preemption, and that is when a newly waking task is deemed
++higher priority than a currently running task on any cpu by virtue of the fact
++that it has an earlier virtual deadline than the currently running task. The
++earlier deadline is the key to which task is next chosen for the first and
++second cases. Once a task is descheduled, it is put back on the queue, and an
++O(n) lookup of all queued-but-not-running tasks is done to determine which has
++the earliest deadline and that task is chosen to receive CPU next.
++
++The CPU proportion of different nice tasks works out to be approximately the
++
++ (prio_ratio difference)^2
++
++The reason it is squared is that a task's deadline does not change while it is
++running unless it runs out of time_slice. Thus, even if the time actually
++passes the deadline of another task that is queued, it will not get CPU time
++unless the current running task deschedules, and the time "base" (jiffies) is
++constantly moving.
++
++Task lookup.
++
++BFS has 103 priority queues. 100 of these are dedicated to the static priority
++of realtime tasks, and the remaining 3 are, in order of best to worst priority,
++SCHED_ISO (isochronous), SCHED_NORMAL, and SCHED_IDLEPRIO (idle priority
++scheduling). When a task of these priorities is queued, a bitmap of running
++priorities is set showing which of these priorities has tasks waiting for CPU
++time. When a CPU is made to reschedule, the lookup for the next task to get
++CPU time is performed in the following way:
++
++First the bitmap is checked to see what static priority tasks are queued. If
++any realtime priorities are found, the corresponding queue is checked and the
++first task listed there is taken (provided CPU affinity is suitable) and lookup
++is complete. If the priority corresponds to a SCHED_ISO task, they are also
++taken in FIFO order (as they behave like SCHED_RR). If the priority corresponds
++to either SCHED_NORMAL or SCHED_IDLEPRIO, then the lookup becomes O(n). At this
++stage, every task in the runlist that corresponds to that priority is checked
++to see which has the earliest set deadline, and (provided it has suitable CPU
++affinity) it is taken off the runqueue and given the CPU. If a task has an
++expired deadline, it is taken and the rest of the lookup aborted (as they are
++chosen in FIFO order).
++
++Thus, the lookup is O(n) in the worst case only, where n is as described
++earlier, as tasks may be chosen before the whole task list is looked over.
++
++
++Scalability.
++
++The major limitations of BFS will be that of scalability, as the separate
++runqueue designs will have less lock contention as the number of CPUs rises.
++However they do not scale linearly even with separate runqueues as multiple
++runqueues will need to be locked concurrently on such designs to be able to
++achieve fair CPU balancing, to try and achieve some sort of nice-level fairness
++across CPUs, and to achieve low enough latency for tasks on a busy CPU when
++other CPUs would be more suited. BFS has the advantage that it requires no
++balancing algorithm whatsoever, as balancing occurs by proxy simply because
++all CPUs draw off the global runqueue, in priority and deadline order. Despite
++the fact that scalability is _not_ the prime concern of BFS, it both shows very
++good scalability to smaller numbers of CPUs and is likely a more scalable design
++at these numbers of CPUs.
++
++It also has some very low overhead scalability features built into the design
++when it has been deemed their overhead is so marginal that they're worth adding.
++The first is the local copy of the running process' data to the CPU it's running
++on to allow that data to be updated lockless where possible. Then there is
++deference paid to the last CPU a task was running on, by trying that CPU first
++when looking for an idle CPU to use the next time it's scheduled. Finally there
++is the notion of cache locality beyond the last running CPU. The sched_domains
++information is used to determine the relative virtual "cache distance" that
++other CPUs have from the last CPU a task was running on. CPUs with shared
++caches, such as SMT siblings, or multicore CPUs with shared caches, are treated
++as cache local. CPUs without shared caches are treated as not cache local, and
++CPUs on different NUMA nodes are treated as very distant. This "relative cache
++distance" is used by modifying the virtual deadline value when doing lookups.
++Effectively, the deadline is unaltered between "cache local" CPUs, doubled for
++"cache distant" CPUs, and quadrupled for "very distant" CPUs. The reasoning
++behind the doubling of deadlines is as follows. The real cost of migrating a
++task from one CPU to another is entirely dependant on the cache footprint of
++the task, how cache intensive the task is, how long it's been running on that
++CPU to take up the bulk of its cache, how big the CPU cache is, how fast and
++how layered the CPU cache is, how fast a context switch is... and so on. In
++other words, it's close to random in the real world where we do more than just
++one sole workload. The only thing we can be sure of is that it's not free. So
++BFS uses the principle that an idle CPU is a wasted CPU and utilising idle CPUs
++is more important than cache locality, and cache locality only plays a part
++after that. Doubling the effective deadline is based on the premise that the
++"cache local" CPUs will tend to work on the same tasks up to double the number
++of cache local CPUs, and once the workload is beyond that amount, it is likely
++that none of the tasks are cache warm anywhere anyway. The quadrupling for NUMA
++is a value I pulled out of my arse.
++
++When choosing an idle CPU for a waking task, the cache locality is determined
++according to where the task last ran and then idle CPUs are ranked from best
++to worst to choose the most suitable idle CPU based on cache locality, NUMA
++node locality and hyperthread sibling business. They are chosen in the
++following preference (if idle):
++
++* Same core, idle or busy cache, idle threads
++* Other core, same cache, idle or busy cache, idle threads.
++* Same node, other CPU, idle cache, idle threads.
++* Same node, other CPU, busy cache, idle threads.
++* Same core, busy threads.
++* Other core, same cache, busy threads.
++* Same node, other CPU, busy threads.
++* Other node, other CPU, idle cache, idle threads.
++* Other node, other CPU, busy cache, idle threads.
++* Other node, other CPU, busy threads.
++
++This shows the SMT or "hyperthread" awareness in the design as well which will
++choose a real idle core first before a logical SMT sibling which already has
++tasks on the physical CPU.
++
++Early benchmarking of BFS suggested scalability dropped off at the 16 CPU mark.
++However this benchmarking was performed on an earlier design that was far less
++scalable than the current one so it's hard to know how scalable it is in terms
++of both CPUs (due to the global runqueue) and heavily loaded machines (due to
++O(n) lookup) at this stage. Note that in terms of scalability, the number of
++_logical_ CPUs matters, not the number of _physical_ CPUs. Thus, a dual (2x)
++quad core (4X) hyperthreaded (2X) machine is effectively a 16X. Newer benchmark
++results are very promising indeed, without needing to tweak any knobs, features
++or options. Benchmark contributions are most welcome.
++
++
++Features
++
++As the initial prime target audience for BFS was the average desktop user, it
++was designed to not need tweaking, tuning or have features set to obtain benefit
++from it. Thus the number of knobs and features has been kept to an absolute
++minimum and should not require extra user input for the vast majority of cases.
++There are precisely 2 tunables, and 2 extra scheduling policies. The rr_interval
++and iso_cpu tunables, and the SCHED_ISO and SCHED_IDLEPRIO policies. In addition
++to this, BFS also uses sub-tick accounting. What BFS does _not_ now feature is
++support for CGROUPS. The average user should neither need to know what these
++are, nor should they need to be using them to have good desktop behaviour.
++
++rr_interval
++
++There is only one "scheduler" tunable, the round robin interval. This can be
++accessed in
++
++ /proc/sys/kernel/rr_interval
++
++The value is in milliseconds, and the default value is set to 6 on a
++uniprocessor machine, and automatically set to a progressively higher value on
++multiprocessor machines. The reasoning behind increasing the value on more CPUs
++is that the effective latency is decreased by virtue of there being more CPUs on
++BFS (for reasons explained above), and increasing the value allows for less
++cache contention and more throughput. Valid values are from 1 to 1000
++Decreasing the value will decrease latencies at the cost of decreasing
++throughput, while increasing it will improve throughput, but at the cost of
++worsening latencies. The accuracy of the rr interval is limited by HZ resolution
++of the kernel configuration. Thus, the worst case latencies are usually slightly
++higher than this actual value. The default value of 6 is not an arbitrary one.
++It is based on the fact that humans can detect jitter at approximately 7ms, so
++aiming for much lower latencies is pointless under most circumstances. It is
++worth noting this fact when comparing the latency performance of BFS to other
++schedulers. Worst case latencies being higher than 7ms are far worse than
++average latencies not being in the microsecond range.
++
++Isochronous scheduling.
++
++Isochronous scheduling is a unique scheduling policy designed to provide
++near-real-time performance to unprivileged (ie non-root) users without the
++ability to starve the machine indefinitely. Isochronous tasks (which means
++"same time") are set using, for example, the schedtool application like so:
++
++ schedtool -I -e amarok
++
++This will start the audio application "amarok" as SCHED_ISO. How SCHED_ISO works
++is that it has a priority level between true realtime tasks and SCHED_NORMAL
++which would allow them to preempt all normal tasks, in a SCHED_RR fashion (ie,
++if multiple SCHED_ISO tasks are running, they purely round robin at rr_interval
++rate). However if ISO tasks run for more than a tunable finite amount of time,
++they are then demoted back to SCHED_NORMAL scheduling. This finite amount of
++time is the percentage of _total CPU_ available across the machine, configurable
++as a percentage in the following "resource handling" tunable (as opposed to a
++scheduler tunable):
++
++ /proc/sys/kernel/iso_cpu
++
++and is set to 70% by default. It is calculated over a rolling 5 second average
++Because it is the total CPU available, it means that on a multi CPU machine, it
++is possible to have an ISO task running as realtime scheduling indefinitely on
++just one CPU, as the other CPUs will be available. Setting this to 100 is the
++equivalent of giving all users SCHED_RR access and setting it to 0 removes the
++ability to run any pseudo-realtime tasks.
++
++A feature of BFS is that it detects when an application tries to obtain a
++realtime policy (SCHED_RR or SCHED_FIFO) and the caller does not have the
++appropriate privileges to use those policies. When it detects this, it will
++give the task SCHED_ISO policy instead. Thus it is transparent to the user.
++Because some applications constantly set their policy as well as their nice
++level, there is potential for them to undo the override specified by the user
++on the command line of setting the policy to SCHED_ISO. To counter this, once
++a task has been set to SCHED_ISO policy, it needs superuser privileges to set
++it back to SCHED_NORMAL. This will ensure the task remains ISO and all child
++processes and threads will also inherit the ISO policy.
++
++Idleprio scheduling.
++
++Idleprio scheduling is a scheduling policy designed to give out CPU to a task
++_only_ when the CPU would be otherwise idle. The idea behind this is to allow
++ultra low priority tasks to be run in the background that have virtually no
++effect on the foreground tasks. This is ideally suited to distributed computing
++clients (like setiathome, folding, mprime etc) but can also be used to start
++a video encode or so on without any slowdown of other tasks. To avoid this
++policy from grabbing shared resources and holding them indefinitely, if it
++detects a state where the task is waiting on I/O, the machine is about to
++suspend to ram and so on, it will transiently schedule them as SCHED_NORMAL. As
++per the Isochronous task management, once a task has been scheduled as IDLEPRIO,
++it cannot be put back to SCHED_NORMAL without superuser privileges. Tasks can
++be set to start as SCHED_IDLEPRIO with the schedtool command like so:
++
++ schedtool -D -e ./mprime
++
++Subtick accounting.
++
++It is surprisingly difficult to get accurate CPU accounting, and in many cases,
++the accounting is done by simply determining what is happening at the precise
++moment a timer tick fires off. This becomes increasingly inaccurate as the
++timer tick frequency (HZ) is lowered. It is possible to create an application
++which uses almost 100% CPU, yet by being descheduled at the right time, records
++zero CPU usage. While the main problem with this is that there are possible
++security implications, it is also difficult to determine how much CPU a task
++really does use. BFS tries to use the sub-tick accounting from the TSC clock,
++where possible, to determine real CPU usage. This is not entirely reliable, but
++is far more likely to produce accurate CPU usage data than the existing designs
++and will not show tasks as consuming no CPU usage when they actually are. Thus,
++the amount of CPU reported as being used by BFS will more accurately represent
++how much CPU the task itself is using (as is shown for example by the 'time'
++application), so the reported values may be quite different to other schedulers.
++Values reported as the 'load' are more prone to problems with this design, but
++per process values are closer to real usage. When comparing throughput of BFS
++to other designs, it is important to compare the actual completed work in terms
++of total wall clock time taken and total work done, rather than the reported
++"cpu usage".
++
++
++Con Kolivas <kernel@kolivas.org> Fri Aug 27 2010
+Index: linux-2.6.37-ck2/Documentation/sysctl/kernel.txt
+===================================================================
+--- linux-2.6.37-ck2.orig/Documentation/sysctl/kernel.txt 2011-01-06 14:04:07.000000000 +1100
++++ linux-2.6.37-ck2/Documentation/sysctl/kernel.txt 2011-02-14 09:47:50.984252001 +1100
+@@ -32,6 +32,7 @@
+ - domainname
+ - hostname
+ - hotplug
++- iso_cpu
+ - java-appletviewer [ binfmt_java, obsolete ]
+ - java-interpreter [ binfmt_java, obsolete ]
+ - kstack_depth_to_print [ X86 only ]
+@@ -54,6 +55,7 @@
+ - randomize_va_space
+ - real-root-dev ==> Documentation/initrd.txt
+ - reboot-cmd [ SPARC only ]
++- rr_interval
+ - rtsig-max
+ - rtsig-nr
+ - sem
+@@ -254,6 +256,16 @@
+
+ ==============================================================
+
++iso_cpu: (BFS CPU scheduler only).
++
++This sets the percentage cpu that the unprivileged SCHED_ISO tasks can
++run effectively at realtime priority, averaged over a rolling five
++seconds over the -whole- system, meaning all cpus.
++
++Set to 70 (percent) by default.
++
++==============================================================
++
+ l2cr: (PPC only)
+
+ This flag controls the L2 cache of G3 processor boards. If
+@@ -428,6 +440,20 @@
+
+ ==============================================================
+
++rr_interval: (BFS CPU scheduler only)
++
++This is the smallest duration that any cpu process scheduling unit
++will run for. Increasing this value can increase throughput of cpu
++bound tasks substantially but at the expense of increased latencies
++overall. Conversely decreasing it will decrease average and maximum
++latencies but at the expense of throughput. This value is in
++milliseconds and the default value chosen depends on the number of
++cpus available at scheduler initialisation with a minimum of 6.
++
++Valid values are from 1-1000.
++
++==============================================================
++
+ rtsig-max & rtsig-nr:
+
+ The file rtsig-max can be used to tune the maximum number
+Index: linux-2.6.37-ck2/fs/proc/base.c
+===================================================================
+--- linux-2.6.37-ck2.orig/fs/proc/base.c 2011-01-06 14:04:10.000000000 +1100
++++ linux-2.6.37-ck2/fs/proc/base.c 2011-02-14 09:47:50.986252000 +1100
+@@ -356,7 +356,7 @@
+ static int proc_pid_schedstat(struct task_struct *task, char *buffer)
+ {
+ return sprintf(buffer, "%llu %llu %lu\n",
+- (unsigned long long)task->se.sum_exec_runtime,
++ (unsigned long long)tsk_seruntime(task),
+ (unsigned long long)task->sched_info.run_delay,
+ task->sched_info.pcount);
+ }
+Index: linux-2.6.37-ck2/include/linux/init_task.h
+===================================================================
+--- linux-2.6.37-ck2.orig/include/linux/init_task.h 2011-01-06 14:04:10.000000000 +1100
++++ linux-2.6.37-ck2/include/linux/init_task.h 2011-02-14 09:47:50.986252001 +1100
+@@ -114,6 +114,67 @@
+ * INIT_TASK is used to set up the first task table, touch at
+ * your own risk!. Base=0, limit=0x1fffff (=2MB)
+ */
++#ifdef CONFIG_SCHED_BFS
++#define INIT_TASK(tsk) \
++{ \
++ .state = 0, \
++ .stack = &init_thread_info, \
++ .usage = ATOMIC_INIT(2), \
++ .flags = PF_KTHREAD, \
++ .lock_depth = -1, \
++ .prio = NORMAL_PRIO, \
++ .static_prio = MAX_PRIO-20, \
++ .normal_prio = NORMAL_PRIO, \
++ .deadline = 0, \
++ .policy = SCHED_NORMAL, \
++ .cpus_allowed = CPU_MASK_ALL, \
++ .mm = NULL, \
++ .active_mm = &init_mm, \
++ .run_list = LIST_HEAD_INIT(tsk.run_list), \
++ .time_slice = HZ, \
++ .tasks = LIST_HEAD_INIT(tsk.tasks), \
++ .pushable_tasks = PLIST_NODE_INIT(tsk.pushable_tasks, MAX_PRIO), \
++ .ptraced = LIST_HEAD_INIT(tsk.ptraced), \
++ .ptrace_entry = LIST_HEAD_INIT(tsk.ptrace_entry), \
++ .real_parent = &tsk, \
++ .parent = &tsk, \
++ .children = LIST_HEAD_INIT(tsk.children), \
++ .sibling = LIST_HEAD_INIT(tsk.sibling), \
++ .group_leader = &tsk, \
++ RCU_INIT_POINTER(.real_cred, &init_cred), \
++ RCU_INIT_POINTER(.cred, &init_cred), \
++ .comm = "swapper", \
++ .thread = INIT_THREAD, \
++ .fs = &init_fs, \
++ .files = &init_files, \
++ .signal = &init_signals, \
++ .sighand = &init_sighand, \
++ .nsproxy = &init_nsproxy, \
++ .pending = { \
++ .list = LIST_HEAD_INIT(tsk.pending.list), \
++ .signal = {{0}}}, \
++ .blocked = {{0}}, \
++ .alloc_lock = __SPIN_LOCK_UNLOCKED(tsk.alloc_lock), \
++ .journal_info = NULL, \
++ .cpu_timers = INIT_CPU_TIMERS(tsk.cpu_timers), \
++ .fs_excl = ATOMIC_INIT(0), \
++ .pi_lock = __RAW_SPIN_LOCK_UNLOCKED(tsk.pi_lock), \
++ .timer_slack_ns = 50000, /* 50 usec default slack */ \
++ .pids = { \
++ [PIDTYPE_PID] = INIT_PID_LINK(PIDTYPE_PID), \
++ [PIDTYPE_PGID] = INIT_PID_LINK(PIDTYPE_PGID), \
++ [PIDTYPE_SID] = INIT_PID_LINK(PIDTYPE_SID), \
++ }, \
++ .dirties = INIT_PROP_LOCAL_SINGLE(dirties), \
++ INIT_IDS \
++ INIT_PERF_EVENTS(tsk) \
++ INIT_TRACE_IRQFLAGS \
++ INIT_LOCKDEP \
++ INIT_FTRACE_GRAPH \
++ INIT_TRACE_RECURSION \
++ INIT_TASK_RCU_PREEMPT(tsk) \
++}
++#else /* CONFIG_SCHED_BFS */
+ #define INIT_TASK(tsk) \
+ { \
+ .state = 0, \
+@@ -179,7 +240,7 @@
+ INIT_TRACE_RECURSION \
+ INIT_TASK_RCU_PREEMPT(tsk) \
+ }
+-
++#endif /* CONFIG_SCHED_BFS */
+
+ #define INIT_CPU_TIMERS(cpu_timers) \
+ { \
+Index: linux-2.6.37-ck2/include/linux/ioprio.h
+===================================================================
+--- linux-2.6.37-ck2.orig/include/linux/ioprio.h 2009-06-10 13:05:27.000000000 +1000
++++ linux-2.6.37-ck2/include/linux/ioprio.h 2011-02-14 09:47:50.986252001 +1100
+@@ -64,6 +64,8 @@
+
+ static inline int task_nice_ioprio(struct task_struct *task)
+ {
++ if (iso_task(task))
++ return 0;
+ return (task_nice(task) + 20) / 5;
+ }
+
+Index: linux-2.6.37-ck2/include/linux/sched.h
+===================================================================
+--- linux-2.6.37-ck2.orig/include/linux/sched.h 2011-01-06 14:04:10.000000000 +1100
++++ linux-2.6.37-ck2/include/linux/sched.h 2011-02-14 10:11:01.691252000 +1100
+@@ -36,8 +36,15 @@
+ #define SCHED_FIFO 1
+ #define SCHED_RR 2
+ #define SCHED_BATCH 3
+-/* SCHED_ISO: reserved but not implemented yet */
++/* SCHED_ISO: Implemented on BFS only */
+ #define SCHED_IDLE 5
++#define SCHED_IDLEPRIO SCHED_IDLE
++#ifdef CONFIG_SCHED_BFS
++#define SCHED_ISO 4
++#define SCHED_MAX (SCHED_IDLEPRIO)
++#define SCHED_RANGE(policy) ((policy) <= SCHED_MAX)
++#endif
++
+ /* Can be ORed in to make sure the process is reverted back to SCHED_NORMAL on fork */
+ #define SCHED_RESET_ON_FORK 0x40000000
+
+@@ -268,8 +275,6 @@
+ extern void init_idle(struct task_struct *idle, int cpu);
+ extern void init_idle_bootup_task(struct task_struct *idle);
+
+-extern int runqueue_is_locked(int cpu);
+-
+ extern cpumask_var_t nohz_cpu_mask;
+ #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ)
+ extern void select_nohz_load_balancer(int stop_tick);
+@@ -1188,17 +1193,31 @@
+
+ int lock_depth; /* BKL lock depth */
+
++#ifndef CONFIG_SCHED_BFS
+ #ifdef CONFIG_SMP
+ #ifdef __ARCH_WANT_UNLOCKED_CTXSW
+ int oncpu;
+ #endif
+ #endif
++#else /* CONFIG_SCHED_BFS */
++ int oncpu;
++#endif
+
+ int prio, static_prio, normal_prio;
+ unsigned int rt_priority;
++#ifdef CONFIG_SCHED_BFS
++ int time_slice;
++ u64 deadline;
++ struct list_head run_list;
++ u64 last_ran;
++ u64 sched_time; /* sched_clock time spent running */
++
++ unsigned long rt_timeout;
++#else /* CONFIG_SCHED_BFS */
+ const struct sched_class *sched_class;
+ struct sched_entity se;
+ struct sched_rt_entity rt;
++#endif
+
+ #ifdef CONFIG_PREEMPT_NOTIFIERS
+ /* list of struct preempt_notifier: */
+@@ -1295,6 +1314,9 @@
+ int __user *clear_child_tid; /* CLONE_CHILD_CLEARTID */
+
+ cputime_t utime, stime, utimescaled, stimescaled;
++#ifdef CONFIG_SCHED_BFS
++ unsigned long utime_pc, stime_pc;
++#endif
+ cputime_t gtime;
+ #ifndef CONFIG_VIRT_CPU_ACCOUNTING
+ cputime_t prev_utime, prev_stime;
+@@ -1514,6 +1536,60 @@
+ #endif
+ };
+
++#ifdef CONFIG_SCHED_BFS
++extern int grunqueue_is_locked(void);
++extern void grq_unlock_wait(void);
++#define tsk_seruntime(t) ((t)->sched_time)
++#define tsk_rttimeout(t) ((t)->rt_timeout)
++
++static inline void tsk_cpus_current(struct task_struct *p)
++{
++}
++
++#define runqueue_is_locked(cpu) grunqueue_is_locked()
++
++static inline void print_scheduler_version(void)
++{
++ printk(KERN_INFO"BFS CPU scheduler v0.363 by Con Kolivas.\n");
++}
++
++static inline int iso_task(struct task_struct *p)
++{
++ return (p->policy == SCHED_ISO);
++}
++extern void remove_cpu(unsigned long cpu);
++extern int above_background_load(void);
++#else /* CFS */
++extern int runqueue_is_locked(int cpu);
++#define tsk_seruntime(t) ((t)->se.sum_exec_runtime)
++#define tsk_rttimeout(t) ((t)->rt.timeout)
++
++static inline void tsk_cpus_current(struct task_struct *p)
++{
++ p->rt.nr_cpus_allowed = current->rt.nr_cpus_allowed;
++}
++
++static inline void print_scheduler_version(void)
++{
++ printk(KERN_INFO"CFS CPU scheduler.\n");
++}
++
++static inline int iso_task(struct task_struct *p)
++{
++ return 0;
++}
++
++static inline void remove_cpu(unsigned long cpu)
++{
++}
++
++/* Anyone feel like implementing this? */
++static inline int above_background_load(void)
++{
++ return 1;
++}
++#endif /* CONFIG_SCHED_BFS */
++
+ /* Future-safe accessor for struct task_struct's cpus_allowed. */
+ #define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed)
+
+@@ -1531,10 +1607,20 @@
+ */
+
+ #define MAX_USER_RT_PRIO 100
+-#define MAX_RT_PRIO MAX_USER_RT_PRIO
++#define MAX_RT_PRIO (MAX_USER_RT_PRIO + 1)
++#define DEFAULT_PRIO (MAX_RT_PRIO + 20)
+
++#ifdef CONFIG_SCHED_BFS
++#define PRIO_RANGE (40)
++#define MAX_PRIO (MAX_RT_PRIO + PRIO_RANGE)
++#define ISO_PRIO (MAX_RT_PRIO)
++#define NORMAL_PRIO (MAX_RT_PRIO + 1)
++#define IDLE_PRIO (MAX_RT_PRIO + 2)
++#define PRIO_LIMIT ((IDLE_PRIO) + 1)
++#else /* CONFIG_SCHED_BFS */
+ #define MAX_PRIO (MAX_RT_PRIO + 40)
+-#define DEFAULT_PRIO (MAX_RT_PRIO + 20)
++#define NORMAL_PRIO DEFAULT_PRIO
++#endif /* CONFIG_SCHED_BFS */
+
+ static inline int rt_prio(int prio)
+ {
+@@ -1862,7 +1948,7 @@
+ extern unsigned long long thread_group_sched_runtime(struct task_struct *task);
+
+ /* sched_exec is called by processes performing an exec */
+-#ifdef CONFIG_SMP
++#if defined(CONFIG_SMP) && !defined(CONFIG_SCHED_BFS)
+ extern void sched_exec(void);
+ #else
+ #define sched_exec() {}
+Index: linux-2.6.37-ck2/init/Kconfig
+===================================================================
+--- linux-2.6.37-ck2.orig/init/Kconfig 2011-01-06 14:04:10.000000000 +1100
++++ linux-2.6.37-ck2/init/Kconfig 2011-02-14 09:47:50.988252001 +1100
+@@ -30,6 +30,19 @@
+
+ menu "General setup"
+
++config SCHED_BFS
++ bool "BFS cpu scheduler"
++ ---help---
++ The Brain Fuck CPU Scheduler for excellent interactivity and
++ responsiveness on the desktop and solid scalability on normal
++ hardware. Not recommended for 4096 CPUs.
++
++ Currently incompatible with the Group CPU scheduler, and RCU TORTURE
++ TEST so these options are disabled.
++
++ Say Y here.
++ default y
++
+ config EXPERIMENTAL
+ bool "Prompt for development and/or incomplete code/drivers"
+ ---help---
+@@ -563,6 +576,7 @@
+
+ config CGROUP_CPUACCT
+ bool "Simple CPU accounting cgroup subsystem"
++ depends on !SCHED_BFS
+ help
+ Provides a simple Resource Controller for monitoring the
+ total CPU consumed by the tasks in a cgroup.
+@@ -629,7 +643,7 @@
+
+ menuconfig CGROUP_SCHED
+ bool "Group CPU scheduler"
+- depends on EXPERIMENTAL
++ depends on EXPERIMENTAL && !SCHED_BFS
+ default n
+ help
+ This feature lets CPU scheduler recognize task groups and control CPU
+Index: linux-2.6.37-ck2/init/main.c
+===================================================================
+--- linux-2.6.37-ck2.orig/init/main.c 2011-01-06 14:04:10.000000000 +1100
++++ linux-2.6.37-ck2/init/main.c 2011-02-14 09:47:50.989252001 +1100
+@@ -824,6 +824,7 @@
+ system_state = SYSTEM_RUNNING;
+ numa_default_policy();
+
++ print_scheduler_version();
+
+ current->signal->flags |= SIGNAL_UNKILLABLE;
+
+Index: linux-2.6.37-ck2/kernel/delayacct.c
+===================================================================
+--- linux-2.6.37-ck2.orig/kernel/delayacct.c 2009-12-03 21:40:09.000000000 +1100
++++ linux-2.6.37-ck2/kernel/delayacct.c 2011-02-14 09:47:50.989252001 +1100
+@@ -128,7 +128,7 @@
+ */
+ t1 = tsk->sched_info.pcount;
+ t2 = tsk->sched_info.run_delay;
+- t3 = tsk->se.sum_exec_runtime;
++ t3 = tsk_seruntime(tsk);
+
+ d->cpu_count += t1;
+
+Index: linux-2.6.37-ck2/kernel/exit.c
+===================================================================
+--- linux-2.6.37-ck2.orig/kernel/exit.c 2011-01-06 14:04:10.000000000 +1100
++++ linux-2.6.37-ck2/kernel/exit.c 2011-02-14 09:47:50.989252001 +1100
+@@ -132,7 +132,7 @@
+ sig->inblock += task_io_get_inblock(tsk);
+ sig->oublock += task_io_get_oublock(tsk);
+ task_io_accounting_add(&sig->ioac, &tsk->ioac);
+- sig->sum_sched_runtime += tsk->se.sum_exec_runtime;
++ sig->sum_sched_runtime += tsk_seruntime(tsk);
+ }
+
+ sig->nr_threads--;
+Index: linux-2.6.37-ck2/kernel/kthread.c
+===================================================================
+--- linux-2.6.37-ck2.orig/kernel/kthread.c 2011-01-06 14:04:10.000000000 +1100
++++ linux-2.6.37-ck2/kernel/kthread.c 2011-02-14 09:47:50.989252001 +1100
+@@ -184,7 +184,9 @@
+ }
+
+ p->cpus_allowed = cpumask_of_cpu(cpu);
++#ifndef CONFIG_SCHED_BFS
+ p->rt.nr_cpus_allowed = 1;
++#endif
+ p->flags |= PF_THREAD_BOUND;
+ }
+ EXPORT_SYMBOL(kthread_bind);
+Index: linux-2.6.37-ck2/kernel/posix-cpu-timers.c
+===================================================================
+--- linux-2.6.37-ck2.orig/kernel/posix-cpu-timers.c 2011-01-06 14:04:10.000000000 +1100
++++ linux-2.6.37-ck2/kernel/posix-cpu-timers.c 2011-02-14 09:47:50.990252001 +1100
+@@ -248,7 +248,7 @@
+ do {
+ times->utime = cputime_add(times->utime, t->utime);
+ times->stime = cputime_add(times->stime, t->stime);
+- times->sum_exec_runtime += t->se.sum_exec_runtime;
++ times->sum_exec_runtime += tsk_seruntime(t);
+ } while_each_thread(tsk, t);
+ out:
+ rcu_read_unlock();
+@@ -508,7 +508,7 @@
+ void posix_cpu_timers_exit(struct task_struct *tsk)
+ {
+ cleanup_timers(tsk->cpu_timers,
+- tsk->utime, tsk->stime, tsk->se.sum_exec_runtime);
++ tsk->utime, tsk->stime, tsk_seruntime(tsk));
+
+ }
+ void posix_cpu_timers_exit_group(struct task_struct *tsk)
+@@ -518,7 +518,7 @@
+ cleanup_timers(tsk->signal->cpu_timers,
+ cputime_add(tsk->utime, sig->utime),
+ cputime_add(tsk->stime, sig->stime),
+- tsk->se.sum_exec_runtime + sig->sum_sched_runtime);
++ tsk_seruntime(tsk) + sig->sum_sched_runtime);
+ }
+
+ static void clear_dead_task(struct k_itimer *timer, union cpu_time_count now)
+@@ -949,7 +949,7 @@
+ struct cpu_timer_list *t = list_first_entry(timers,
+ struct cpu_timer_list,
+ entry);
+- if (!--maxfire || tsk->se.sum_exec_runtime < t->expires.sched) {
++ if (!--maxfire || tsk_seruntime(tsk) < t->expires.sched) {
+ tsk->cputime_expires.sched_exp = t->expires.sched;
+ break;
+ }
+@@ -966,7 +966,7 @@
+ ACCESS_ONCE(sig->rlim[RLIMIT_RTTIME].rlim_max);
+
+ if (hard != RLIM_INFINITY &&
+- tsk->rt.timeout > DIV_ROUND_UP(hard, USEC_PER_SEC/HZ)) {
++ tsk_rttimeout(tsk) > DIV_ROUND_UP(hard, USEC_PER_SEC/HZ)) {
+ /*
+ * At the hard limit, we just die.
+ * No need to calculate anything else now.
+@@ -974,7 +974,7 @@
+ __group_send_sig_info(SIGKILL, SEND_SIG_PRIV, tsk);
+ return;
+ }
+- if (tsk->rt.timeout > DIV_ROUND_UP(soft, USEC_PER_SEC/HZ)) {
++ if (tsk_rttimeout(tsk) > DIV_ROUND_UP(soft, USEC_PER_SEC/HZ)) {
+ /*
+ * At the soft limit, send a SIGXCPU every second.
+ */
+@@ -1276,7 +1276,7 @@
+ struct task_cputime task_sample = {
+ .utime = tsk->utime,
+ .stime = tsk->stime,
+- .sum_exec_runtime = tsk->se.sum_exec_runtime
++ .sum_exec_runtime = tsk_seruntime(tsk)
+ };
+
+ if (task_cputime_expired(&task_sample, &tsk->cputime_expires))
+Index: linux-2.6.37-ck2/kernel/sched_bfs.c
+===================================================================
+--- /dev/null 1970-01-01 00:00:00.000000000 +0000
++++ linux-2.6.37-ck2/kernel/sched_bfs.c 2011-02-14 10:11:00.294252001 +1100
+@@ -0,0 +1,7243 @@
++/*
++ * kernel/sched_bfs.c, was sched.c
++ *
++ * Kernel scheduler and related syscalls
++ *
++ * Copyright (C) 1991-2002 Linus Torvalds
++ *
++ * 1996-12-23 Modified by Dave Grothe to fix bugs in semaphores and
++ * make semaphores SMP safe
++ * 1998-11-19 Implemented schedule_timeout() and related stuff
++ * by Andrea Arcangeli
++ * 2002-01-04 New ultra-scalable O(1) scheduler by Ingo Molnar:
++ * hybrid priority-list and round-robin design with
++ * an array-switch method of distributing timeslices
++ * and per-CPU runqueues. Cleanups and useful suggestions
++ * by Davide Libenzi, preemptible kernel bits by Robert Love.
++ * 2003-09-03 Interactivity tuning by Con Kolivas.
++ * 2004-04-02 Scheduler domains code by Nick Piggin
++ * 2007-04-15 Work begun on replacing all interactivity tuning with a
++ * fair scheduling design by Con Kolivas.
++ * 2007-05-05 Load balancing (smp-nice) and other improvements
++ * by Peter Williams
++ * 2007-05-06 Interactivity improvements to CFS by Mike Galbraith
++ * 2007-07-01 Group scheduling enhancements by Srivatsa Vaddagiri
++ * 2007-11-29 RT balancing improvements by Steven Rostedt, Gregory Haskins,
++ * Thomas Gleixner, Mike Kravetz
++ * now Brainfuck deadline scheduling policy by Con Kolivas deletes
++ * a whole lot of those previous things.
++ */
++
++#include <linux/mm.h>
++#include <linux/module.h>
++#include <linux/nmi.h>
++#include <linux/init.h>
++#include <asm/uaccess.h>
++#include <linux/highmem.h>
++#include <linux/smp_lock.h>
++#include <asm/mmu_context.h>
++#include <linux/interrupt.h>
++#include <linux/capability.h>
++#include <linux/completion.h>
++#include <linux/kernel_stat.h>
++#include <linux/debug_locks.h>
++#include <linux/perf_event.h>
++#include <linux/security.h>
++#include <linux/notifier.h>
++#include <linux/profile.h>
++#include <linux/freezer.h>
++#include <linux/vmalloc.h>
++#include <linux/blkdev.h>
++#include <linux/delay.h>
++#include <linux/smp.h>
++#include <linux/threads.h>
++#include <linux/timer.h>
++#include <linux/rcupdate.h>
++#include <linux/cpu.h>
++#include <linux/cpuset.h>
++#include <linux/cpumask.h>
++#include <linux/percpu.h>
++#include <linux/proc_fs.h>
++#include <linux/seq_file.h>
++#include <linux/syscalls.h>
++#include <linux/times.h>
++#include <linux/tsacct_kern.h>
++#include <linux/kprobes.h>
++#include <linux/delayacct.h>
++#include <linux/log2.h>
++#include <linux/bootmem.h>
++#include <linux/ftrace.h>
++#include <linux/slab.h>
++
++#include <asm/tlb.h>
++#include <asm/unistd.h>
++
++#include "sched_cpupri.h"
++#include "workqueue_sched.h"
++
++#define CREATE_TRACE_POINTS
++#include <trace/events/sched.h>
++
++#define rt_prio(prio) unlikely((prio) < MAX_RT_PRIO)
++#define rt_task(p) rt_prio((p)->prio)
++#define rt_queue(rq) rt_prio((rq)->rq_prio)
++#define batch_task(p) (unlikely((p)->policy == SCHED_BATCH))
++#define is_rt_policy(policy) ((policy) == SCHED_FIFO || \
++ (policy) == SCHED_RR)
++#define has_rt_policy(p) unlikely(is_rt_policy((p)->policy))
++#define idleprio_task(p) unlikely((p)->policy == SCHED_IDLEPRIO)
++#define iso_task(p) unlikely((p)->policy == SCHED_ISO)
++#define iso_queue(rq) unlikely((rq)->rq_policy == SCHED_ISO)
++#define ISO_PERIOD ((5 * HZ * num_online_cpus()) + 1)
++
++/*
++ * Convert user-nice values [ -20 ... 0 ... 19 ]
++ * to static priority [ MAX_RT_PRIO..MAX_PRIO-1 ],
++ * and back.
++ */
++#define NICE_TO_PRIO(nice) (MAX_RT_PRIO + (nice) + 20)
++#define PRIO_TO_NICE(prio) ((prio) - MAX_RT_PRIO - 20)
++#define TASK_NICE(p) PRIO_TO_NICE((p)->static_prio)
++
++/*
++ * 'User priority' is the nice value converted to something we
++ * can work with better when scaling various scheduler parameters,
++ * it's a [ 0 ... 39 ] range.
++ */
++#define USER_PRIO(p) ((p) - MAX_RT_PRIO)
++#define TASK_USER_PRIO(p) USER_PRIO((p)->static_prio)
++#define MAX_USER_PRIO (USER_PRIO(MAX_PRIO))
++#define SCHED_PRIO(p) ((p) + MAX_RT_PRIO)
++#define STOP_PRIO (MAX_RT_PRIO - 1)
++
++/*
++ * Some helpers for converting to/from various scales. Use shifts to get
++ * approximate multiples of ten for less overhead.
++ */
++#define JIFFIES_TO_NS(TIME) ((TIME) * (1000000000 / HZ))
++#define JIFFY_NS (1000000000 / HZ)
++#define HALF_JIFFY_NS (1000000000 / HZ / 2)
++#define HALF_JIFFY_US (1000000 / HZ / 2)
++#define MS_TO_NS(TIME) ((TIME) << 20)
++#define MS_TO_US(TIME) ((TIME) << 10)
++#define NS_TO_MS(TIME) ((TIME) >> 20)
++#define NS_TO_US(TIME) ((TIME) >> 10)
++
++#define RESCHED_US (100) /* Reschedule if less than this many μs left */
++
++/*
++ * This is the time all tasks within the same priority round robin.
++ * Value is in ms and set to a minimum of 6ms. Scales with number of cpus.
++ * Tunable via /proc interface.
++ */
++int rr_interval __read_mostly = 6;
++
++/*
++ * sched_iso_cpu - sysctl which determines the cpu percentage SCHED_ISO tasks
++ * are allowed to run five seconds as real time tasks. This is the total over
++ * all online cpus.
++ */
++int sched_iso_cpu __read_mostly = 70;
++
++/*
++ * The relative length of deadline for each priority(nice) level.
++ */
++static int prio_ratios[PRIO_RANGE] __read_mostly;
++
++/*
++ * The quota handed out to tasks of all priority levels when refilling their
++ * time_slice.
++ */
++static inline unsigned long timeslice(void)
++{
++ return MS_TO_US(rr_interval);
++}
++
++/*
++ * The global runqueue data that all CPUs work off. Data is protected either
++ * by the global grq lock, or the discrete lock that precedes the data in this
++ * struct.
++ */
++struct global_rq {
++ raw_spinlock_t lock;
++ unsigned long nr_running;
++ unsigned long nr_uninterruptible;
++ unsigned long long nr_switches;
++ struct list_head queue[PRIO_LIMIT];
++ DECLARE_BITMAP(prio_bitmap, PRIO_LIMIT + 1);
++#ifdef CONFIG_SMP
++ unsigned long qnr; /* queued not running */
++ cpumask_t cpu_idle_map;
++ int idle_cpus;
++#endif
++ u64 niffies; /* Nanosecond jiffies */
++ unsigned long last_jiffy; /* Last jiffy we updated niffies */
++
++ raw_spinlock_t iso_lock;
++ int iso_ticks;
++ int iso_refractory;
++};
++
++/* There can be only one */
++static struct global_rq grq;
++
++/*
++ * This is the main, per-CPU runqueue data structure.
++ * This data should only be modified by the local cpu.
++ */
++struct rq {
++#ifdef CONFIG_SMP
++#ifdef CONFIG_NO_HZ
++ u64 nohz_stamp;
++ unsigned char in_nohz_recently;
++#endif
++#endif
++
++ struct task_struct *curr, *idle, *stop;
++ struct mm_struct *prev_mm;
++
++ /* Stored data about rq->curr to work outside grq lock */
++ u64 rq_deadline;
++ unsigned int rq_policy;
++ int rq_time_slice;
++ u64 rq_last_ran;
++ int rq_prio;
++ int rq_running; /* There is a task running */
++
++ /* Accurate timekeeping data */
++ u64 timekeep_clock;
++ unsigned long user_pc, nice_pc, irq_pc, softirq_pc, system_pc,
++ iowait_pc, idle_pc;
++ atomic_t nr_iowait;
++
++#ifdef CONFIG_SMP
++ int cpu; /* cpu of this runqueue */
++ int online;
++
++ struct root_domain *rd;
++ struct sched_domain *sd;
++ unsigned long *cpu_locality; /* CPU relative cache distance */
++#ifdef CONFIG_SCHED_SMT
++ int (*siblings_idle)(unsigned long cpu);
++ /* See if all smt siblings are idle */
++ cpumask_t smt_siblings;
++#endif
++#ifdef CONFIG_SCHED_MC
++ int (*cache_idle)(unsigned long cpu);
++ /* See if all cache siblings are idle */
++ cpumask_t cache_siblings;
++#endif
++ u64 last_niffy; /* Last time this RQ updated grq.niffies */
++#endif
++#ifdef CONFIG_IRQ_TIME_ACCOUNTING
++ u64 prev_irq_time;
++#endif
++ u64 clock, old_clock, last_tick;
++ u64 clock_task;
++ int dither;
++
++#ifdef CONFIG_SCHEDSTATS
++
++ /* latency stats */
++ struct sched_info rq_sched_info;
++ unsigned long long rq_cpu_time;
++ /* could above be rq->cfs_rq.exec_clock + rq->rt_rq.rt_runtime ? */
++
++ /* sys_sched_yield() stats */
++ unsigned int yld_count;
++
++ /* schedule() stats */
++ unsigned int sched_switch;
++ unsigned int sched_count;
++ unsigned int sched_goidle;
++
++ /* try_to_wake_up() stats */
++ unsigned int ttwu_count;
++ unsigned int ttwu_local;
++
++ /* BKL stats */
++ unsigned int bkl_count;
++#endif
++};
++
++static DEFINE_PER_CPU(struct rq, runqueues) ____cacheline_aligned_in_smp;
++static DEFINE_MUTEX(sched_hotcpu_mutex);
++
++#ifdef CONFIG_SMP
++/*
++ * sched_domains_mutex serializes calls to arch_init_sched_domains,
++ * detach_destroy_domains and partition_sched_domains.
++ */
++static DEFINE_MUTEX(sched_domains_mutex);
++
++/*
++ * By default the system creates a single root-domain with all cpus as
++ * members (mimicking the global state we have today).
++ */
++static struct root_domain def_root_domain;
++
++int __weak arch_sd_sibling_asym_packing(void)
++{
++ return 0*SD_ASYM_PACKING;
++}
++#endif
++
++/*
++ * We add the notion of a root-domain which will be used to define per-domain
++ * variables. Each exclusive cpuset essentially defines an island domain by
++ * fully partitioning the member cpus from any other cpuset. Whenever a new
++ * exclusive cpuset is created, we also create and attach a new root-domain
++ * object.
++ *
++ */
++struct root_domain {
++ atomic_t refcount;
++ cpumask_var_t span;
++ cpumask_var_t online;
++
++ /*
++ * The "RT overload" flag: it gets set if a CPU has more than
++ * one runnable RT task.
++ */
++ cpumask_var_t rto_mask;
++ atomic_t rto_count;
++#ifdef CONFIG_SMP
++ struct cpupri cpupri;
++#endif
++};
++
++#define rcu_dereference_check_sched_domain(p) \
++ rcu_dereference_check((p), \
++ rcu_read_lock_sched_held() || \
++ lockdep_is_held(&sched_domains_mutex))
++
++/*
++ * The domain tree (rq->sd) is protected by RCU's quiescent state transition.
++ * See detach_destroy_domains: synchronize_sched for details.
++ *
++ * The domain tree of any CPU may only be accessed from within
++ * preempt-disabled sections.
++ */
++#define for_each_domain(cpu, __sd) \
++ for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); __sd; __sd = __sd->parent)
++
++static inline void update_rq_clock(struct rq *rq);
++
++/*
++ * Sanity check should sched_clock return bogus values. We make sure it does
++ * not appear to go backwards, and use jiffies to determine the maximum and
++ * minimum it could possibly have increased, and round down to the nearest
++ * jiffy when it falls outside this.
++ */
++static inline void niffy_diff(s64 *niff_diff, int jiff_diff)
++{
++ unsigned long min_diff, max_diff;
++
++ if (jiff_diff > 1)
++ min_diff = JIFFIES_TO_NS(jiff_diff - 1);
++ else
++ min_diff = 1;
++ /* Round up to the nearest tick for maximum */
++ max_diff = JIFFIES_TO_NS(jiff_diff + 1);
++
++ if (unlikely(*niff_diff < min_diff || *niff_diff > max_diff))
++ *niff_diff = min_diff;
++}
++
++#ifdef CONFIG_SMP
++#define cpu_rq(cpu) (&per_cpu(runqueues, (cpu)))
++#define this_rq() (&__get_cpu_var(runqueues))
++#define task_rq(p) cpu_rq(task_cpu(p))
++#define cpu_curr(cpu) (cpu_rq(cpu)->curr)
++static inline int cpu_of(struct rq *rq)
++{
++ return rq->cpu;
++}
++
++/*
++ * Niffies are a globally increasing nanosecond counter. Whenever a runqueue
++ * clock is updated with the grq.lock held, it is an opportunity to update the
++ * niffies value. Any CPU can update it by adding how much its clock has
++ * increased since it last updated niffies, minus any added niffies by other
++ * CPUs.
++ */
++static inline void update_clocks(struct rq *rq)
++{
++ s64 ndiff;
++ long jdiff;
++
++ update_rq_clock(rq);
++ ndiff = rq->clock - rq->old_clock;
++ /* old_clock is only updated when we are updating niffies */
++ rq->old_clock = rq->clock;
++ ndiff -= grq.niffies - rq->last_niffy;
++ jdiff = jiffies - grq.last_jiffy;
++ niffy_diff(&ndiff, jdiff);
++ grq.last_jiffy += jdiff;
++ grq.niffies += ndiff;
++ rq->last_niffy = grq.niffies;
++}
++#else /* CONFIG_SMP */
++static struct rq *uprq;
++#define cpu_rq(cpu) (uprq)
++#define this_rq() (uprq)
++#define task_rq(p) (uprq)
++#define cpu_curr(cpu) ((uprq)->curr)
++static inline int cpu_of(struct rq *rq)
++{
++ return 0;
++}
++
++static inline void update_clocks(struct rq *rq)
++{
++ s64 ndiff;
++ long jdiff;
++
++ update_rq_clock(rq);
++ ndiff = rq->clock - rq->old_clock;
++ rq->old_clock = rq->clock;
++ jdiff = jiffies - grq.last_jiffy;
++ niffy_diff(&ndiff, jdiff);
++ grq.last_jiffy += jdiff;
++ grq.niffies += ndiff;
++}
++#endif
++#define raw_rq() (&__raw_get_cpu_var(runqueues))
++
++#include "sched_stats.h"
++
++#ifndef prepare_arch_switch
++# define prepare_arch_switch(next) do { } while (0)
++#endif
++#ifndef finish_arch_switch
++# define finish_arch_switch(prev) do { } while (0)
++#endif
++
++/*
++ * All common locking functions performed on grq.lock. rq->clock is local to
++ * the CPU accessing it so it can be modified just with interrupts disabled
++ * when we're not updating niffies.
++ * Looking up task_rq must be done under grq.lock to be safe.
++ */
++static void update_rq_clock_task(struct rq *rq, s64 delta);
++
++static inline void update_rq_clock(struct rq *rq)
++{
++ s64 delta = sched_clock_cpu(cpu_of(rq)) - rq->clock;
++
++ rq->clock += delta;
++ update_rq_clock_task(rq, delta);
++}
++
++static inline int task_running(struct task_struct *p)
++{
++ return p->oncpu;
++}
++
++static inline void grq_lock(void)
++ __acquires(grq.lock)
++{
++ raw_spin_lock(&grq.lock);
++}
++
++static inline void grq_unlock(void)
++ __releases(grq.lock)
++{
++ raw_spin_unlock(&grq.lock);
++}
++
++static inline void grq_lock_irq(void)
++ __acquires(grq.lock)
++{
++ raw_spin_lock_irq(&grq.lock);
++}
++
++static inline void time_lock_grq(struct rq *rq)
++ __acquires(grq.lock)
++{
++ grq_lock();
++ update_clocks(rq);
++}
++
++static inline void grq_unlock_irq(void)
++ __releases(grq.lock)
++{
++ raw_spin_unlock_irq(&grq.lock);
++}
++
++static inline void grq_lock_irqsave(unsigned long *flags)
++ __acquires(grq.lock)
++{
++ raw_spin_lock_irqsave(&grq.lock, *flags);
++}
++
++static inline void grq_unlock_irqrestore(unsigned long *flags)
++ __releases(grq.lock)
++{
++ raw_spin_unlock_irqrestore(&grq.lock, *flags);
++}
++
++static inline struct rq
++*task_grq_lock(struct task_struct *p, unsigned long *flags)
++ __acquires(grq.lock)
++{
++ grq_lock_irqsave(flags);
++ return task_rq(p);
++}
++
++static inline struct rq
++*time_task_grq_lock(struct task_struct *p, unsigned long *flags)
++ __acquires(grq.lock)
++{
++ struct rq *rq = task_grq_lock(p, flags);
++ update_clocks(rq);
++ return rq;
++}
++
++static inline struct rq *task_grq_lock_irq(struct task_struct *p)
++ __acquires(grq.lock)
++{
++ grq_lock_irq();
++ return task_rq(p);
++}
++
++static inline void time_task_grq_lock_irq(struct task_struct *p)
++ __acquires(grq.lock)
++{
++ struct rq *rq = task_grq_lock_irq(p);
++ update_clocks(rq);
++}
++
++static inline void task_grq_unlock_irq(void)
++ __releases(grq.lock)
++{
++ grq_unlock_irq();
++}
++
++static inline void task_grq_unlock(unsigned long *flags)
++ __releases(grq.lock)
++{
++ grq_unlock_irqrestore(flags);
++}
++
++/**
++ * grunqueue_is_locked
++ *
++ * Returns true if the global runqueue is locked.
++ * This interface allows printk to be called with the runqueue lock
++ * held and know whether or not it is OK to wake up the klogd.
++ */
++inline int grunqueue_is_locked(void)
++{
++ return raw_spin_is_locked(&grq.lock);
++}
++
++inline void grq_unlock_wait(void)
++ __releases(grq.lock)
++{
++ smp_mb(); /* spin-unlock-wait is not a full memory barrier */
++ raw_spin_unlock_wait(&grq.lock);
++}
++
++static inline void time_grq_lock(struct rq *rq, unsigned long *flags)
++ __acquires(grq.lock)
++{
++ local_irq_save(*flags);
++ time_lock_grq(rq);
++}
++
++static inline struct rq *__task_grq_lock(struct task_struct *p)
++ __acquires(grq.lock)
++{
++ grq_lock();
++ return task_rq(p);
++}
++
++static inline void __task_grq_unlock(void)
++ __releases(grq.lock)
++{
++ grq_unlock();
++}
++
++/*
++ * Look for any tasks *anywhere* that are running nice 0 or better. We do
++ * this lockless for overhead reasons since the occasional wrong result
++ * is harmless.
++ */
++int above_background_load(void)
++{
++ struct task_struct *cpu_curr;
++ unsigned long cpu;
++
++ for_each_online_cpu(cpu) {
++ cpu_curr = cpu_rq(cpu)->curr;
++ if (unlikely(!cpu_curr))
++ continue;
++ if (PRIO_TO_NICE(cpu_curr->static_prio) < 1)
++ return 1;
++ }
++ return 0;
++}
++
++#ifndef __ARCH_WANT_UNLOCKED_CTXSW
++static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next)
++{
++}
++
++static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev)
++{
++#ifdef CONFIG_DEBUG_SPINLOCK
++ /* this is a valid case when another task releases the spinlock */
++ grq.lock.owner = current;
++#endif
++ /*
++ * If we are tracking spinlock dependencies then we have to
++ * fix up the runqueue lock - which gets 'carried over' from
++ * prev into current:
++ */
++ spin_acquire(&grq.lock.dep_map, 0, 0, _THIS_IP_);
++
++ grq_unlock_irq();
++}
++
++#else /* __ARCH_WANT_UNLOCKED_CTXSW */
++
++static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next)
++{
++#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
++ grq_unlock_irq();
++#else
++ grq_unlock();
++#endif
++}
++
++static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev)
++{
++ smp_wmb();
++#ifndef __ARCH_WANT_INTERRUPTS_ON_CTXSW
++ local_irq_enable();
++#endif
++}
++#endif /* __ARCH_WANT_UNLOCKED_CTXSW */
++
++static inline int deadline_before(u64 deadline, u64 time)
++{
++ return (deadline < time);
++}
++
++static inline int deadline_after(u64 deadline, u64 time)
++{
++ return (deadline > time);
++}
++
++/*
++ * A task that is queued but not running will be on the grq run list.
++ * A task that is not running or queued will not be on the grq run list.
++ * A task that is currently running will have ->oncpu set but not on the
++ * grq run list.
++ */
++static inline int task_queued(struct task_struct *p)
++{
++ return (!list_empty(&p->run_list));
++}
++
++/*
++ * Removing from the global runqueue. Enter with grq locked.
++ */
++static void dequeue_task(struct task_struct *p)
++{
++ list_del_init(&p->run_list);
++ if (list_empty(grq.queue + p->prio))
++ __clear_bit(p->prio, grq.prio_bitmap);
++}
++
++/*
++ * To determine if it's safe for a task of SCHED_IDLEPRIO to actually run as
++ * an idle task, we ensure none of the following conditions are met.
++ */
++static int idleprio_suitable(struct task_struct *p)
++{
++ return (!freezing(p) && !signal_pending(p) &&
++ !(task_contributes_to_load(p)) && !(p->flags & (PF_EXITING)));
++}
++
++/*
++ * To determine if a task of SCHED_ISO can run in pseudo-realtime, we check
++ * that the iso_refractory flag is not set.
++ */
++static int isoprio_suitable(void)
++{
++ return !grq.iso_refractory;
++}
++
++/*
++ * Adding to the global runqueue. Enter with grq locked.
++ */
++static void enqueue_task(struct task_struct *p)
++{
++ if (!rt_task(p)) {
++ /* Check it hasn't gotten rt from PI */
++ if ((idleprio_task(p) && idleprio_suitable(p)) ||
++ (iso_task(p) && isoprio_suitable()))
++ p->prio = p->normal_prio;
++ else
++ p->prio = NORMAL_PRIO;
++ }
++ __set_bit(p->prio, grq.prio_bitmap);
++ list_add_tail(&p->run_list, grq.queue + p->prio);
++ sched_info_queued(p);
++}
++
++/* Only idle task does this as a real time task*/
++static inline void enqueue_task_head(struct task_struct *p)
++{
++ __set_bit(p->prio, grq.prio_bitmap);
++ list_add(&p->run_list, grq.queue + p->prio);
++ sched_info_queued(p);
++}
++
++static inline void requeue_task(struct task_struct *p)
++{
++ sched_info_queued(p);
++}
++
++/*
++ * Returns the relative length of deadline all compared to the shortest
++ * deadline which is that of nice -20.
++ */
++static inline int task_prio_ratio(struct task_struct *p)
++{
++ return prio_ratios[TASK_USER_PRIO(p)];
++}
++
++/*
++ * task_timeslice - all tasks of all priorities get the exact same timeslice
++ * length. CPU distribution is handled by giving different deadlines to
++ * tasks of different priorities. Use 128 as the base value for fast shifts.
++ */
++static inline int task_timeslice(struct task_struct *p)
++{
++ return (rr_interval * task_prio_ratio(p) / 128);
++}
++
++#ifdef CONFIG_SMP
++/*
++ * qnr is the "queued but not running" count which is the total number of
++ * tasks on the global runqueue list waiting for cpu time but not actually
++ * currently running on a cpu.
++ */
++static inline void inc_qnr(void)
++{
++ grq.qnr++;
++}
++
++static inline void dec_qnr(void)
++{
++ grq.qnr--;
++}
++
++static inline int queued_notrunning(void)
++{
++ return grq.qnr;
++}
++
++/*
++ * The cpu_idle_map stores a bitmap of all the CPUs currently idle to
++ * allow easy lookup of whether any suitable idle CPUs are available.
++ * It's cheaper to maintain a binary yes/no if there are any idle CPUs on the
++ * idle_cpus variable than to do a full bitmask check when we are busy.
++ */
++static inline void set_cpuidle_map(unsigned long cpu)
++{
++ if (likely(cpu_online(cpu))) {
++ cpu_set(cpu, grq.cpu_idle_map);
++ grq.idle_cpus = 1;
++ }
++}
++
++static inline void clear_cpuidle_map(unsigned long cpu)
++{
++ cpu_clear(cpu, grq.cpu_idle_map);
++ if (cpus_empty(grq.cpu_idle_map))
++ grq.idle_cpus = 0;
++}
++
++static int suitable_idle_cpus(struct task_struct *p)
++{
++ if (!grq.idle_cpus)
++ return 0;
++ return (cpus_intersects(p->cpus_allowed, grq.cpu_idle_map));
++}
++
++static void resched_task(struct task_struct *p);
++
++#define CPUIDLE_DIFF_THREAD (1)
++#define CPUIDLE_DIFF_CORE (2)
++#define CPUIDLE_CACHE_BUSY (4)
++#define CPUIDLE_DIFF_CPU (8)
++#define CPUIDLE_THREAD_BUSY (16)
++#define CPUIDLE_DIFF_NODE (32)
++
++/*
++ * The best idle CPU is chosen according to the CPUIDLE ranking above where the
++ * lowest value would give the most suitable CPU to schedule p onto next. We
++ * iterate from the last CPU upwards instead of using for_each_cpu_mask so as
++ * to be able to break out immediately if the last CPU is idle. The order works
++ * out to be the following:
++ *
++ * Same core, idle or busy cache, idle threads
++ * Other core, same cache, idle or busy cache, idle threads.
++ * Same node, other CPU, idle cache, idle threads.
++ * Same node, other CPU, busy cache, idle threads.
++ * Same core, busy threads.
++ * Other core, same cache, busy threads.
++ * Same node, other CPU, busy threads.
++ * Other node, other CPU, idle cache, idle threads.
++ * Other node, other CPU, busy cache, idle threads.
++ * Other node, other CPU, busy threads.
++ *
++ * If p was the last task running on this rq, then regardless of where
++ * it has been running since then, it is cache warm on this rq.
++ */
++static void resched_best_idle(struct task_struct *p)
++{
++ unsigned long cpu_tmp, best_cpu, best_ranking;
++ cpumask_t tmpmask;
++ struct rq *rq;
++ int iterate;
++
++ cpus_and(tmpmask, p->cpus_allowed, grq.cpu_idle_map);
++ iterate = cpus_weight(tmpmask);
++ best_cpu = task_cpu(p);
++ /*
++ * Start below the last CPU and work up with next_cpu as the last
++ * CPU might not be idle or affinity might not allow it.
++ */
++ cpu_tmp = best_cpu - 1;
++ rq = cpu_rq(best_cpu);
++ best_ranking = ~0UL;
++
++ do {
++ unsigned long ranking;
++ struct rq *tmp_rq;
++
++ ranking = 0;
++ cpu_tmp = next_cpu(cpu_tmp, tmpmask);
++ if (cpu_tmp >= nr_cpu_ids) {
++ cpu_tmp = -1;
++ cpu_tmp = next_cpu(cpu_tmp, tmpmask);
++ }
++ tmp_rq = cpu_rq(cpu_tmp);
++
++#ifdef CONFIG_NUMA
++ if (rq->cpu_locality[cpu_tmp] > 3)
++ ranking |= CPUIDLE_DIFF_NODE;
++ else
++#endif
++ if (rq->cpu_locality[cpu_tmp] > 2)
++ ranking |= CPUIDLE_DIFF_CPU;
++#ifdef CONFIG_SCHED_MC
++ if (rq->cpu_locality[cpu_tmp] == 2)
++ ranking |= CPUIDLE_DIFF_CORE;
++ if (!(tmp_rq->cache_idle(cpu_tmp)))
++ ranking |= CPUIDLE_CACHE_BUSY;
++#endif
++#ifdef CONFIG_SCHED_SMT
++ if (rq->cpu_locality[cpu_tmp] == 1)
++ ranking |= CPUIDLE_DIFF_THREAD;
++ if (!(tmp_rq->siblings_idle(cpu_tmp)))
++ ranking |= CPUIDLE_THREAD_BUSY;
++#endif
++ if (ranking < best_ranking) {
++ best_cpu = cpu_tmp;
++ if (ranking == 0)
++ break;
++ best_ranking = ranking;
++ }
++ } while (--iterate > 0);
++
++ resched_task(cpu_rq(best_cpu)->curr);
++}
++
++static inline void resched_suitable_idle(struct task_struct *p)
++{
++ if (suitable_idle_cpus(p))
++ resched_best_idle(p);
++}
++
++/*
++ * The cpu cache locality difference between CPUs is used to determine how far
++ * to offset the virtual deadline. <2 difference in locality means that one
++ * timeslice difference is allowed longer for the cpu local tasks. This is
++ * enough in the common case when tasks are up to 2* number of CPUs to keep
++ * tasks within their shared cache CPUs only. CPUs on different nodes or not
++ * even in this domain (NUMA) have "4" difference, allowing 4 times longer
++ * deadlines before being taken onto another cpu, allowing for 2* the double
++ * seen by separate CPUs above.
++ * Simple summary: Virtual deadlines are equal on shared cache CPUs, double
++ * on separate CPUs and quadruple in separate NUMA nodes.
++ */
++static inline int
++cache_distance(struct rq *task_rq, struct rq *rq, struct task_struct *p)
++{
++ int locality = rq->cpu_locality[cpu_of(task_rq)] - 2;
++
++ if (locality > 0)
++ return task_timeslice(p) << locality;
++ return 0;
++}
++#else /* CONFIG_SMP */
++static inline void inc_qnr(void)
++{
++}
++
++static inline void dec_qnr(void)
++{
++}
++
++static inline int queued_notrunning(void)
++{
++ return grq.nr_running;
++}
++
++static inline void set_cpuidle_map(unsigned long cpu)
++{
++}
++
++static inline void clear_cpuidle_map(unsigned long cpu)
++{
++}
++
++static inline int suitable_idle_cpus(struct task_struct *p)
++{
++ return uprq->curr == uprq->idle;
++}
++
++static inline void resched_suitable_idle(struct task_struct *p)
++{
++}
++
++static inline int
++cache_distance(struct rq *task_rq, struct rq *rq, struct task_struct *p)
++{
++ return 0;
++}
++#endif /* CONFIG_SMP */
++
++/*
++ * activate_idle_task - move idle task to the _front_ of runqueue.
++ */
++static inline void activate_idle_task(struct task_struct *p)
++{
++ enqueue_task_head(p);
++ grq.nr_running++;
++ inc_qnr();
++}
++
++static inline int normal_prio(struct task_struct *p)
++{
++ if (has_rt_policy(p))
++ return MAX_RT_PRIO - 1 - p->rt_priority;
++ if (idleprio_task(p))
++ return IDLE_PRIO;
++ if (iso_task(p))
++ return ISO_PRIO;
++ return NORMAL_PRIO;
++}
++
++/*
++ * Calculate the current priority, i.e. the priority
++ * taken into account by the scheduler. This value might
++ * be boosted by RT tasks as it will be RT if the task got
++ * RT-boosted. If not then it returns p->normal_prio.
++ */
++static int effective_prio(struct task_struct *p)
++{
++ p->normal_prio = normal_prio(p);
++ /*
++ * If we are RT tasks or we were boosted to RT priority,
++ * keep the priority unchanged. Otherwise, update priority
++ * to the normal priority:
++ */
++ if (!rt_prio(p->prio))
++ return p->normal_prio;
++ return p->prio;
++}
++
++/*
++ * activate_task - move a task to the runqueue. Enter with grq locked.
++ */
++static void activate_task(struct task_struct *p, struct rq *rq)
++{
++ update_clocks(rq);
++
++ /*
++ * Sleep time is in units of nanosecs, so shift by 20 to get a
++ * milliseconds-range estimation of the amount of time that the task
++ * spent sleeping:
++ */
++ if (unlikely(prof_on == SLEEP_PROFILING)) {
++ if (p->state == TASK_UNINTERRUPTIBLE)
++ profile_hits(SLEEP_PROFILING, (void *)get_wchan(p),
++ (rq->clock - p->last_ran) >> 20);
++ }
++
++ p->prio = effective_prio(p);
++ if (task_contributes_to_load(p))
++ grq.nr_uninterruptible--;
++ enqueue_task(p);
++ grq.nr_running++;
++ inc_qnr();
++}
++
++/*
++ * deactivate_task - If it's running, it's not on the grq and we can just
++ * decrement the nr_running. Enter with grq locked.
++ */
++static inline void deactivate_task(struct task_struct *p)
++{
++ if (task_contributes_to_load(p))
++ grq.nr_uninterruptible++;
++ grq.nr_running--;
++}
++
++#ifdef CONFIG_SMP
++void set_task_cpu(struct task_struct *p, unsigned int cpu)
++{
++ trace_sched_migrate_task(p, cpu);
++ if (task_cpu(p) != cpu)
++ perf_sw_event(PERF_COUNT_SW_CPU_MIGRATIONS, 1, 1, NULL, 0);
++
++ /*
++ * After ->cpu is set up to a new value, task_grq_lock(p, ...) can be
++ * successfuly executed on another CPU. We must ensure that updates of
++ * per-task data have been completed by this moment.
++ */
++ smp_wmb();
++ task_thread_info(p)->cpu = cpu;
++}
++#endif
++
++/*
++ * Move a task off the global queue and take it to a cpu for it will
++ * become the running task.
++ */
++static inline void take_task(struct rq *rq, struct task_struct *p)
++{
++ set_task_cpu(p, cpu_of(rq));
++ dequeue_task(p);
++ dec_qnr();
++}
++
++/*
++ * Returns a descheduling task to the grq runqueue unless it is being
++ * deactivated.
++ */
++static inline void return_task(struct task_struct *p, int deactivate)
++{
++ if (deactivate)
++ deactivate_task(p);
++ else {
++ inc_qnr();
++ enqueue_task(p);
++ }
++}
++
++/*
++ * resched_task - mark a task 'to be rescheduled now'.
++ *
++ * On UP this means the setting of the need_resched flag, on SMP it
++ * might also involve a cross-CPU call to trigger the scheduler on
++ * the target CPU.
++ */
++#ifdef CONFIG_SMP
++
++#ifndef tsk_is_polling
++#define tsk_is_polling(t) test_tsk_thread_flag(t, TIF_POLLING_NRFLAG)
++#endif
++
++static void resched_task(struct task_struct *p)
++{
++ int cpu;
++
++ assert_raw_spin_locked(&grq.lock);
++
++ if (unlikely(test_tsk_thread_flag(p, TIF_NEED_RESCHED)))
++ return;
++
++ set_tsk_thread_flag(p, TIF_NEED_RESCHED);
++
++ cpu = task_cpu(p);
++ if (cpu == smp_processor_id())
++ return;
++
++ /* NEED_RESCHED must be visible before we test polling */
++ smp_mb();
++ if (!tsk_is_polling(p))
++ smp_send_reschedule(cpu);
++}
++
++#else
++static inline void resched_task(struct task_struct *p)
++{
++ assert_raw_spin_locked(&grq.lock);
++ set_tsk_need_resched(p);
++}
++#endif
++
++/**
++ * task_curr - is this task currently executing on a CPU?
++ * @p: the task in question.
++ */
++inline int task_curr(const struct task_struct *p)
++{
++ return cpu_curr(task_cpu(p)) == p;
++}
++
++#ifdef CONFIG_SMP
++struct migration_req {
++ struct task_struct *task;
++ int dest_cpu;
++};
++
++/*
++ * wait_task_inactive - wait for a thread to unschedule.
++ *
++ * If @match_state is nonzero, it's the @p->state value just checked and
++ * not expected to change. If it changes, i.e. @p might have woken up,
++ * then return zero. When we succeed in waiting for @p to be off its CPU,
++ * we return a positive number (its total switch count). If a second call
++ * a short while later returns the same number, the caller can be sure that
++ * @p has remained unscheduled the whole time.
++ *
++ * The caller must ensure that the task *will* unschedule sometime soon,
++ * else this function might spin for a *long* time. This function can't
++ * be called with interrupts off, or it may introduce deadlock with
++ * smp_call_function() if an IPI is sent by the same process we are
++ * waiting to become inactive.
++ */
++unsigned long wait_task_inactive(struct task_struct *p, long match_state)
++{
++ unsigned long flags;
++ int running, on_rq;
++ unsigned long ncsw;
++ struct rq *rq;
++
++ for (;;) {
++ /*
++ * We do the initial early heuristics without holding
++ * any task-queue locks at all. We'll only try to get
++ * the runqueue lock when things look like they will
++ * work out! In the unlikely event rq is dereferenced
++ * since we're lockless, grab it again.
++ */
++#ifdef CONFIG_SMP
++retry_rq:
++ rq = task_rq(p);
++ if (unlikely(!rq))
++ goto retry_rq;
++#else /* CONFIG_SMP */
++ rq = task_rq(p);
++#endif
++ /*
++ * If the task is actively running on another CPU
++ * still, just relax and busy-wait without holding
++ * any locks.
++ *
++ * NOTE! Since we don't hold any locks, it's not
++ * even sure that "rq" stays as the right runqueue!
++ * But we don't care, since this will return false
++ * if the runqueue has changed and p is actually now
++ * running somewhere else!
++ */
++ while (task_running(p) && p == rq->curr) {
++ if (match_state && unlikely(p->state != match_state))
++ return 0;
++ cpu_relax();
++ }
++
++ /*
++ * Ok, time to look more closely! We need the grq
++ * lock now, to be *sure*. If we're wrong, we'll
++ * just go back and repeat.
++ */
++ rq = task_grq_lock(p, &flags);
++ trace_sched_wait_task(p);
++ running = task_running(p);
++ on_rq = task_queued(p);
++ ncsw = 0;
++ if (!match_state || p->state == match_state)
++ ncsw = p->nvcsw | LONG_MIN; /* sets MSB */
++ task_grq_unlock(&flags);
++
++ /*
++ * If it changed from the expected state, bail out now.
++ */
++ if (unlikely(!ncsw))
++ break;
++
++ /*
++ * Was it really running after all now that we
++ * checked with the proper locks actually held?
++ *
++ * Oops. Go back and try again..
++ */
++ if (unlikely(running)) {
++ cpu_relax();
++ continue;
++ }
++
++ /*
++ * It's not enough that it's not actively running,
++ * it must be off the runqueue _entirely_, and not
++ * preempted!
++ *
++ * So if it was still runnable (but just not actively
++ * running right now), it's preempted, and we should
++ * yield - it could be a while.
++ */
++ if (unlikely(on_rq)) {
++ schedule_timeout_uninterruptible(1);
++ continue;
++ }
++
++ /*
++ * Ahh, all good. It wasn't running, and it wasn't
++ * runnable, which means that it will never become
++ * running in the future either. We're all done!
++ */
++ break;
++ }
++
++ return ncsw;
++}
++
++/***
++ * kick_process - kick a running thread to enter/exit the kernel
++ * @p: the to-be-kicked thread
++ *
++ * Cause a process which is running on another CPU to enter
++ * kernel-mode, without any delay. (to get signals handled.)
++ *
++ * NOTE: this function doesnt have to take the runqueue lock,
++ * because all it wants to ensure is that the remote task enters
++ * the kernel. If the IPI races and the task has been migrated
++ * to another CPU then no harm is done and the purpose has been
++ * achieved as well.
++ */
++void kick_process(struct task_struct *p)
++{
++ int cpu;
++
++ preempt_disable();
++ cpu = task_cpu(p);
++ if ((cpu != smp_processor_id()) && task_curr(p))
++ smp_send_reschedule(cpu);
++ preempt_enable();
++}
++EXPORT_SYMBOL_GPL(kick_process);
++#endif
++
++#define rq_idle(rq) ((rq)->rq_prio == PRIO_LIMIT)
++
++/*
++ * RT tasks preempt purely on priority. SCHED_NORMAL tasks preempt on the
++ * basis of earlier deadlines. SCHED_IDLEPRIO don't preempt anything else or
++ * between themselves, they cooperatively multitask. An idle rq scores as
++ * prio PRIO_LIMIT so it is always preempted.
++ */
++static inline int
++can_preempt(struct task_struct *p, int prio, u64 deadline,
++ unsigned int policy)
++{
++ /* Better static priority RT task or better policy preemption */
++ if (p->prio < prio)
++ return 1;
++ if (p->prio > prio)
++ return 0;
++ /* SCHED_NORMAL, BATCH and ISO will preempt based on deadline */
++ if (!deadline_before(p->deadline, deadline))
++ return 0;
++ return 1;
++}
++#ifdef CONFIG_SMP
++#ifdef CONFIG_HOTPLUG_CPU
++/*
++ * Check to see if there is a task that is affined only to offline CPUs but
++ * still wants runtime. This happens to kernel threads during suspend/halt and
++ * disabling of CPUs.
++ */
++static inline int online_cpus(struct task_struct *p)
++{
++ return (likely(cpus_intersects(cpu_online_map, p->cpus_allowed)));
++}
++#else /* CONFIG_HOTPLUG_CPU */
++/* All available CPUs are always online without hotplug. */
++static inline int online_cpus(struct task_struct *p)
++{
++ return 1;
++}
++#endif
++
++/*
++ * Check to see if p can run on cpu, and if not, whether there are any online
++ * CPUs it can run on instead.
++ */
++static inline int needs_other_cpu(struct task_struct *p, int cpu)
++{
++ if (unlikely(!cpu_isset(cpu, p->cpus_allowed)))
++ return 1;
++ return 0;
++}
++
++/*
++ * latest_deadline and highest_prio_rq are initialised only to silence the
++ * compiler. When all else is equal, still prefer this_rq.
++ */
++static void try_preempt(struct task_struct *p, struct rq *this_rq)
++{
++ struct rq *highest_prio_rq = this_rq;
++ u64 latest_deadline;
++ unsigned long cpu;
++ int highest_prio;
++ cpumask_t tmp;
++
++ if (suitable_idle_cpus(p)) {
++ resched_best_idle(p);
++ return;
++ }
++
++ /* IDLEPRIO tasks never preempt anything */
++ if (p->policy == SCHED_IDLEPRIO)
++ return;
++
++ if (likely(online_cpus(p)))
++ cpus_and(tmp, cpu_online_map, p->cpus_allowed);
++ else
++ return;
++
++ latest_deadline = 0;
++ highest_prio = -1;
++
++ for_each_cpu_mask(cpu, tmp) {
++ u64 offset_deadline;
++ struct rq *rq;
++ int rq_prio;
++
++ rq = cpu_rq(cpu);
++ rq_prio = rq->rq_prio;
++ if (rq_prio < highest_prio)
++ continue;
++
++ offset_deadline = rq->rq_deadline -
++ cache_distance(this_rq, rq, p);
++
++ if (rq_prio > highest_prio || (rq_prio == highest_prio &&
++ deadline_after(offset_deadline, latest_deadline))) {
++ latest_deadline = offset_deadline;
++ highest_prio = rq_prio;
++ highest_prio_rq = rq;
++ }
++ }
++
++ if (!can_preempt(p, highest_prio, highest_prio_rq->rq_deadline,
++ highest_prio_rq->rq_policy))
++ return;
++
++ resched_task(highest_prio_rq->curr);
++}
++#else /* CONFIG_SMP */
++static inline int needs_other_cpu(struct task_struct *p, int cpu)
++{
++ return 0;
++}
++
++static void try_preempt(struct task_struct *p, struct rq *this_rq)
++{
++ if (p->policy == SCHED_IDLEPRIO)
++ return;
++ if (can_preempt(p, uprq->rq_prio, uprq->rq_deadline,
++ uprq->rq_policy))
++ resched_task(uprq->curr);
++}
++#endif /* CONFIG_SMP */
++
++/**
++ * task_oncpu_function_call - call a function on the cpu on which a task runs
++ * @p: the task to evaluate
++ * @func: the function to be called
++ * @info: the function call argument
++ *
++ * Calls the function @func when the task is currently running. This might
++ * be on the current CPU, which just calls the function directly
++ */
++void task_oncpu_function_call(struct task_struct *p,
++ void (*func) (void *info), void *info)
++{
++ int cpu;
++
++ preempt_disable();
++ cpu = task_cpu(p);
++ if (task_curr(p))
++ smp_call_function_single(cpu, func, info, 1);
++ preempt_enable();
++}
++
++static inline void ttwu_activate(struct task_struct *p, struct rq *rq,
++ bool is_sync)
++{
++ activate_task(p, rq);
++
++ /*
++ * Sync wakeups (i.e. those types of wakeups where the waker
++ * has indicated that it will leave the CPU in short order)
++ * don't trigger a preemption if there are no idle cpus,
++ * instead waiting for current to deschedule.
++ */
++ if (!is_sync || suitable_idle_cpus(p))
++ try_preempt(p, rq);
++}
++
++static inline void ttwu_post_activation(struct task_struct *p, struct rq *rq,
++ bool success)
++{
++ trace_sched_wakeup(p, success);
++ p->state = TASK_RUNNING;
++
++ /*
++ * if a worker is waking up, notify workqueue. Note that on BFS, we
++ * don't really know what cpu it will be, so we fake it for
++ * wq_worker_waking_up :/
++ */
++ if ((p->flags & PF_WQ_WORKER) && success)
++ wq_worker_waking_up(p, cpu_of(rq));
++}
++
++/***
++ * try_to_wake_up - wake up a thread
++ * @p: the thread to be awakened
++ * @state: the mask of task states that can be woken
++ * @wake_flags: wake modifier flags (WF_*)
++ *
++ * Put it on the run-queue if it's not already there. The "current"
++ * thread is always on the run-queue (except when the actual
++ * re-schedule is in progress), and as such you're allowed to do
++ * the simpler "current->state = TASK_RUNNING" to mark yourself
++ * runnable without the overhead of this.
++ *
++ * Returns %true if @p was woken up, %false if it was already running
++ * or @state didn't match @p's state.
++ */
++static int try_to_wake_up(struct task_struct *p, unsigned int state,
++ int wake_flags)
++{
++ unsigned long flags;
++ int success = 0;
++ struct rq *rq;
++
++ get_cpu();
++
++ /* This barrier is undocumented, probably for p->state? くそ */
++ smp_wmb();
++
++ /*
++ * No need to do time_lock_grq as we only need to update the rq clock
++ * if we activate the task
++ */
++ rq = task_grq_lock(p, &flags);
++
++ /* state is a volatile long, どうして、分からない */
++ if (!((unsigned int)p->state & state))
++ goto out_unlock;
++
++ if (task_queued(p) || task_running(p))
++ goto out_running;
++
++ ttwu_activate(p, rq, wake_flags & WF_SYNC);
++ success = true;
++
++out_running:
++ ttwu_post_activation(p, rq, success);
++out_unlock:
++ task_grq_unlock(&flags);
++ put_cpu();
++
++ return success;
++}
++
++/**
++ * try_to_wake_up_local - try to wake up a local task with grq lock held
++ * @p: the thread to be awakened
++ *
++ * Put @p on the run-queue if it's not already there. The caller must
++ * ensure that grq is locked and, @p is not the current task.
++ * grq stays locked over invocation.
++ */
++static void try_to_wake_up_local(struct task_struct *p)
++{
++ struct rq *rq = task_rq(p);
++ bool success = false;
++
++ WARN_ON(rq != this_rq());
++ BUG_ON(p == current);
++ lockdep_assert_held(&grq.lock);
++
++ if (!(p->state & TASK_NORMAL))
++ return;
++
++ if (!task_queued(p)) {
++ if (likely(!task_running(p))) {
++ schedstat_inc(rq, ttwu_count);
++ schedstat_inc(rq, ttwu_local);
++ }
++ ttwu_activate(p, rq, false);
++ success = true;
++ }
++ ttwu_post_activation(p, rq, success);
++}
++
++/**
++ * wake_up_process - Wake up a specific process
++ * @p: The process to be woken up.
++ *
++ * Attempt to wake up the nominated process and move it to the set of runnable
++ * processes. Returns 1 if the process was woken up, 0 if it was already
++ * running.
++ *
++ * It may be assumed that this function implies a write memory barrier before
++ * changing the task state if and only if any tasks are woken up.
++ */
++int wake_up_process(struct task_struct *p)
++{
++ return try_to_wake_up(p, TASK_ALL, 0);
++}
++EXPORT_SYMBOL(wake_up_process);
++
++int wake_up_state(struct task_struct *p, unsigned int state)
++{
++ return try_to_wake_up(p, state, 0);
++}
++
++static void time_slice_expired(struct task_struct *p);
++
++/*
++ * Perform scheduler related setup for a newly forked process p.
++ * p is forked by current.
++ */
++void sched_fork(struct task_struct *p, int clone_flags)
++{
++ struct task_struct *curr;
++ int cpu = get_cpu();
++ struct rq *rq;
++
++#ifdef CONFIG_PREEMPT_NOTIFIERS
++ INIT_HLIST_HEAD(&p->preempt_notifiers);
++#endif
++ /*
++ * We mark the process as running here. This guarantees that
++ * nobody will actually run it, and a signal or other external
++ * event cannot wake it up and insert it on the runqueue either.
++ */
++ p->state = TASK_RUNNING;
++ set_task_cpu(p, cpu);
++
++ /* Should be reset in fork.c but done here for ease of bfs patching */
++ p->sched_time = p->stime_pc = p->utime_pc = 0;
++
++ /*
++ * Revert to default priority/policy on fork if requested.
++ */
++ if (unlikely(p->sched_reset_on_fork)) {
++ if (p->policy == SCHED_FIFO || p->policy == SCHED_RR) {
++ p->policy = SCHED_NORMAL;
++ p->normal_prio = normal_prio(p);
++ }
++
++ if (PRIO_TO_NICE(p->static_prio) < 0) {
++ p->static_prio = NICE_TO_PRIO(0);
++ p->normal_prio = p->static_prio;
++ }
++
++ /*
++ * We don't need the reset flag anymore after the fork. It has
++ * fulfilled its duty:
++ */
++ p->sched_reset_on_fork = 0;
++ }
++
++ curr = current;
++ /*
++ * Make sure we do not leak PI boosting priority to the child.
++ */
++ p->prio = curr->normal_prio;
++
++ INIT_LIST_HEAD(&p->run_list);
++#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
++ if (unlikely(sched_info_on()))
++ memset(&p->sched_info, 0, sizeof(p->sched_info));
++#endif
++
++ p->oncpu = 0;
++
++#ifdef CONFIG_PREEMPT
++ /* Want to start with kernel preemption disabled. */
++ task_thread_info(p)->preempt_count = 1;
++#endif
++ if (unlikely(p->policy == SCHED_FIFO))
++ goto out;
++ /*
++ * Share the timeslice between parent and child, thus the
++ * total amount of pending timeslices in the system doesn't change,
++ * resulting in more scheduling fairness. If it's negative, it won't
++ * matter since that's the same as being 0. current's time_slice is
++ * actually in rq_time_slice when it's running, as is its last_ran
++ * value. rq->rq_deadline is only modified within schedule() so it
++ * is always equal to current->deadline.
++ */
++ rq = task_grq_lock_irq(curr);
++ if (likely(rq->rq_time_slice >= RESCHED_US * 2)) {
++ rq->rq_time_slice /= 2;
++ p->time_slice = rq->rq_time_slice;
++ } else {
++ /*
++ * Forking task has run out of timeslice. Reschedule it and
++ * start its child with a new time slice and deadline. The
++ * child will end up running first because its deadline will
++ * be slightly earlier.
++ */
++ rq->rq_time_slice = 0;
++ set_tsk_need_resched(curr);
++ time_slice_expired(p);
++ }
++ p->last_ran = rq->rq_last_ran;
++ task_grq_unlock_irq();
++out:
++ put_cpu();
++}
++
++/*
++ * wake_up_new_task - wake up a newly created task for the first time.
++ *
++ * This function will do some initial scheduler statistics housekeeping
++ * that must be done for every newly created context, then puts the task
++ * on the runqueue and wakes it.
++ */
++void wake_up_new_task(struct task_struct *p, unsigned long clone_flags)
++{
++ struct task_struct *parent;
++ unsigned long flags;
++ struct rq *rq;
++
++ rq = task_grq_lock(p, &flags);
++ p->state = TASK_RUNNING;
++ parent = p->parent;
++ /* Unnecessary but small chance that the parent changed CPU */
++ set_task_cpu(p, task_cpu(parent));
++ activate_task(p, rq);
++ trace_sched_wakeup_new(p, 1);
++ if (!(clone_flags & CLONE_VM) && rq->curr == parent &&
++ !suitable_idle_cpus(p)) {
++ /*
++ * The VM isn't cloned, so we're in a good position to
++ * do child-runs-first in anticipation of an exec. This
++ * usually avoids a lot of COW overhead.
++ */
++ resched_task(parent);
++ } else
++ try_preempt(p, rq);
++ task_grq_unlock(&flags);
++}
++
++#ifdef CONFIG_PREEMPT_NOTIFIERS
++
++/**
++ * preempt_notifier_register - tell me when current is being preempted & rescheduled
++ * @notifier: notifier struct to register
++ */
++void preempt_notifier_register(struct preempt_notifier *notifier)
++{
++ hlist_add_head(&notifier->link, &current->preempt_notifiers);
++}
++EXPORT_SYMBOL_GPL(preempt_notifier_register);
++
++/**
++ * preempt_notifier_unregister - no longer interested in preemption notifications
++ * @notifier: notifier struct to unregister
++ *
++ * This is safe to call from within a preemption notifier.
++ */
++void preempt_notifier_unregister(struct preempt_notifier *notifier)
++{
++ hlist_del(&notifier->link);
++}
++EXPORT_SYMBOL_GPL(preempt_notifier_unregister);
++
++static void fire_sched_in_preempt_notifiers(struct task_struct *curr)
++{
++ struct preempt_notifier *notifier;
++ struct hlist_node *node;
++
++ hlist_for_each_entry(notifier, node, &curr->preempt_notifiers, link)
++ notifier->ops->sched_in(notifier, raw_smp_processor_id());
++}
++
++static void
++fire_sched_out_preempt_notifiers(struct task_struct *curr,
++ struct task_struct *next)
++{
++ struct preempt_notifier *notifier;
++ struct hlist_node *node;
++
++ hlist_for_each_entry(notifier, node, &curr->preempt_notifiers, link)
++ notifier->ops->sched_out(notifier, next);
++}
++
++#else /* !CONFIG_PREEMPT_NOTIFIERS */
++
++static void fire_sched_in_preempt_notifiers(struct task_struct *curr)
++{
++}
++
++static void
++fire_sched_out_preempt_notifiers(struct task_struct *curr,
++ struct task_struct *next)
++{
++}
++
++#endif /* CONFIG_PREEMPT_NOTIFIERS */
++
++/**
++ * prepare_task_switch - prepare to switch tasks
++ * @rq: the runqueue preparing to switch
++ * @next: the task we are going to switch to.
++ *
++ * This is called with the rq lock held and interrupts off. It must
++ * be paired with a subsequent finish_task_switch after the context
++ * switch.
++ *
++ * prepare_task_switch sets up locking and calls architecture specific
++ * hooks.
++ */
++static inline void
++prepare_task_switch(struct rq *rq, struct task_struct *prev,
++ struct task_struct *next)
++{
++ fire_sched_out_preempt_notifiers(prev, next);
++ prepare_lock_switch(rq, next);
++ prepare_arch_switch(next);
++}
++
++/**
++ * finish_task_switch - clean up after a task-switch
++ * @rq: runqueue associated with task-switch
++ * @prev: the thread we just switched away from.
++ *
++ * finish_task_switch must be called after the context switch, paired
++ * with a prepare_task_switch call before the context switch.
++ * finish_task_switch will reconcile locking set up by prepare_task_switch,
++ * and do any other architecture-specific cleanup actions.
++ *
++ * Note that we may have delayed dropping an mm in context_switch(). If
++ * so, we finish that here outside of the runqueue lock. (Doing it
++ * with the lock held can cause deadlocks; see schedule() for
++ * details.)
++ */
++static inline void finish_task_switch(struct rq *rq, struct task_struct *prev)
++ __releases(grq.lock)
++{
++ struct mm_struct *mm = rq->prev_mm;
++ long prev_state;
++
++ rq->prev_mm = NULL;
++
++ /*
++ * A task struct has one reference for the use as "current".
++ * If a task dies, then it sets TASK_DEAD in tsk->state and calls
++ * schedule one last time. The schedule call will never return, and
++ * the scheduled task must drop that reference.
++ * The test for TASK_DEAD must occur while the runqueue locks are
++ * still held, otherwise prev could be scheduled on another cpu, die
++ * there before we look at prev->state, and then the reference would
++ * be dropped twice.
++ * Manfred Spraul <manfred@colorfullife.com>
++ */
++ prev_state = prev->state;
++ finish_arch_switch(prev);
++#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
++ local_irq_disable();
++#endif /* __ARCH_WANT_INTERRUPTS_ON_CTXSW */
++ perf_event_task_sched_in(current);
++#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
++ local_irq_enable();
++#endif /* __ARCH_WANT_INTERRUPTS_ON_CTXSW */
++ finish_lock_switch(rq, prev);
++
++ fire_sched_in_preempt_notifiers(current);
++ if (mm)
++ mmdrop(mm);
++ if (unlikely(prev_state == TASK_DEAD)) {
++ /*
++ * Remove function-return probe instances associated with this
++ * task and put them back on the free list.
++ */
++ kprobe_flush_task(prev);
++ put_task_struct(prev);
++ }
++}
++
++/**
++ * schedule_tail - first thing a freshly forked thread must call.
++ * @prev: the thread we just switched away from.
++ */
++asmlinkage void schedule_tail(struct task_struct *prev)
++ __releases(grq.lock)
++{
++ struct rq *rq = this_rq();
++
++ finish_task_switch(rq, prev);
++#ifdef __ARCH_WANT_UNLOCKED_CTXSW
++ /* In this case, finish_task_switch does not reenable preemption */
++ preempt_enable();
++#endif
++ if (current->set_child_tid)
++ put_user(current->pid, current->set_child_tid);
++}
++
++/*
++ * context_switch - switch to the new MM and the new
++ * thread's register state.
++ */
++static inline void
++context_switch(struct rq *rq, struct task_struct *prev,
++ struct task_struct *next)
++{
++ struct mm_struct *mm, *oldmm;
++
++ prepare_task_switch(rq, prev, next);
++ trace_sched_switch(prev, next);
++ mm = next->mm;
++ oldmm = prev->active_mm;
++ /*
++ * For paravirt, this is coupled with an exit in switch_to to
++ * combine the page table reload and the switch backend into
++ * one hypercall.
++ */
++ arch_start_context_switch(prev);
++
++ if (!mm) {
++ next->active_mm = oldmm;
++ atomic_inc(&oldmm->mm_count);
++ enter_lazy_tlb(oldmm, next);
++ } else
++ switch_mm(oldmm, mm, next);
++
++ if (!prev->mm) {
++ prev->active_mm = NULL;
++ rq->prev_mm = oldmm;
++ }
++ /*
++ * Since the runqueue lock will be released by the next
++ * task (which is an invalid locking op but in the case
++ * of the scheduler it's an obvious special-case), so we
++ * do an early lockdep release here:
++ */
++#ifndef __ARCH_WANT_UNLOCKED_CTXSW
++ spin_release(&grq.lock.dep_map, 1, _THIS_IP_);
++#endif
++
++ /* Here we just switch the register state and the stack. */
++ switch_to(prev, next, prev);
++
++ barrier();
++ /*
++ * this_rq must be evaluated again because prev may have moved
++ * CPUs since it called schedule(), thus the 'rq' on its stack
++ * frame will be invalid.
++ */
++ finish_task_switch(this_rq(), prev);
++}
++
++/*
++ * nr_running, nr_uninterruptible and nr_context_switches:
++ *
++ * externally visible scheduler statistics: current number of runnable
++ * threads, current number of uninterruptible-sleeping threads, total
++ * number of context switches performed since bootup. All are measured
++ * without grabbing the grq lock but the occasional inaccurate result
++ * doesn't matter so long as it's positive.
++ */
++unsigned long nr_running(void)
++{
++ long nr = grq.nr_running;
++
++ if (unlikely(nr < 0))
++ nr = 0;
++ return (unsigned long)nr;
++}
++
++unsigned long nr_uninterruptible(void)
++{
++ long nu = grq.nr_uninterruptible;
++
++ if (unlikely(nu < 0))
++ nu = 0;
++ return nu;
++}
++
++unsigned long long nr_context_switches(void)
++{
++ long long ns = grq.nr_switches;
++
++ /* This is of course impossible */
++ if (unlikely(ns < 0))
++ ns = 1;
++ return (long long)ns;
++}
++
++unsigned long nr_iowait(void)
++{
++ unsigned long i, sum = 0;
++
++ for_each_possible_cpu(i)
++ sum += atomic_read(&cpu_rq(i)->nr_iowait);
++
++ return sum;
++}
++
++unsigned long nr_iowait_cpu(int cpu)
++{
++ struct rq *this = cpu_rq(cpu);
++ return atomic_read(&this->nr_iowait);
++}
++
++unsigned long nr_active(void)
++{
++ return nr_running() + nr_uninterruptible();
++}
++
++/* Beyond a task running on this CPU, load is equal everywhere on BFS */
++unsigned long this_cpu_load(void)
++{
++ return this_rq()->rq_running +
++ (queued_notrunning() + nr_uninterruptible()) /
++ (1 + num_online_cpus());
++}
++
++/* Variables and functions for calc_load */
++static unsigned long calc_load_update;
++unsigned long avenrun[3];
++EXPORT_SYMBOL(avenrun);
++
++/**
++ * get_avenrun - get the load average array
++ * @loads: pointer to dest load array
++ * @offset: offset to add
++ * @shift: shift count to shift the result left
++ *
++ * These values are estimates at best, so no need for locking.
++ */
++void get_avenrun(unsigned long *loads, unsigned long offset, int shift)
++{
++ loads[0] = (avenrun[0] + offset) << shift;
++ loads[1] = (avenrun[1] + offset) << shift;
++ loads[2] = (avenrun[2] + offset) << shift;
++}
++
++static unsigned long
++calc_load(unsigned long load, unsigned long exp, unsigned long active)
++{
++ load *= exp;
++ load += active * (FIXED_1 - exp);
++ return load >> FSHIFT;
++}
++
++/*
++ * calc_load - update the avenrun load estimates every LOAD_FREQ seconds.
++ */
++void calc_global_load(unsigned long ticks)
++{
++ long active;
++
++ if (time_before(jiffies, calc_load_update))
++ return;
++ active = nr_active() * FIXED_1;
++
++ avenrun[0] = calc_load(avenrun[0], EXP_1, active);
++ avenrun[1] = calc_load(avenrun[1], EXP_5, active);
++ avenrun[2] = calc_load(avenrun[2], EXP_15, active);
++
++ calc_load_update = jiffies + LOAD_FREQ;
++}
++
++DEFINE_PER_CPU(struct kernel_stat, kstat);
++
++EXPORT_PER_CPU_SYMBOL(kstat);
++
++#ifdef CONFIG_IRQ_TIME_ACCOUNTING
++
++/*
++ * There are no locks covering percpu hardirq/softirq time.
++ * They are only modified in account_system_vtime, on corresponding CPU
++ * with interrupts disabled. So, writes are safe.
++ * They are read and saved off onto struct rq in update_rq_clock().
++ * This may result in other CPU reading this CPU's irq time and can
++ * race with irq/account_system_vtime on this CPU. We would either get old
++ * or new value with a side effect of accounting a slice of irq time to wrong
++ * task when irq is in progress while we read rq->clock. That is a worthy
++ * compromise in place of having locks on each irq in account_system_time.
++ */
++static DEFINE_PER_CPU(u64, cpu_hardirq_time);
++static DEFINE_PER_CPU(u64, cpu_softirq_time);
++
++static DEFINE_PER_CPU(u64, irq_start_time);
++static int sched_clock_irqtime;
++
++void enable_sched_clock_irqtime(void)
++{
++ sched_clock_irqtime = 1;
++}
++
++void disable_sched_clock_irqtime(void)
++{
++ sched_clock_irqtime = 0;
++}
++
++#ifndef CONFIG_64BIT
++static DEFINE_PER_CPU(seqcount_t, irq_time_seq);
++
++static inline void irq_time_write_begin(void)
++{
++ __this_cpu_inc(irq_time_seq.sequence);
++ smp_wmb();
++}
++
++static inline void irq_time_write_end(void)
++{
++ smp_wmb();
++ __this_cpu_inc(irq_time_seq.sequence);
++}
++
++static inline u64 irq_time_read(int cpu)
++{
++ u64 irq_time;
++ unsigned seq;
++
++ do {
++ seq = read_seqcount_begin(&per_cpu(irq_time_seq, cpu));
++ irq_time = per_cpu(cpu_softirq_time, cpu) +
++ per_cpu(cpu_hardirq_time, cpu);
++ } while (read_seqcount_retry(&per_cpu(irq_time_seq, cpu), seq));
++
++ return irq_time;
++}
++#else /* CONFIG_64BIT */
++static inline void irq_time_write_begin(void)
++{
++}
++
++static inline void irq_time_write_end(void)
++{
++}
++
++static inline u64 irq_time_read(int cpu)
++{
++ return per_cpu(cpu_softirq_time, cpu) + per_cpu(cpu_hardirq_time, cpu);
++}
++#endif /* CONFIG_64BIT */
++
++/*
++ * Called before incrementing preempt_count on {soft,}irq_enter
++ * and before decrementing preempt_count on {soft,}irq_exit.
++ */
++void account_system_vtime(struct task_struct *curr)
++{
++ unsigned long flags;
++ s64 delta;
++ int cpu;
++
++ if (!sched_clock_irqtime)
++ return;
++
++ local_irq_save(flags);
++
++ cpu = smp_processor_id();
++ delta = sched_clock_cpu(cpu) - __this_cpu_read(irq_start_time);
++ __this_cpu_add(irq_start_time, delta);
++
++ irq_time_write_begin();
++ /*
++ * We do not account for softirq time from ksoftirqd here.
++ * We want to continue accounting softirq time to ksoftirqd thread
++ * in that case, so as not to confuse scheduler with a special task
++ * that do not consume any time, but still wants to run.
++ */
++ if (hardirq_count())
++ __this_cpu_add(cpu_hardirq_time, delta);
++ else if (in_serving_softirq() && !(curr->flags & PF_KSOFTIRQD))
++ __this_cpu_add(cpu_softirq_time, delta);
++
++ irq_time_write_end();
++ local_irq_restore(flags);
++}
++EXPORT_SYMBOL_GPL(account_system_vtime);
++
++static void update_rq_clock_task(struct rq *rq, s64 delta)
++{
++ s64 irq_delta;
++
++ irq_delta = irq_time_read(cpu_of(rq)) - rq->prev_irq_time;
++
++ /*
++ * Since irq_time is only updated on {soft,}irq_exit, we might run into
++ * this case when a previous update_rq_clock() happened inside a
++ * {soft,}irq region.
++ *
++ * When this happens, we stop ->clock_task and only update the
++ * prev_irq_time stamp to account for the part that fit, so that a next
++ * update will consume the rest. This ensures ->clock_task is
++ * monotonic.
++ *
++ * It does however cause some slight miss-attribution of {soft,}irq
++ * time, a more accurate solution would be to update the irq_time using
++ * the current rq->clock timestamp, except that would require using
++ * atomic ops.
++ */
++ if (irq_delta > delta)
++ irq_delta = delta;
++
++ rq->prev_irq_time += irq_delta;
++ delta -= irq_delta;
++ rq->clock_task += delta;
++}
++
++#else /* CONFIG_IRQ_TIME_ACCOUNTING */
++
++static void update_rq_clock_task(struct rq *rq, s64 delta)
++{
++ rq->clock_task += delta;
++}
++
++#endif /* CONFIG_IRQ_TIME_ACCOUNTING */
++
++/*
++ * On each tick, see what percentage of that tick was attributed to each
++ * component and add the percentage to the _pc values. Once a _pc value has
++ * accumulated one tick's worth, account for that. This means the total
++ * percentage of load components will always be 100 per tick.
++ */
++static void pc_idle_time(struct rq *rq, unsigned long pc)
++{
++ struct cpu_usage_stat *cpustat = &kstat_this_cpu.cpustat;
++ cputime64_t tmp = cputime_to_cputime64(cputime_one_jiffy);
++
++ if (atomic_read(&rq->nr_iowait) > 0) {
++ rq->iowait_pc += pc;
++ if (rq->iowait_pc >= 100) {
++ rq->iowait_pc %= 100;
++ cpustat->iowait = cputime64_add(cpustat->iowait, tmp);
++ }
++ } else {
++ rq->idle_pc += pc;
++ if (rq->idle_pc >= 100) {
++ rq->idle_pc %= 100;
++ cpustat->idle = cputime64_add(cpustat->idle, tmp);
++ }
++ }
++}
++
++static void
++pc_system_time(struct rq *rq, struct task_struct *p, int hardirq_offset,
++ unsigned long pc, unsigned long ns)
++{
++ struct cpu_usage_stat *cpustat = &kstat_this_cpu.cpustat;
++ cputime_t one_jiffy_scaled = cputime_to_scaled(cputime_one_jiffy);
++ cputime64_t tmp = cputime_to_cputime64(cputime_one_jiffy);
++
++ p->stime_pc += pc;
++ if (p->stime_pc >= 100) {
++ p->stime_pc -= 100;
++ p->stime = cputime_add(p->stime, cputime_one_jiffy);
++ p->stimescaled = cputime_add(p->stimescaled, one_jiffy_scaled);
++ account_group_system_time(p, cputime_one_jiffy);
++ acct_update_integrals(p);
++ }
++ p->sched_time += ns;
++
++ if (hardirq_count() - hardirq_offset) {
++ rq->irq_pc += pc;
++ if (rq->irq_pc >= 100) {
++ rq->irq_pc %= 100;
++ cpustat->irq = cputime64_add(cpustat->irq, tmp);
++ }
++ } else if (in_serving_softirq()) {
++ rq->softirq_pc += pc;
++ if (rq->softirq_pc >= 100) {
++ rq->softirq_pc %= 100;
++ cpustat->softirq = cputime64_add(cpustat->softirq, tmp);
++ }
++ } else {
++ rq->system_pc += pc;
++ if (rq->system_pc >= 100) {
++ rq->system_pc %= 100;
++ cpustat->system = cputime64_add(cpustat->system, tmp);
++ }
++ }
++}
++
++static void pc_user_time(struct rq *rq, struct task_struct *p,
++ unsigned long pc, unsigned long ns)
++{
++ struct cpu_usage_stat *cpustat = &kstat_this_cpu.cpustat;
++ cputime_t one_jiffy_scaled = cputime_to_scaled(cputime_one_jiffy);
++ cputime64_t tmp = cputime_to_cputime64(cputime_one_jiffy);
++
++ p->utime_pc += pc;
++ if (p->utime_pc >= 100) {
++ p->utime_pc -= 100;
++ p->utime = cputime_add(p->utime, cputime_one_jiffy);
++ p->utimescaled = cputime_add(p->utimescaled, one_jiffy_scaled);
++ account_group_user_time(p, cputime_one_jiffy);
++ acct_update_integrals(p);
++ }
++ p->sched_time += ns;
++
++ if (TASK_NICE(p) > 0 || idleprio_task(p)) {
++ rq->nice_pc += pc;
++ if (rq->nice_pc >= 100) {
++ rq->nice_pc %= 100;
++ cpustat->nice = cputime64_add(cpustat->nice, tmp);
++ }
++ } else {
++ rq->user_pc += pc;
++ if (rq->user_pc >= 100) {
++ rq->user_pc %= 100;
++ cpustat->user = cputime64_add(cpustat->user, tmp);
++ }
++ }
++}
++
++/* Convert nanoseconds to percentage of one tick. */
++#define NS_TO_PC(NS) (NS * 100 / JIFFY_NS)
++
++/*
++ * This is called on clock ticks and on context switches.
++ * Bank in p->sched_time the ns elapsed since the last tick or switch.
++ * CPU scheduler quota accounting is also performed here in microseconds.
++ */
++static void
++update_cpu_clock(struct rq *rq, struct task_struct *p, int tick)
++{
++ long account_ns = rq->clock - rq->timekeep_clock;
++ struct task_struct *idle = rq->idle;
++ unsigned long account_pc;
++
++ if (unlikely(account_ns < 0))
++ account_ns = 0;
++
++ account_pc = NS_TO_PC(account_ns);
++
++ if (tick) {
++ int user_tick = user_mode(get_irq_regs());
++
++ /* Accurate tick timekeeping */
++ if (user_tick)
++ pc_user_time(rq, p, account_pc, account_ns);
++ else if (p != idle || (irq_count() != HARDIRQ_OFFSET))
++ pc_system_time(rq, p, HARDIRQ_OFFSET,
++ account_pc, account_ns);
++ else
++ pc_idle_time(rq, account_pc);
++ } else {
++ /* Accurate subtick timekeeping */
++ if (p == idle)
++ pc_idle_time(rq, account_pc);
++ else
++ pc_user_time(rq, p, account_pc, account_ns);
++ }
++
++ /* time_slice accounting is done in usecs to avoid overflow on 32bit */
++ if (rq->rq_policy != SCHED_FIFO && p != idle) {
++ s64 time_diff = rq->clock - rq->rq_last_ran;
++
++ niffy_diff(&time_diff, 1);
++ rq->rq_time_slice -= NS_TO_US(time_diff);
++ }
++ rq->rq_last_ran = rq->timekeep_clock = rq->clock;
++}
++
++/*
++ * Return any ns on the sched_clock that have not yet been accounted in
++ * @p in case that task is currently running.
++ *
++ * Called with task_grq_lock() held.
++ */
++static u64 do_task_delta_exec(struct task_struct *p, struct rq *rq)
++{
++ u64 ns = 0;
++
++ if (p == rq->curr) {
++ update_clocks(rq);
++ ns = rq->clock_task - rq->rq_last_ran;
++ if (unlikely((s64)ns < 0))
++ ns = 0;
++ }
++
++ return ns;
++}
++
++unsigned long long task_delta_exec(struct task_struct *p)
++{
++ unsigned long flags;
++ struct rq *rq;
++ u64 ns;
++
++ rq = task_grq_lock(p, &flags);
++ ns = do_task_delta_exec(p, rq);
++ task_grq_unlock(&flags);
++
++ return ns;
++}
++
++/*
++ * Return accounted runtime for the task.
++ * In case the task is currently running, return the runtime plus current's
++ * pending runtime that have not been accounted yet.
++ */
++unsigned long long task_sched_runtime(struct task_struct *p)
++{
++ unsigned long flags;
++ struct rq *rq;
++ u64 ns;
++
++ rq = task_grq_lock(p, &flags);
++ ns = p->sched_time + do_task_delta_exec(p, rq);
++ task_grq_unlock(&flags);
++
++ return ns;
++}
++
++/*
++ * Return sum_exec_runtime for the thread group.
++ * In case the task is currently running, return the sum plus current's
++ * pending runtime that have not been accounted yet.
++ *
++ * Note that the thread group might have other running tasks as well,
++ * so the return value not includes other pending runtime that other
++ * running tasks might have.
++ */
++unsigned long long thread_group_sched_runtime(struct task_struct *p)
++{
++ struct task_cputime totals;
++ unsigned long flags;
++ struct rq *rq;
++ u64 ns;
++
++ rq = task_grq_lock(p, &flags);
++ thread_group_cputime(p, &totals);
++ ns = totals.sum_exec_runtime + do_task_delta_exec(p, rq);
++ task_grq_unlock(&flags);
++
++ return ns;
++}
++
++/* Compatibility crap for removal */
++void account_user_time(struct task_struct *p, cputime_t cputime,
++ cputime_t cputime_scaled)
++{
++}
++
++void account_idle_time(cputime_t cputime)
++{
++}
++
++/*
++ * Account guest cpu time to a process.
++ * @p: the process that the cpu time gets accounted to
++ * @cputime: the cpu time spent in virtual machine since the last update
++ * @cputime_scaled: cputime scaled by cpu frequency
++ */
++static void account_guest_time(struct task_struct *p, cputime_t cputime,
++ cputime_t cputime_scaled)
++{
++ cputime64_t tmp;
++ struct cpu_usage_stat *cpustat = &kstat_this_cpu.cpustat;
++
++ tmp = cputime_to_cputime64(cputime);
++
++ /* Add guest time to process. */
++ p->utime = cputime_add(p->utime, cputime);
++ p->utimescaled = cputime_add(p->utimescaled, cputime_scaled);
++ account_group_user_time(p, cputime);
++ p->gtime = cputime_add(p->gtime, cputime);
++
++ /* Add guest time to cpustat. */
++ if (TASK_NICE(p) > 0) {
++ cpustat->nice = cputime64_add(cpustat->nice, tmp);
++ cpustat->guest_nice = cputime64_add(cpustat->guest_nice, tmp);
++ } else {
++ cpustat->user = cputime64_add(cpustat->user, tmp);
++ cpustat->guest = cputime64_add(cpustat->guest, tmp);
++ }
++}
++
++/*
++ * Account system cpu time to a process.
++ * @p: the process that the cpu time gets accounted to
++ * @hardirq_offset: the offset to subtract from hardirq_count()
++ * @cputime: the cpu time spent in kernel space since the last update
++ * @cputime_scaled: cputime scaled by cpu frequency
++ * This is for guest only now.
++ */
++void account_system_time(struct task_struct *p, int hardirq_offset,
++ cputime_t cputime, cputime_t cputime_scaled)
++{
++
++ if ((p->flags & PF_VCPU) && (irq_count() - hardirq_offset == 0))
++ account_guest_time(p, cputime, cputime_scaled);
++}
++
++/*
++ * Account for involuntary wait time.
++ * @steal: the cpu time spent in involuntary wait
++ */
++void account_steal_time(cputime_t cputime)
++{
++ struct cpu_usage_stat *cpustat = &kstat_this_cpu.cpustat;
++ cputime64_t cputime64 = cputime_to_cputime64(cputime);
++
++ cpustat->steal = cputime64_add(cpustat->steal, cputime64);
++}
++
++/*
++ * Account for idle time.
++ * @cputime: the cpu time spent in idle wait
++ */
++static void account_idle_times(cputime_t cputime)
++{
++ struct cpu_usage_stat *cpustat = &kstat_this_cpu.cpustat;
++ cputime64_t cputime64 = cputime_to_cputime64(cputime);
++ struct rq *rq = this_rq();
++
++ if (atomic_read(&rq->nr_iowait) > 0)
++ cpustat->iowait = cputime64_add(cpustat->iowait, cputime64);
++ else
++ cpustat->idle = cputime64_add(cpustat->idle, cputime64);
++}
++
++#ifndef CONFIG_VIRT_CPU_ACCOUNTING
++
++void account_process_tick(struct task_struct *p, int user_tick)
++{
++}
++
++/*
++ * Account multiple ticks of steal time.
++ * @p: the process from which the cpu time has been stolen
++ * @ticks: number of stolen ticks
++ */
++void account_steal_ticks(unsigned long ticks)
++{
++ account_steal_time(jiffies_to_cputime(ticks));
++}
++
++/*
++ * Account multiple ticks of idle time.
++ * @ticks: number of stolen ticks
++ */
++void account_idle_ticks(unsigned long ticks)
++{
++ account_idle_times(jiffies_to_cputime(ticks));
++}
++#endif
++
++static inline void grq_iso_lock(void)
++ __acquires(grq.iso_lock)
++{
++ raw_spin_lock(&grq.iso_lock);
++}
++
++static inline void grq_iso_unlock(void)
++ __releases(grq.iso_lock)
++{
++ raw_spin_unlock(&grq.iso_lock);
++}
++
++/*
++ * Functions to test for when SCHED_ISO tasks have used their allocated
++ * quota as real time scheduling and convert them back to SCHED_NORMAL.
++ * Where possible, the data is tested lockless, to avoid grabbing iso_lock
++ * because the occasional inaccurate result won't matter. However the
++ * tick data is only ever modified under lock. iso_refractory is only simply
++ * set to 0 or 1 so it's not worth grabbing the lock yet again for that.
++ */
++static void set_iso_refractory(void)
++{
++ grq.iso_refractory = 1;
++}
++
++static void clear_iso_refractory(void)
++{
++ grq.iso_refractory = 0;
++}
++
++/*
++ * Test if SCHED_ISO tasks have run longer than their alloted period as RT
++ * tasks and set the refractory flag if necessary. There is 10% hysteresis
++ * for unsetting the flag. 115/128 is ~90/100 as a fast shift instead of a
++ * slow division.
++ */
++static unsigned int test_ret_isorefractory(struct rq *rq)
++{
++ if (likely(!grq.iso_refractory)) {
++ if (grq.iso_ticks > ISO_PERIOD * sched_iso_cpu)
++ set_iso_refractory();
++ } else {
++ if (grq.iso_ticks < ISO_PERIOD * (sched_iso_cpu * 115 / 128))
++ clear_iso_refractory();
++ }
++ return grq.iso_refractory;
++}
++
++static void iso_tick(void)
++{
++ grq_iso_lock();
++ grq.iso_ticks += 100;
++ grq_iso_unlock();
++}
++
++/* No SCHED_ISO task was running so decrease rq->iso_ticks */
++static inline void no_iso_tick(void)
++{
++ if (grq.iso_ticks) {
++ grq_iso_lock();
++ grq.iso_ticks -= grq.iso_ticks / ISO_PERIOD + 1;
++ if (unlikely(grq.iso_refractory && grq.iso_ticks <
++ ISO_PERIOD * (sched_iso_cpu * 115 / 128)))
++ clear_iso_refractory();
++ grq_iso_unlock();
++ }
++}
++
++static int rq_running_iso(struct rq *rq)
++{
++ return rq->rq_prio == ISO_PRIO;
++}
++
++/* This manages tasks that have run out of timeslice during a scheduler_tick */
++static void task_running_tick(struct rq *rq)
++{
++ struct task_struct *p;
++
++ /*
++ * If a SCHED_ISO task is running we increment the iso_ticks. In
++ * order to prevent SCHED_ISO tasks from causing starvation in the
++ * presence of true RT tasks we account those as iso_ticks as well.
++ */
++ if ((rt_queue(rq) || (iso_queue(rq) && !grq.iso_refractory))) {
++ if (grq.iso_ticks <= (ISO_PERIOD * 100) - 100)
++ iso_tick();
++ } else
++ no_iso_tick();
++
++ if (iso_queue(rq)) {
++ if (unlikely(test_ret_isorefractory(rq))) {
++ if (rq_running_iso(rq)) {
++ /*
++ * SCHED_ISO task is running as RT and limit
++ * has been hit. Force it to reschedule as
++ * SCHED_NORMAL by zeroing its time_slice
++ */
++ rq->rq_time_slice = 0;
++ }
++ }
++ }
++
++ /* SCHED_FIFO tasks never run out of timeslice. */
++ if (rq->rq_policy == SCHED_FIFO)
++ return;
++ /*
++ * Tasks that were scheduled in the first half of a tick are not
++ * allowed to run into the 2nd half of the next tick if they will
++ * run out of time slice in the interim. Otherwise, if they have
++ * less than RESCHED_US μs of time slice left they will be rescheduled.
++ */
++ if (rq->dither) {
++ if (rq->rq_time_slice > HALF_JIFFY_US)
++ return;
++ else
++ rq->rq_time_slice = 0;
++ } else if (rq->rq_time_slice >= RESCHED_US)
++ return;
++
++ /* p->time_slice < RESCHED_US. We only modify task_struct under grq lock */
++ p = rq->curr;
++ requeue_task(p);
++ grq_lock();
++ set_tsk_need_resched(p);
++ grq_unlock();
++}
++
++void wake_up_idle_cpu(int cpu);
++
++/*
++ * This function gets called by the timer code, with HZ frequency.
++ * We call it with interrupts disabled. The data modified is all
++ * local to struct rq so we don't need to grab grq lock.
++ */
++void scheduler_tick(void)
++{
++ int cpu __maybe_unused = smp_processor_id();
++ struct rq *rq = cpu_rq(cpu);
++
++ sched_clock_tick();
++ /* grq lock not grabbed, so only update rq clock */
++ update_rq_clock(rq);
++ update_cpu_clock(rq, rq->curr, 1);
++ if (!rq_idle(rq))
++ task_running_tick(rq);
++ else
++ no_iso_tick();
++ rq->last_tick = rq->clock;
++ perf_event_task_tick();
++}
++
++notrace unsigned long get_parent_ip(unsigned long addr)
++{
++ if (in_lock_functions(addr)) {
++ addr = CALLER_ADDR2;
++ if (in_lock_functions(addr))
++ addr = CALLER_ADDR3;
++ }
++ return addr;
++}
++
++#if defined(CONFIG_PREEMPT) && (defined(CONFIG_DEBUG_PREEMPT) || \
++ defined(CONFIG_PREEMPT_TRACER))
++void __kprobes add_preempt_count(int val)
++{
++#ifdef CONFIG_DEBUG_PREEMPT
++ /*
++ * Underflow?
++ */
++ if (DEBUG_LOCKS_WARN_ON((preempt_count() < 0)))
++ return;
++#endif
++ preempt_count() += val;
++#ifdef CONFIG_DEBUG_PREEMPT
++ /*
++ * Spinlock count overflowing soon?
++ */
++ DEBUG_LOCKS_WARN_ON((preempt_count() & PREEMPT_MASK) >=
++ PREEMPT_MASK - 10);
++#endif
++ if (preempt_count() == val)
++ trace_preempt_off(CALLER_ADDR0, get_parent_ip(CALLER_ADDR1));
++}
++EXPORT_SYMBOL(add_preempt_count);
++
++void __kprobes sub_preempt_count(int val)
++{
++#ifdef CONFIG_DEBUG_PREEMPT
++ /*
++ * Underflow?
++ */
++ if (DEBUG_LOCKS_WARN_ON(val > preempt_count()))
++ return;
++ /*
++ * Is the spinlock portion underflowing?
++ */
++ if (DEBUG_LOCKS_WARN_ON((val < PREEMPT_MASK) &&
++ !(preempt_count() & PREEMPT_MASK)))
++ return;
++#endif
++
++ if (preempt_count() == val)
++ trace_preempt_on(CALLER_ADDR0, get_parent_ip(CALLER_ADDR1));
++ preempt_count() -= val;
++}
++EXPORT_SYMBOL(sub_preempt_count);
++#endif
++
++/*
++ * Deadline is "now" in niffies + (offset by priority). Setting the deadline
++ * is the key to everything. It distributes cpu fairly amongst tasks of the
++ * same nice value, it proportions cpu according to nice level, it means the
++ * task that last woke up the longest ago has the earliest deadline, thus
++ * ensuring that interactive tasks get low latency on wake up. The CPU
++ * proportion works out to the square of the virtual deadline difference, so
++ * this equation will give nice 19 3% CPU compared to nice 0.
++ */
++static inline u64 prio_deadline_diff(int user_prio)
++{
++ return (prio_ratios[user_prio] * rr_interval * (MS_TO_NS(1) / 128));
++}
++
++static inline u64 task_deadline_diff(struct task_struct *p)
++{
++ return prio_deadline_diff(TASK_USER_PRIO(p));
++}
++
++static inline u64 static_deadline_diff(int static_prio)
++{
++ return prio_deadline_diff(USER_PRIO(static_prio));
++}
++
++static inline int ms_longest_deadline_diff(void)
++{
++ return NS_TO_MS(prio_deadline_diff(39));
++}
++
++/*
++ * The time_slice is only refilled when it is empty and that is when we set a
++ * new deadline.
++ */
++static void time_slice_expired(struct task_struct *p)
++{
++ p->time_slice = timeslice();
++ p->deadline = grq.niffies + task_deadline_diff(p);
++}
++
++/*
++ * Timeslices below RESCHED_US are considered as good as expired as there's no
++ * point rescheduling when there's so little time left. SCHED_BATCH tasks
++ * have been flagged be not latency sensitive and likely to be fully CPU
++ * bound so every time they're rescheduled they have their time_slice
++ * refilled, but get a new later deadline to have little effect on
++ * SCHED_NORMAL tasks.
++
++ */
++static inline void check_deadline(struct task_struct *p)
++{
++ if (p->time_slice < RESCHED_US || batch_task(p))
++ time_slice_expired(p);
++}
++
++/*
++ * O(n) lookup of all tasks in the global runqueue. The real brainfuck
++ * of lock contention and O(n). It's not really O(n) as only the queued,
++ * but not running tasks are scanned, and is O(n) queued in the worst case
++ * scenario only because the right task can be found before scanning all of
++ * them.
++ * Tasks are selected in this order:
++ * Real time tasks are selected purely by their static priority and in the
++ * order they were queued, so the lowest value idx, and the first queued task
++ * of that priority value is chosen.
++ * If no real time tasks are found, the SCHED_ISO priority is checked, and
++ * all SCHED_ISO tasks have the same priority value, so they're selected by
++ * the earliest deadline value.
++ * If no SCHED_ISO tasks are found, SCHED_NORMAL tasks are selected by the
++ * earliest deadline.
++ * Finally if no SCHED_NORMAL tasks are found, SCHED_IDLEPRIO tasks are
++ * selected by the earliest deadline.
++ */
++static inline struct
++task_struct *earliest_deadline_task(struct rq *rq, struct task_struct *idle)
++{
++ u64 dl, earliest_deadline = 0; /* Initialise to silence compiler */
++ struct task_struct *p, *edt = idle;
++ unsigned int cpu = cpu_of(rq);
++ struct list_head *queue;
++ int idx = 0;
++
++retry:
++ idx = find_next_bit(grq.prio_bitmap, PRIO_LIMIT, idx);
++ if (idx >= PRIO_LIMIT)
++ goto out;
++ queue = grq.queue + idx;
++ list_for_each_entry(p, queue, run_list) {
++ /* Make sure cpu affinity is ok */
++ if (needs_other_cpu(p, cpu))
++ continue;
++ if (idx < MAX_RT_PRIO) {
++ /* We found an rt task */
++ edt = p;
++ goto out_take;
++ }
++
++ dl = p->deadline + cache_distance(task_rq(p), rq, p);
++
++ /*
++ * No rt tasks. Find the earliest deadline task. Now we're in
++ * O(n) territory. This is what we silenced the compiler for:
++ * edt will always start as idle.
++ */
++ if (edt == idle ||
++ deadline_before(dl, earliest_deadline)) {
++ earliest_deadline = dl;
++ edt = p;
++ }
++ }
++ if (edt == idle) {
++ if (++idx < PRIO_LIMIT)
++ goto retry;
++ goto out;
++ }
++out_take:
++ take_task(rq, edt);
++out:
++ return edt;
++}
++
++/*
++ * Print scheduling while atomic bug:
++ */
++static noinline void __schedule_bug(struct task_struct *prev)
++{
++ struct pt_regs *regs = get_irq_regs();
++
++ printk(KERN_ERR "BUG: scheduling while atomic: %s/%d/0x%08x\n",
++ prev->comm, prev->pid, preempt_count());
++
++ debug_show_held_locks(prev);
++ print_modules();
++ if (irqs_disabled())
++ print_irqtrace_events(prev);
++
++ if (regs)
++ show_regs(regs);
++ else
++ dump_stack();
++}
++
++/*
++ * Various schedule()-time debugging checks and statistics:
++ */
++static inline void schedule_debug(struct task_struct *prev)
++{
++ /*
++ * Test if we are atomic. Since do_exit() needs to call into
++ * schedule() atomically, we ignore that path for now.
++ * Otherwise, whine if we are scheduling when we should not be.
++ */
++ if (unlikely(in_atomic_preempt_off() && !prev->exit_state))
++ __schedule_bug(prev);
++
++ profile_hit(SCHED_PROFILING, __builtin_return_address(0));
++
++ schedstat_inc(this_rq(), sched_count);
++#ifdef CONFIG_SCHEDSTATS
++ if (unlikely(prev->lock_depth >= 0)) {
++ schedstat_inc(this_rq(), bkl_count);
++ schedstat_inc(prev, sched_info.bkl_count);
++ }
++#endif
++}
++
++/*
++ * The currently running task's information is all stored in rq local data
++ * which is only modified by the local CPU, thereby allowing the data to be
++ * changed without grabbing the grq lock.
++ */
++static inline void set_rq_task(struct rq *rq, struct task_struct *p)
++{
++ rq->rq_time_slice = p->time_slice;
++ rq->rq_deadline = p->deadline;
++ rq->rq_last_ran = p->last_ran;
++ rq->rq_policy = p->policy;
++ rq->rq_prio = p->prio;
++ if (p != rq->idle)
++ rq->rq_running = 1;
++ else
++ rq->rq_running = 0;
++}
++
++static void reset_rq_task(struct rq *rq, struct task_struct *p)
++{
++ rq->rq_policy = p->policy;
++ rq->rq_prio = p->prio;
++}
++
++/*
++ * schedule() is the main scheduler function.
++ */
++asmlinkage void __sched schedule(void)
++{
++ struct task_struct *prev, *next, *idle;
++ unsigned long *switch_count;
++ int deactivate, cpu;
++ struct rq *rq;
++
++need_resched:
++ preempt_disable();
++
++ cpu = smp_processor_id();
++ rq = cpu_rq(cpu);
++ idle = rq->idle;
++ rcu_note_context_switch(cpu);
++ prev = rq->curr;
++
++ release_kernel_lock(prev);
++need_resched_nonpreemptible:
++
++ deactivate = 0;
++ schedule_debug(prev);
++
++ grq_lock_irq();
++ update_clocks(rq);
++ update_cpu_clock(rq, prev, 0);
++ if (rq->clock - rq->last_tick > HALF_JIFFY_NS)
++ rq->dither = 0;
++ else
++ rq->dither = 1;
++
++ clear_tsk_need_resched(prev);
++
++ switch_count = &prev->nivcsw;
++ if (prev->state && !(preempt_count() & PREEMPT_ACTIVE)) {
++ if (unlikely(signal_pending_state(prev->state, prev))) {
++ prev->state = TASK_RUNNING;
++ } else {
++ deactivate = 1;
++ /*
++ * If a worker is going to sleep, notify and
++ * ask workqueue whether it wants to wake up a
++ * task to maintain concurrency. If so, wake
++ * up the task.
++ */
++ if (prev->flags & PF_WQ_WORKER) {
++ struct task_struct *to_wakeup;
++
++ to_wakeup = wq_worker_sleeping(prev, cpu);
++ if (to_wakeup) {
++ /* This shouldn't happen, but does */
++ if (unlikely(to_wakeup == prev))
++ deactivate = 0;
++ else
++ try_to_wake_up_local(to_wakeup);
++ }
++ }
++ }
++ switch_count = &prev->nvcsw;
++ }
++
++ if (prev != idle) {
++ /* Update all the information stored on struct rq */
++ prev->time_slice = rq->rq_time_slice;
++ prev->deadline = rq->rq_deadline;
++ check_deadline(prev);
++ prev->last_ran = rq->clock;
++
++ /* Task changed affinity off this CPU */
++ if (needs_other_cpu(prev, cpu))
++ resched_suitable_idle(prev);
++ else if (!deactivate) {
++ if (!queued_notrunning()) {
++ /*
++ * We now know prev is the only thing that is
++ * awaiting CPU so we can bypass rechecking for
++ * the earliest deadline task and just run it
++ * again.
++ */
++ grq_unlock_irq();
++ goto rerun_prev_unlocked;
++ } else {
++ /*
++ * If prev got kicked off by a task that has to
++ * run on this CPU for affinity reasons then
++ * there may be an idle CPU it can go to.
++ */
++ resched_suitable_idle(prev);
++ }
++ }
++ return_task(prev, deactivate);
++ }
++
++ if (unlikely(!queued_notrunning())) {
++ /*
++ * This CPU is now truly idle as opposed to when idle is
++ * scheduled as a high priority task in its own right.
++ */
++ next = idle;
++ schedstat_inc(rq, sched_goidle);
++ set_cpuidle_map(cpu);
++ } else {
++ next = earliest_deadline_task(rq, idle);
++ prefetch(next);
++ prefetch_stack(next);
++ clear_cpuidle_map(cpu);
++ }
++
++ if (likely(prev != next)) {
++ sched_info_switch(prev, next);
++ perf_event_task_sched_out(prev, next);
++
++ set_rq_task(rq, next);
++ grq.nr_switches++;
++ prev->oncpu = 0;
++ next->oncpu = 1;
++ rq->curr = next;
++ ++*switch_count;
++
++ context_switch(rq, prev, next); /* unlocks the grq */
++ /*
++ * The context switch have flipped the stack from under us
++ * and restored the local variables which were saved when
++ * this task called schedule() in the past. prev == current
++ * is still correct, but it can be moved to another cpu/rq.
++ */
++ cpu = smp_processor_id();
++ rq = cpu_rq(cpu);
++ idle = rq->idle;
++ } else
++ grq_unlock_irq();
++
++rerun_prev_unlocked:
++ if (unlikely(reacquire_kernel_lock(prev)))
++ goto need_resched_nonpreemptible;
++
++ preempt_enable_no_resched();
++ if (need_resched())
++ goto need_resched;
++}
++EXPORT_SYMBOL(schedule);
++
++#ifdef CONFIG_SMP
++int mutex_spin_on_owner(struct mutex *lock, struct thread_info *owner)
++{
++ unsigned int cpu;
++ struct rq *rq;
++
++#ifdef CONFIG_DEBUG_PAGEALLOC
++ /*
++ * Need to access the cpu field knowing that
++ * DEBUG_PAGEALLOC could have unmapped it if
++ * the mutex owner just released it and exited.
++ */
++ if (probe_kernel_address(&owner->cpu, cpu))
++ return 0;
++#else
++ cpu = owner->cpu;
++#endif
++
++ /*
++ * Even if the access succeeded (likely case),
++ * the cpu field may no longer be valid.
++ */
++ if (cpu >= nr_cpumask_bits)
++ return 0;
++
++ /*
++ * We need to validate that we can do a
++ * get_cpu() and that we have the percpu area.
++ */
++ if (!cpu_online(cpu))
++ return 0;
++
++ rq = cpu_rq(cpu);
++
++ for (;;) {
++ /*
++ * Owner changed, break to re-assess state.
++ */
++ if (lock->owner != owner)
++ break;
++
++ /*
++ * Is that owner really running on that cpu?
++ */
++ if (task_thread_info(rq->curr) != owner || need_resched())
++ return 0;
++
++ cpu_relax();
++ }
++
++ return 1;
++}
++#endif
++
++#ifdef CONFIG_PREEMPT
++/*
++ * this is the entry point to schedule() from in-kernel preemption
++ * off of preempt_enable. Kernel preemptions off return from interrupt
++ * occur there and call schedule directly.
++ */
++asmlinkage void __sched notrace preempt_schedule(void)
++{
++ struct thread_info *ti = current_thread_info();
++
++ /*
++ * If there is a non-zero preempt_count or interrupts are disabled,
++ * we do not want to preempt the current task. Just return..
++ */
++ if (likely(ti->preempt_count || irqs_disabled()))
++ return;
++
++ do {
++ add_preempt_count_notrace(PREEMPT_ACTIVE);
++ schedule();
++ sub_preempt_count_notrace(PREEMPT_ACTIVE);
++
++ /*
++ * Check again in case we missed a preemption opportunity
++ * between schedule and now.
++ */
++ barrier();
++ } while (need_resched());
++}
++EXPORT_SYMBOL(preempt_schedule);
++
++/*
++ * this is the entry point to schedule() from kernel preemption
++ * off of irq context.
++ * Note, that this is called and return with irqs disabled. This will
++ * protect us against recursive calling from irq.
++ */
++asmlinkage void __sched preempt_schedule_irq(void)
++{
++ struct thread_info *ti = current_thread_info();
++
++ /* Catch callers which need to be fixed */
++ BUG_ON(ti->preempt_count || !irqs_disabled());
++
++ do {
++ add_preempt_count(PREEMPT_ACTIVE);
++ local_irq_enable();
++ schedule();
++ local_irq_disable();
++ sub_preempt_count(PREEMPT_ACTIVE);
++
++ /*
++ * Check again in case we missed a preemption opportunity
++ * between schedule and now.
++ */
++ barrier();
++ } while (need_resched());
++}
++
++#endif /* CONFIG_PREEMPT */
++
++int default_wake_function(wait_queue_t *curr, unsigned mode, int wake_flags,
++ void *key)
++{
++ return try_to_wake_up(curr->private, mode, wake_flags);
++}
++EXPORT_SYMBOL(default_wake_function);
++
++/*
++ * The core wakeup function. Non-exclusive wakeups (nr_exclusive == 0) just
++ * wake everything up. If it's an exclusive wakeup (nr_exclusive == small +ve
++ * number) then we wake all the non-exclusive tasks and one exclusive task.
++ *
++ * There are circumstances in which we can try to wake a task which has already
++ * started to run but is not in state TASK_RUNNING. try_to_wake_up() returns
++ * zero in this (rare) case, and we handle it by continuing to scan the queue.
++ */
++static void __wake_up_common(wait_queue_head_t *q, unsigned int mode,
++ int nr_exclusive, int wake_flags, void *key)
++{
++ struct list_head *tmp, *next;
++
++ list_for_each_safe(tmp, next, &q->task_list) {
++ wait_queue_t *curr = list_entry(tmp, wait_queue_t, task_list);
++ unsigned int flags = curr->flags;
++
++ if (curr->func(curr, mode, wake_flags, key) &&
++ (flags & WQ_FLAG_EXCLUSIVE) && !--nr_exclusive)
++ break;
++ }
++}
++
++/**
++ * __wake_up - wake up threads blocked on a waitqueue.
++ * @q: the waitqueue
++ * @mode: which threads
++ * @nr_exclusive: how many wake-one or wake-many threads to wake up
++ * @key: is directly passed to the wakeup function
++ *
++ * It may be assumed that this function implies a write memory barrier before
++ * changing the task state if and only if any tasks are woken up.
++ */
++void __wake_up(wait_queue_head_t *q, unsigned int mode,
++ int nr_exclusive, void *key)
++{
++ unsigned long flags;
++
++ spin_lock_irqsave(&q->lock, flags);
++ __wake_up_common(q, mode, nr_exclusive, 0, key);
++ spin_unlock_irqrestore(&q->lock, flags);
++}
++EXPORT_SYMBOL(__wake_up);
++
++/*
++ * Same as __wake_up but called with the spinlock in wait_queue_head_t held.
++ */
++void __wake_up_locked(wait_queue_head_t *q, unsigned int mode)
++{
++ __wake_up_common(q, mode, 1, 0, NULL);
++}
++EXPORT_SYMBOL_GPL(__wake_up_locked);
++
++void __wake_up_locked_key(wait_queue_head_t *q, unsigned int mode, void *key)
++{
++ __wake_up_common(q, mode, 1, 0, key);
++}
++
++/**
++ * __wake_up_sync_key - wake up threads blocked on a waitqueue.
++ * @q: the waitqueue
++ * @mode: which threads
++ * @nr_exclusive: how many wake-one or wake-many threads to wake up
++ * @key: opaque value to be passed to wakeup targets
++ *
++ * The sync wakeup differs that the waker knows that it will schedule
++ * away soon, so while the target thread will be woken up, it will not
++ * be migrated to another CPU - ie. the two threads are 'synchronised'
++ * with each other. This can prevent needless bouncing between CPUs.
++ *
++ * On UP it can prevent extra preemption.
++ *
++ * It may be assumed that this function implies a write memory barrier before
++ * changing the task state if and only if any tasks are woken up.
++ */
++void __wake_up_sync_key(wait_queue_head_t *q, unsigned int mode,
++ int nr_exclusive, void *key)
++{
++ unsigned long flags;
++ int wake_flags = WF_SYNC;
++
++ if (unlikely(!q))
++ return;
++
++ if (unlikely(!nr_exclusive))
++ wake_flags = 0;
++
++ spin_lock_irqsave(&q->lock, flags);
++ __wake_up_common(q, mode, nr_exclusive, wake_flags, key);
++ spin_unlock_irqrestore(&q->lock, flags);
++}
++EXPORT_SYMBOL_GPL(__wake_up_sync_key);
++
++/**
++ * __wake_up_sync - wake up threads blocked on a waitqueue.
++ * @q: the waitqueue
++ * @mode: which threads
++ * @nr_exclusive: how many wake-one or wake-many threads to wake up
++ *
++ * The sync wakeup differs that the waker knows that it will schedule
++ * away soon, so while the target thread will be woken up, it will not
++ * be migrated to another CPU - ie. the two threads are 'synchronised'
++ * with each other. This can prevent needless bouncing between CPUs.
++ *
++ * On UP it can prevent extra preemption.
++ */
++void __wake_up_sync(wait_queue_head_t *q, unsigned int mode, int nr_exclusive)
++{
++ unsigned long flags;
++ int sync = 1;
++
++ if (unlikely(!q))
++ return;
++
++ if (unlikely(!nr_exclusive))
++ sync = 0;
++
++ spin_lock_irqsave(&q->lock, flags);
++ __wake_up_common(q, mode, nr_exclusive, sync, NULL);
++ spin_unlock_irqrestore(&q->lock, flags);
++}
++EXPORT_SYMBOL_GPL(__wake_up_sync); /* For internal use only */
++
++/**
++ * complete: - signals a single thread waiting on this completion
++ * @x: holds the state of this particular completion
++ *
++ * This will wake up a single thread waiting on this completion. Threads will be
++ * awakened in the same order in which they were queued.
++ *
++ * See also complete_all(), wait_for_completion() and related routines.
++ *
++ * It may be assumed that this function implies a write memory barrier before
++ * changing the task state if and only if any tasks are woken up.
++ */
++void complete(struct completion *x)
++{
++ unsigned long flags;
++
++ spin_lock_irqsave(&x->wait.lock, flags);
++ x->done++;
++ __wake_up_common(&x->wait, TASK_NORMAL, 1, 0, NULL);
++ spin_unlock_irqrestore(&x->wait.lock, flags);
++}
++EXPORT_SYMBOL(complete);
++
++/**
++ * complete_all: - signals all threads waiting on this completion
++ * @x: holds the state of this particular completion
++ *
++ * This will wake up all threads waiting on this particular completion event.
++ *
++ * It may be assumed that this function implies a write memory barrier before
++ * changing the task state if and only if any tasks are woken up.
++ */
++void complete_all(struct completion *x)
++{
++ unsigned long flags;
++
++ spin_lock_irqsave(&x->wait.lock, flags);
++ x->done += UINT_MAX/2;
++ __wake_up_common(&x->wait, TASK_NORMAL, 0, 0, NULL);
++ spin_unlock_irqrestore(&x->wait.lock, flags);
++}
++EXPORT_SYMBOL(complete_all);
++
++static inline long __sched
++do_wait_for_common(struct completion *x, long timeout, int state)
++{
++ if (!x->done) {
++ DECLARE_WAITQUEUE(wait, current);
++
++ __add_wait_queue_tail_exclusive(&x->wait, &wait);
++ do {
++ if (signal_pending_state(state, current)) {
++ timeout = -ERESTARTSYS;
++ break;
++ }
++ __set_current_state(state);
++ spin_unlock_irq(&x->wait.lock);
++ timeout = schedule_timeout(timeout);
++ spin_lock_irq(&x->wait.lock);
++ } while (!x->done && timeout);
++ __remove_wait_queue(&x->wait, &wait);
++ if (!x->done)
++ return timeout;
++ }
++ x->done--;
++ return timeout ?: 1;
++}
++
++static long __sched
++wait_for_common(struct completion *x, long timeout, int state)
++{
++ might_sleep();
++
++ spin_lock_irq(&x->wait.lock);
++ timeout = do_wait_for_common(x, timeout, state);
++ spin_unlock_irq(&x->wait.lock);
++ return timeout;
++}
++
++/**
++ * wait_for_completion: - waits for completion of a task
++ * @x: holds the state of this particular completion
++ *
++ * This waits to be signaled for completion of a specific task. It is NOT
++ * interruptible and there is no timeout.
++ *
++ * See also similar routines (i.e. wait_for_completion_timeout()) with timeout
++ * and interrupt capability. Also see complete().
++ */
++void __sched wait_for_completion(struct completion *x)
++{
++ wait_for_common(x, MAX_SCHEDULE_TIMEOUT, TASK_UNINTERRUPTIBLE);
++}
++EXPORT_SYMBOL(wait_for_completion);
++
++/**
++ * wait_for_completion_timeout: - waits for completion of a task (w/timeout)
++ * @x: holds the state of this particular completion
++ * @timeout: timeout value in jiffies
++ *
++ * This waits for either a completion of a specific task to be signaled or for a
++ * specified timeout to expire. The timeout is in jiffies. It is not
++ * interruptible.
++ */
++unsigned long __sched
++wait_for_completion_timeout(struct completion *x, unsigned long timeout)
++{
++ return wait_for_common(x, timeout, TASK_UNINTERRUPTIBLE);
++}
++EXPORT_SYMBOL(wait_for_completion_timeout);
++
++/**
++ * wait_for_completion_interruptible: - waits for completion of a task (w/intr)
++ * @x: holds the state of this particular completion
++ *
++ * This waits for completion of a specific task to be signaled. It is
++ * interruptible.
++ */
++int __sched wait_for_completion_interruptible(struct completion *x)
++{
++ long t = wait_for_common(x, MAX_SCHEDULE_TIMEOUT, TASK_INTERRUPTIBLE);
++ if (t == -ERESTARTSYS)
++ return t;
++ return 0;
++}
++EXPORT_SYMBOL(wait_for_completion_interruptible);
++
++/**
++ * wait_for_completion_interruptible_timeout: - waits for completion (w/(to,intr))
++ * @x: holds the state of this particular completion
++ * @timeout: timeout value in jiffies
++ *
++ * This waits for either a completion of a specific task to be signaled or for a
++ * specified timeout to expire. It is interruptible. The timeout is in jiffies.
++ */
++unsigned long __sched
++wait_for_completion_interruptible_timeout(struct completion *x,
++ unsigned long timeout)
++{
++ return wait_for_common(x, timeout, TASK_INTERRUPTIBLE);
++}
++EXPORT_SYMBOL(wait_for_completion_interruptible_timeout);
++
++/**
++ * wait_for_completion_killable: - waits for completion of a task (killable)
++ * @x: holds the state of this particular completion
++ *
++ * This waits to be signaled for completion of a specific task. It can be
++ * interrupted by a kill signal.
++ */
++int __sched wait_for_completion_killable(struct completion *x)
++{
++ long t = wait_for_common(x, MAX_SCHEDULE_TIMEOUT, TASK_KILLABLE);
++ if (t == -ERESTARTSYS)
++ return t;
++ return 0;
++}
++EXPORT_SYMBOL(wait_for_completion_killable);
++
++/**
++ * wait_for_completion_killable_timeout: - waits for completion of a task (w/(to,killable))
++ * @x: holds the state of this particular completion
++ * @timeout: timeout value in jiffies
++ *
++ * This waits for either a completion of a specific task to be
++ * signaled or for a specified timeout to expire. It can be
++ * interrupted by a kill signal. The timeout is in jiffies.
++ */
++unsigned long __sched
++wait_for_completion_killable_timeout(struct completion *x,
++ unsigned long timeout)
++{
++ return wait_for_common(x, timeout, TASK_KILLABLE);
++}
++EXPORT_SYMBOL(wait_for_completion_killable_timeout);
++
++/**
++ * try_wait_for_completion - try to decrement a completion without blocking
++ * @x: completion structure
++ *
++ * Returns: 0 if a decrement cannot be done without blocking
++ * 1 if a decrement succeeded.
++ *
++ * If a completion is being used as a counting completion,
++ * attempt to decrement the counter without blocking. This
++ * enables us to avoid waiting if the resource the completion
++ * is protecting is not available.
++ */
++bool try_wait_for_completion(struct completion *x)
++{
++ unsigned long flags;
++ int ret = 1;
++
++ spin_lock_irqsave(&x->wait.lock, flags);
++ if (!x->done)
++ ret = 0;
++ else
++ x->done--;
++ spin_unlock_irqrestore(&x->wait.lock, flags);
++ return ret;
++}
++EXPORT_SYMBOL(try_wait_for_completion);
++
++/**
++ * completion_done - Test to see if a completion has any waiters
++ * @x: completion structure
++ *
++ * Returns: 0 if there are waiters (wait_for_completion() in progress)
++ * 1 if there are no waiters.
++ *
++ */
++bool completion_done(struct completion *x)
++{
++ unsigned long flags;
++ int ret = 1;
++
++ spin_lock_irqsave(&x->wait.lock, flags);
++ if (!x->done)
++ ret = 0;
++ spin_unlock_irqrestore(&x->wait.lock, flags);
++ return ret;
++}
++EXPORT_SYMBOL(completion_done);
++
++static long __sched
++sleep_on_common(wait_queue_head_t *q, int state, long timeout)
++{
++ unsigned long flags;
++ wait_queue_t wait;
++
++ init_waitqueue_entry(&wait, current);
++
++ __set_current_state(state);
++
++ spin_lock_irqsave(&q->lock, flags);
++ __add_wait_queue(q, &wait);
++ spin_unlock(&q->lock);
++ timeout = schedule_timeout(timeout);
++ spin_lock_irq(&q->lock);
++ __remove_wait_queue(q, &wait);
++ spin_unlock_irqrestore(&q->lock, flags);
++
++ return timeout;
++}
++
++void __sched interruptible_sleep_on(wait_queue_head_t *q)
++{
++ sleep_on_common(q, TASK_INTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT);
++}
++EXPORT_SYMBOL(interruptible_sleep_on);
++
++long __sched
++interruptible_sleep_on_timeout(wait_queue_head_t *q, long timeout)
++{
++ return sleep_on_common(q, TASK_INTERRUPTIBLE, timeout);
++}
++EXPORT_SYMBOL(interruptible_sleep_on_timeout);
++
++void __sched sleep_on(wait_queue_head_t *q)
++{
++ sleep_on_common(q, TASK_UNINTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT);
++}
++EXPORT_SYMBOL(sleep_on);
++
++long __sched sleep_on_timeout(wait_queue_head_t *q, long timeout)
++{
++ return sleep_on_common(q, TASK_UNINTERRUPTIBLE, timeout);
++}
++EXPORT_SYMBOL(sleep_on_timeout);
++
++#ifdef CONFIG_RT_MUTEXES
++
++/*
++ * rt_mutex_setprio - set the current priority of a task
++ * @p: task
++ * @prio: prio value (kernel-internal form)
++ *
++ * This function changes the 'effective' priority of a task. It does
++ * not touch ->normal_prio like __setscheduler().
++ *
++ * Used by the rt_mutex code to implement priority inheritance logic.
++ */
++void rt_mutex_setprio(struct task_struct *p, int prio)
++{
++ unsigned long flags;
++ int queued, oldprio;
++ struct rq *rq;
++
++ BUG_ON(prio < 0 || prio > MAX_PRIO);
++
++ rq = task_grq_lock(p, &flags);
++
++ trace_sched_pi_setprio(p, prio);
++ oldprio = p->prio;
++ queued = task_queued(p);
++ if (queued)
++ dequeue_task(p);
++ p->prio = prio;
++ if (task_running(p) && prio > oldprio)
++ resched_task(p);
++ if (queued) {
++ enqueue_task(p);
++ try_preempt(p, rq);
++ }
++
++ task_grq_unlock(&flags);
++}
++
++#endif
++
++/*
++ * Adjust the deadline for when the priority is to change, before it's
++ * changed.
++ */
++static inline void adjust_deadline(struct task_struct *p, int new_prio)
++{
++ p->deadline += static_deadline_diff(new_prio) - task_deadline_diff(p);
++}
++
++void set_user_nice(struct task_struct *p, long nice)
++{
++ int queued, new_static, old_static;
++ unsigned long flags;
++ struct rq *rq;
++
++ if (TASK_NICE(p) == nice || nice < -20 || nice > 19)
++ return;
++ new_static = NICE_TO_PRIO(nice);
++ /*
++ * We have to be careful, if called from sys_setpriority(),
++ * the task might be in the middle of scheduling on another CPU.
++ */
++ rq = time_task_grq_lock(p, &flags);
++ /*
++ * The RT priorities are set via sched_setscheduler(), but we still
++ * allow the 'normal' nice value to be set - but as expected
++ * it wont have any effect on scheduling until the task is
++ * not SCHED_NORMAL/SCHED_BATCH:
++ */
++ if (has_rt_policy(p)) {
++ p->static_prio = new_static;
++ goto out_unlock;
++ }
++ queued = task_queued(p);
++ if (queued)
++ dequeue_task(p);
++
++ adjust_deadline(p, new_static);
++ old_static = p->static_prio;
++ p->static_prio = new_static;
++ p->prio = effective_prio(p);
++
++ if (queued) {
++ enqueue_task(p);
++ if (new_static < old_static)
++ try_preempt(p, rq);
++ } else if (task_running(p)) {
++ reset_rq_task(rq, p);
++ if (old_static < new_static)
++ resched_task(p);
++ }
++out_unlock:
++ task_grq_unlock(&flags);
++}
++EXPORT_SYMBOL(set_user_nice);
++
++/*
++ * can_nice - check if a task can reduce its nice value
++ * @p: task
++ * @nice: nice value
++ */
++int can_nice(const struct task_struct *p, const int nice)
++{
++ /* convert nice value [19,-20] to rlimit style value [1,40] */
++ int nice_rlim = 20 - nice;
++
++ return (nice_rlim <= task_rlimit(p, RLIMIT_NICE) ||
++ capable(CAP_SYS_NICE));
++}
++
++#ifdef __ARCH_WANT_SYS_NICE
++
++/*
++ * sys_nice - change the priority of the current process.
++ * @increment: priority increment
++ *
++ * sys_setpriority is a more generic, but much slower function that
++ * does similar things.
++ */
++SYSCALL_DEFINE1(nice, int, increment)
++{
++ long nice, retval;
++
++ /*
++ * Setpriority might change our priority at the same moment.
++ * We don't have to worry. Conceptually one call occurs first
++ * and we have a single winner.
++ */
++ if (increment < -40)
++ increment = -40;
++ if (increment > 40)
++ increment = 40;
++
++ nice = TASK_NICE(current) + increment;
++ if (nice < -20)
++ nice = -20;
++ if (nice > 19)
++ nice = 19;
++
++ if (increment < 0 && !can_nice(current, nice))
++ return -EPERM;
++
++ retval = security_task_setnice(current, nice);
++ if (retval)
++ return retval;
++
++ set_user_nice(current, nice);
++ return 0;
++}
++
++#endif
++
++/**
++ * task_prio - return the priority value of a given task.
++ * @p: the task in question.
++ *
++ * This is the priority value as seen by users in /proc.
++ * RT tasks are offset by -100. Normal tasks are centered around 1, value goes
++ * from 0 (SCHED_ISO) up to 82 (nice +19 SCHED_IDLEPRIO).
++ */
++int task_prio(const struct task_struct *p)
++{
++ int delta, prio = p->prio - MAX_RT_PRIO;
++
++ /* rt tasks and iso tasks */
++ if (prio <= 0)
++ goto out;
++
++ /* Convert to ms to avoid overflows */
++ delta = NS_TO_MS(p->deadline - grq.niffies);
++ delta = delta * 40 / ms_longest_deadline_diff();
++ if (delta > 0 && delta <= 80)
++ prio += delta;
++ if (idleprio_task(p))
++ prio += 40;
++out:
++ return prio;
++}
++
++/**
++ * task_nice - return the nice value of a given task.
++ * @p: the task in question.
++ */
++int task_nice(const struct task_struct *p)
++{
++ return TASK_NICE(p);
++}
++EXPORT_SYMBOL_GPL(task_nice);
++
++/**
++ * idle_cpu - is a given cpu idle currently?
++ * @cpu: the processor in question.
++ */
++int idle_cpu(int cpu)
++{
++ return cpu_curr(cpu) == cpu_rq(cpu)->idle;
++}
++
++/**
++ * idle_task - return the idle task for a given cpu.
++ * @cpu: the processor in question.
++ */
++struct task_struct *idle_task(int cpu)
++{
++ return cpu_rq(cpu)->idle;
++}
++
++/**
++ * find_process_by_pid - find a process with a matching PID value.
++ * @pid: the pid in question.
++ */
++static inline struct task_struct *find_process_by_pid(pid_t pid)
++{
++ return pid ? find_task_by_vpid(pid) : current;
++}
++
++/* Actually do priority change: must hold grq lock. */
++static void
++__setscheduler(struct task_struct *p, struct rq *rq, int policy, int prio)
++{
++ int oldrtprio, oldprio;
++
++ BUG_ON(task_queued(p));
++
++ p->policy = policy;
++ oldrtprio = p->rt_priority;
++ p->rt_priority = prio;
++ p->normal_prio = normal_prio(p);
++ oldprio = p->prio;
++ /* we are holding p->pi_lock already */
++ p->prio = rt_mutex_getprio(p);
++ if (task_running(p)) {
++ reset_rq_task(rq, p);
++ /* Resched only if we might now be preempted */
++ if (p->prio > oldprio || p->rt_priority > oldrtprio)
++ resched_task(p);
++ }
++}
++
++/*
++ * check the target process has a UID that matches the current process's
++ */
++static bool check_same_owner(struct task_struct *p)
++{
++ const struct cred *cred = current_cred(), *pcred;
++ bool match;
++
++ rcu_read_lock();
++ pcred = __task_cred(p);
++ match = (cred->euid == pcred->euid ||
++ cred->euid == pcred->uid);
++ rcu_read_unlock();
++ return match;
++}
++
++static int __sched_setscheduler(struct task_struct *p, int policy,
++ struct sched_param *param, bool user)
++{
++ struct sched_param zero_param = { .sched_priority = 0 };
++ int queued, retval, oldpolicy = -1;
++ unsigned long flags, rlim_rtprio = 0;
++ int reset_on_fork;
++ struct rq *rq;
++
++ /* may grab non-irq protected spin_locks */
++ BUG_ON(in_interrupt());
++
++ if (is_rt_policy(policy) && !capable(CAP_SYS_NICE)) {
++ unsigned long lflags;
++
++ if (!lock_task_sighand(p, &lflags))
++ return -ESRCH;
++ rlim_rtprio = task_rlimit(p, RLIMIT_RTPRIO);
++ unlock_task_sighand(p, &lflags);
++ if (rlim_rtprio)
++ goto recheck;
++ /*
++ * If the caller requested an RT policy without having the
++ * necessary rights, we downgrade the policy to SCHED_ISO.
++ * We also set the parameter to zero to pass the checks.
++ */
++ policy = SCHED_ISO;
++ param = &zero_param;
++ }
++recheck:
++ /* double check policy once rq lock held */
++ if (policy < 0) {
++ reset_on_fork = p->sched_reset_on_fork;
++ policy = oldpolicy = p->policy;
++ } else {
++ reset_on_fork = !!(policy & SCHED_RESET_ON_FORK);
++ policy &= ~SCHED_RESET_ON_FORK;
++
++ if (!SCHED_RANGE(policy))
++ return -EINVAL;
++ }
++
++ /*
++ * Valid priorities for SCHED_FIFO and SCHED_RR are
++ * 1..MAX_USER_RT_PRIO-1, valid priority for SCHED_NORMAL and
++ * SCHED_BATCH is 0.
++ */
++ if (param->sched_priority < 0 ||
++ (p->mm && param->sched_priority > MAX_USER_RT_PRIO - 1) ||
++ (!p->mm && param->sched_priority > MAX_RT_PRIO - 1))
++ return -EINVAL;
++ if (is_rt_policy(policy) != (param->sched_priority != 0))
++ return -EINVAL;
++
++ /*
++ * Allow unprivileged RT tasks to decrease priority:
++ */
++ if (user && !capable(CAP_SYS_NICE)) {
++ if (is_rt_policy(policy)) {
++ unsigned long rlim_rtprio =
++ task_rlimit(p, RLIMIT_RTPRIO);
++
++ /* can't set/change the rt policy */
++ if (policy != p->policy && !rlim_rtprio)
++ return -EPERM;
++
++ /* can't increase priority */
++ if (param->sched_priority > p->rt_priority &&
++ param->sched_priority > rlim_rtprio)
++ return -EPERM;
++ } else {
++ switch (p->policy) {
++ /*
++ * Can only downgrade policies but not back to
++ * SCHED_NORMAL
++ */
++ case SCHED_ISO:
++ if (policy == SCHED_ISO)
++ goto out;
++ if (policy == SCHED_NORMAL)
++ return -EPERM;
++ break;
++ case SCHED_BATCH:
++ if (policy == SCHED_BATCH)
++ goto out;
++ if (policy != SCHED_IDLEPRIO)
++ return -EPERM;
++ break;
++ case SCHED_IDLEPRIO:
++ if (policy == SCHED_IDLEPRIO)
++ goto out;
++ return -EPERM;
++ default:
++ break;
++ }
++ }
++
++ /* can't change other user's priorities */
++ if (!check_same_owner(p))
++ return -EPERM;
++
++ /* Normal users shall not reset the sched_reset_on_fork flag */
++ if (p->sched_reset_on_fork && !reset_on_fork)
++ return -EPERM;
++ }
++
++ if (user) {
++ retval = security_task_setscheduler(p);
++ if (retval)
++ return retval;
++ }
++
++ /*
++ * make sure no PI-waiters arrive (or leave) while we are
++ * changing the priority of the task:
++ */
++ raw_spin_lock_irqsave(&p->pi_lock, flags);
++ /*
++ * To be able to change p->policy safely, the apropriate
++ * runqueue lock must be held.
++ */
++ rq = __task_grq_lock(p);
++
++ /*
++ * Changing the policy of the stop threads its a very bad idea
++ */
++ if (p == rq->stop) {
++ __task_grq_unlock();
++ raw_spin_unlock_irqrestore(&p->pi_lock, flags);
++ return -EINVAL;
++ }
++
++ /* recheck policy now with rq lock held */
++ if (unlikely(oldpolicy != -1 && oldpolicy != p->policy)) {
++ policy = oldpolicy = -1;
++ __task_grq_unlock();
++ raw_spin_unlock_irqrestore(&p->pi_lock, flags);
++ goto recheck;
++ }
++ update_clocks(rq);
++ p->sched_reset_on_fork = reset_on_fork;
++
++ queued = task_queued(p);
++ if (queued)
++ dequeue_task(p);
++ __setscheduler(p, rq, policy, param->sched_priority);
++ if (queued) {
++ enqueue_task(p);
++ try_preempt(p, rq);
++ }
++ __task_grq_unlock();
++ raw_spin_unlock_irqrestore(&p->pi_lock, flags);
++
++ rt_mutex_adjust_pi(p);
++out:
++ return 0;
++}
++
++/**
++ * sched_setscheduler - change the scheduling policy and/or RT priority of a thread.
++ * @p: the task in question.
++ * @policy: new policy.
++ * @param: structure containing the new RT priority.
++ *
++ * NOTE that the task may be already dead.
++ */
++int sched_setscheduler(struct task_struct *p, int policy,
++ struct sched_param *param)
++{
++ return __sched_setscheduler(p, policy, param, true);
++}
++
++EXPORT_SYMBOL_GPL(sched_setscheduler);
++
++/**
++ * sched_setscheduler_nocheck - change the scheduling policy and/or RT priority of a thread from kernelspace.
++ * @p: the task in question.
++ * @policy: new policy.
++ * @param: structure containing the new RT priority.
++ *
++ * Just like sched_setscheduler, only don't bother checking if the
++ * current context has permission. For example, this is needed in
++ * stop_machine(): we create temporary high priority worker threads,
++ * but our caller might not have that capability.
++ */
++int sched_setscheduler_nocheck(struct task_struct *p, int policy,
++ struct sched_param *param)
++{
++ return __sched_setscheduler(p, policy, param, false);
++}
++
++static int
++do_sched_setscheduler(pid_t pid, int policy, struct sched_param __user *param)
++{
++ struct sched_param lparam;
++ struct task_struct *p;
++ int retval;
++
++ if (!param || pid < 0)
++ return -EINVAL;
++ if (copy_from_user(&lparam, param, sizeof(struct sched_param)))
++ return -EFAULT;
++
++ rcu_read_lock();
++ retval = -ESRCH;
++ p = find_process_by_pid(pid);
++ if (p != NULL)
++ retval = sched_setscheduler(p, policy, &lparam);
++ rcu_read_unlock();
++
++ return retval;
++}
++
++/**
++ * sys_sched_setscheduler - set/change the scheduler policy and RT priority
++ * @pid: the pid in question.
++ * @policy: new policy.
++ * @param: structure containing the new RT priority.
++ */
++asmlinkage long sys_sched_setscheduler(pid_t pid, int policy,
++ struct sched_param __user *param)
++{
++ /* negative values for policy are not valid */
++ if (policy < 0)
++ return -EINVAL;
++
++ return do_sched_setscheduler(pid, policy, param);
++}
++
++/**
++ * sys_sched_setparam - set/change the RT priority of a thread
++ * @pid: the pid in question.
++ * @param: structure containing the new RT priority.
++ */
++SYSCALL_DEFINE2(sched_setparam, pid_t, pid, struct sched_param __user *, param)
++{
++ return do_sched_setscheduler(pid, -1, param);
++}
++
++/**
++ * sys_sched_getscheduler - get the policy (scheduling class) of a thread
++ * @pid: the pid in question.
++ */
++SYSCALL_DEFINE1(sched_getscheduler, pid_t, pid)
++{
++ struct task_struct *p;
++ int retval = -EINVAL;
++
++ if (pid < 0)
++ goto out_nounlock;
++
++ retval = -ESRCH;
++ rcu_read_lock();
++ p = find_process_by_pid(pid);
++ if (p) {
++ retval = security_task_getscheduler(p);
++ if (!retval)
++ retval = p->policy;
++ }
++ rcu_read_unlock();
++
++out_nounlock:
++ return retval;
++}
++
++/**
++ * sys_sched_getscheduler - get the RT priority of a thread
++ * @pid: the pid in question.
++ * @param: structure containing the RT priority.
++ */
++SYSCALL_DEFINE2(sched_getparam, pid_t, pid, struct sched_param __user *, param)
++{
++ struct sched_param lp;
++ struct task_struct *p;
++ int retval = -EINVAL;
++
++ if (!param || pid < 0)
++ goto out_nounlock;
++
++ rcu_read_lock();
++ p = find_process_by_pid(pid);
++ retval = -ESRCH;
++ if (!p)
++ goto out_unlock;
++
++ retval = security_task_getscheduler(p);
++ if (retval)
++ goto out_unlock;
++
++ lp.sched_priority = p->rt_priority;
++ rcu_read_unlock();
++
++ /*
++ * This one might sleep, we cannot do it with a spinlock held ...
++ */
++ retval = copy_to_user(param, &lp, sizeof(*param)) ? -EFAULT : 0;
++
++out_nounlock:
++ return retval;
++
++out_unlock:
++ rcu_read_unlock();
++ return retval;
++}
++
++long sched_setaffinity(pid_t pid, const struct cpumask *in_mask)
++{
++ cpumask_var_t cpus_allowed, new_mask;
++ struct task_struct *p;
++ int retval;
++
++ get_online_cpus();
++ rcu_read_lock();
++
++ p = find_process_by_pid(pid);
++ if (!p) {
++ rcu_read_unlock();
++ put_online_cpus();
++ return -ESRCH;
++ }
++
++ /* Prevent p going away */
++ get_task_struct(p);
++ rcu_read_unlock();
++
++ if (!alloc_cpumask_var(&cpus_allowed, GFP_KERNEL)) {
++ retval = -ENOMEM;
++ goto out_put_task;
++ }
++ if (!alloc_cpumask_var(&new_mask, GFP_KERNEL)) {
++ retval = -ENOMEM;
++ goto out_free_cpus_allowed;
++ }
++ retval = -EPERM;
++ if (!check_same_owner(p) && !capable(CAP_SYS_NICE))
++ goto out_unlock;
++
++ retval = security_task_setscheduler(p);
++ if (retval)
++ goto out_unlock;
++
++ cpuset_cpus_allowed(p, cpus_allowed);
++ cpumask_and(new_mask, in_mask, cpus_allowed);
++again:
++ retval = set_cpus_allowed_ptr(p, new_mask);
++
++ if (!retval) {
++ cpuset_cpus_allowed(p, cpus_allowed);
++ if (!cpumask_subset(new_mask, cpus_allowed)) {
++ /*
++ * We must have raced with a concurrent cpuset
++ * update. Just reset the cpus_allowed to the
++ * cpuset's cpus_allowed
++ */
++ cpumask_copy(new_mask, cpus_allowed);
++ goto again;
++ }
++ }
++out_unlock:
++ free_cpumask_var(new_mask);
++out_free_cpus_allowed:
++ free_cpumask_var(cpus_allowed);
++out_put_task:
++ put_task_struct(p);
++ put_online_cpus();
++ return retval;
++}
++
++static int get_user_cpu_mask(unsigned long __user *user_mask_ptr, unsigned len,
++ cpumask_t *new_mask)
++{
++ if (len < sizeof(cpumask_t)) {
++ memset(new_mask, 0, sizeof(cpumask_t));
++ } else if (len > sizeof(cpumask_t)) {
++ len = sizeof(cpumask_t);
++ }
++ return copy_from_user(new_mask, user_mask_ptr, len) ? -EFAULT : 0;
++}
++
++
++/**
++ * sys_sched_setaffinity - set the cpu affinity of a process
++ * @pid: pid of the process
++ * @len: length in bytes of the bitmask pointed to by user_mask_ptr
++ * @user_mask_ptr: user-space pointer to the new cpu mask
++ */
++SYSCALL_DEFINE3(sched_setaffinity, pid_t, pid, unsigned int, len,
++ unsigned long __user *, user_mask_ptr)
++{
++ cpumask_var_t new_mask;
++ int retval;
++
++ if (!alloc_cpumask_var(&new_mask, GFP_KERNEL))
++ return -ENOMEM;
++
++ retval = get_user_cpu_mask(user_mask_ptr, len, new_mask);
++ if (retval == 0)
++ retval = sched_setaffinity(pid, new_mask);
++ free_cpumask_var(new_mask);
++ return retval;
++}
++
++long sched_getaffinity(pid_t pid, cpumask_t *mask)
++{
++ struct task_struct *p;
++ unsigned long flags;
++ struct rq *rq;
++ int retval;
++
++ get_online_cpus();
++ rcu_read_lock();
++
++ retval = -ESRCH;
++ p = find_process_by_pid(pid);
++ if (!p)
++ goto out_unlock;
++
++ retval = security_task_getscheduler(p);
++ if (retval)
++ goto out_unlock;
++
++ rq = task_grq_lock(p, &flags);
++ cpumask_and(mask, &p->cpus_allowed, cpu_online_mask);
++ task_grq_unlock(&flags);
++
++out_unlock:
++ rcu_read_unlock();
++ put_online_cpus();
++
++ return retval;
++}
++
++/**
++ * sys_sched_getaffinity - get the cpu affinity of a process
++ * @pid: pid of the process
++ * @len: length in bytes of the bitmask pointed to by user_mask_ptr
++ * @user_mask_ptr: user-space pointer to hold the current cpu mask
++ */
++SYSCALL_DEFINE3(sched_getaffinity, pid_t, pid, unsigned int, len,
++ unsigned long __user *, user_mask_ptr)
++{
++ int ret;
++ cpumask_var_t mask;
++
++ if ((len * BITS_PER_BYTE) < nr_cpu_ids)
++ return -EINVAL;
++ if (len & (sizeof(unsigned long)-1))
++ return -EINVAL;
++
++ if (!alloc_cpumask_var(&mask, GFP_KERNEL))
++ return -ENOMEM;
++
++ ret = sched_getaffinity(pid, mask);
++ if (ret == 0) {
++ size_t retlen = min_t(size_t, len, cpumask_size());
++
++ if (copy_to_user(user_mask_ptr, mask, retlen))
++ ret = -EFAULT;
++ else
++ ret = retlen;
++ }
++ free_cpumask_var(mask);
++
++ return ret;
++}
++
++/**
++ * sys_sched_yield - yield the current processor to other threads.
++ *
++ * This function yields the current CPU to other tasks. It does this by
++ * scheduling away the current task. If it still has the earliest deadline
++ * it will be scheduled again as the next task.
++ */
++SYSCALL_DEFINE0(sched_yield)
++{
++ struct task_struct *p;
++ struct rq *rq;
++
++ p = current;
++ rq = task_grq_lock_irq(p);
++ schedstat_inc(rq, yld_count);
++ requeue_task(p);
++
++ /*
++ * Since we are going to call schedule() anyway, there's
++ * no need to preempt or enable interrupts:
++ */
++ __release(grq.lock);
++ spin_release(&grq.lock.dep_map, 1, _THIS_IP_);
++ do_raw_spin_unlock(&grq.lock);
++ preempt_enable_no_resched();
++
++ schedule();
++
++ return 0;
++}
++
++static inline int should_resched(void)
++{
++ return need_resched() && !(preempt_count() & PREEMPT_ACTIVE);
++}
++
++static void __cond_resched(void)
++{
++ /* NOT a real fix but will make voluntary preempt work. 馬鹿な事 */
++ if (unlikely(system_state != SYSTEM_RUNNING))
++ return;
++
++ add_preempt_count(PREEMPT_ACTIVE);
++ schedule();
++ sub_preempt_count(PREEMPT_ACTIVE);
++}
++
++int __sched _cond_resched(void)
++{
++ if (should_resched()) {
++ __cond_resched();
++ return 1;
++ }
++ return 0;
++}
++EXPORT_SYMBOL(_cond_resched);
++
++/*
++ * __cond_resched_lock() - if a reschedule is pending, drop the given lock,
++ * call schedule, and on return reacquire the lock.
++ *
++ * This works OK both with and without CONFIG_PREEMPT. We do strange low-level
++ * operations here to prevent schedule() from being called twice (once via
++ * spin_unlock(), once by hand).
++ */
++int __cond_resched_lock(spinlock_t *lock)
++{
++ int resched = should_resched();
++ int ret = 0;
++
++ lockdep_assert_held(lock);
++
++ if (spin_needbreak(lock) || resched) {
++ spin_unlock(lock);
++ if (resched)
++ __cond_resched();
++ else
++ cpu_relax();
++ ret = 1;
++ spin_lock(lock);
++ }
++ return ret;
++}
++EXPORT_SYMBOL(__cond_resched_lock);
++
++int __sched __cond_resched_softirq(void)
++{
++ BUG_ON(!in_softirq());
++
++ if (should_resched()) {
++ local_bh_enable();
++ __cond_resched();
++ local_bh_disable();
++ return 1;
++ }
++ return 0;
++}
++EXPORT_SYMBOL(__cond_resched_softirq);
++
++/**
++ * yield - yield the current processor to other threads.
++ *
++ * This is a shortcut for kernel-space yielding - it marks the
++ * thread runnable and calls sys_sched_yield().
++ */
++void __sched yield(void)
++{
++ set_current_state(TASK_RUNNING);
++ sys_sched_yield();
++}
++EXPORT_SYMBOL(yield);
++
++/*
++ * This task is about to go to sleep on IO. Increment rq->nr_iowait so
++ * that process accounting knows that this is a task in IO wait state.
++ *
++ * But don't do that if it is a deliberate, throttling IO wait (this task
++ * has set its backing_dev_info: the queue against which it should throttle)
++ */
++void __sched io_schedule(void)
++{
++ struct rq *rq = raw_rq();
++
++ delayacct_blkio_start();
++ atomic_inc(&rq->nr_iowait);
++ current->in_iowait = 1;
++ schedule();
++ current->in_iowait = 0;
++ atomic_dec(&rq->nr_iowait);
++ delayacct_blkio_end();
++}
++EXPORT_SYMBOL(io_schedule);
++
++long __sched io_schedule_timeout(long timeout)
++{
++ struct rq *rq = raw_rq();
++ long ret;
++
++ delayacct_blkio_start();
++ atomic_inc(&rq->nr_iowait);
++ current->in_iowait = 1;
++ ret = schedule_timeout(timeout);
++ current->in_iowait = 0;
++ atomic_dec(&rq->nr_iowait);
++ delayacct_blkio_end();
++ return ret;
++}
++
++/**
++ * sys_sched_get_priority_max - return maximum RT priority.
++ * @policy: scheduling class.
++ *
++ * this syscall returns the maximum rt_priority that can be used
++ * by a given scheduling class.
++ */
++SYSCALL_DEFINE1(sched_get_priority_max, int, policy)
++{
++ int ret = -EINVAL;
++
++ switch (policy) {
++ case SCHED_FIFO:
++ case SCHED_RR:
++ ret = MAX_USER_RT_PRIO-1;
++ break;
++ case SCHED_NORMAL:
++ case SCHED_BATCH:
++ case SCHED_ISO:
++ case SCHED_IDLEPRIO:
++ ret = 0;
++ break;
++ }
++ return ret;
++}
++
++/**
++ * sys_sched_get_priority_min - return minimum RT priority.
++ * @policy: scheduling class.
++ *
++ * this syscall returns the minimum rt_priority that can be used
++ * by a given scheduling class.
++ */
++SYSCALL_DEFINE1(sched_get_priority_min, int, policy)
++{
++ int ret = -EINVAL;
++
++ switch (policy) {
++ case SCHED_FIFO:
++ case SCHED_RR:
++ ret = 1;
++ break;
++ case SCHED_NORMAL:
++ case SCHED_BATCH:
++ case SCHED_ISO:
++ case SCHED_IDLEPRIO:
++ ret = 0;
++ break;
++ }
++ return ret;
++}
++
++/**
++ * sys_sched_rr_get_interval - return the default timeslice of a process.
++ * @pid: pid of the process.
++ * @interval: userspace pointer to the timeslice value.
++ *
++ * this syscall writes the default timeslice value of a given process
++ * into the user-space timespec buffer. A value of '0' means infinity.
++ */
++SYSCALL_DEFINE2(sched_rr_get_interval, pid_t, pid,
++ struct timespec __user *, interval)
++{
++ struct task_struct *p;
++ unsigned int time_slice;
++ unsigned long flags;
++ struct rq *rq;
++ int retval;
++ struct timespec t;
++
++ if (pid < 0)
++ return -EINVAL;
++
++ retval = -ESRCH;
++ rcu_read_lock();
++ p = find_process_by_pid(pid);
++ if (!p)
++ goto out_unlock;
++
++ retval = security_task_getscheduler(p);
++ if (retval)
++ goto out_unlock;
++
++ rq = task_grq_lock(p, &flags);
++ time_slice = p->policy == SCHED_FIFO ? 0 : MS_TO_NS(task_timeslice(p));
++ task_grq_unlock(&flags);
++
++ rcu_read_unlock();
++ t = ns_to_timespec(time_slice);
++ retval = copy_to_user(interval, &t, sizeof(t)) ? -EFAULT : 0;
++ return retval;
++
++out_unlock:
++ rcu_read_unlock();
++ return retval;
++}
++
++static const char stat_nam[] = TASK_STATE_TO_CHAR_STR;
++
++void sched_show_task(struct task_struct *p)
++{
++ unsigned long free = 0;
++ unsigned state;
++
++ state = p->state ? __ffs(p->state) + 1 : 0;
++ printk(KERN_INFO "%-13.13s %c", p->comm,
++ state < sizeof(stat_nam) - 1 ? stat_nam[state] : '?');
++#if BITS_PER_LONG == 32
++ if (state == TASK_RUNNING)
++ printk(KERN_CONT " running ");
++ else
++ printk(KERN_CONT " %08lx ", thread_saved_pc(p));
++#else
++ if (state == TASK_RUNNING)
++ printk(KERN_CONT " running task ");
++ else
++ printk(KERN_CONT " %016lx ", thread_saved_pc(p));
++#endif
++#ifdef CONFIG_DEBUG_STACK_USAGE
++ free = stack_not_used(p);
++#endif
++ printk(KERN_CONT "%5lu %5d %6d 0x%08lx\n", free,
++ task_pid_nr(p), task_pid_nr(p->real_parent),
++ (unsigned long)task_thread_info(p)->flags);
++
++ show_stack(p, NULL);
++}
++
++void show_state_filter(unsigned long state_filter)
++{
++ struct task_struct *g, *p;
++
++#if BITS_PER_LONG == 32
++ printk(KERN_INFO
++ " task PC stack pid father\n");
++#else
++ printk(KERN_INFO
++ " task PC stack pid father\n");
++#endif
++ read_lock(&tasklist_lock);
++ do_each_thread(g, p) {
++ /*
++ * reset the NMI-timeout, listing all files on a slow
++ * console might take alot of time:
++ */
++ touch_nmi_watchdog();
++ if (!state_filter || (p->state & state_filter))
++ sched_show_task(p);
++ } while_each_thread(g, p);
++
++ touch_all_softlockup_watchdogs();
++
++ read_unlock(&tasklist_lock);
++ /*
++ * Only show locks if all tasks are dumped:
++ */
++ if (!state_filter)
++ debug_show_all_locks();
++}
++
++/**
++ * init_idle - set up an idle thread for a given CPU
++ * @idle: task in question
++ * @cpu: cpu the idle task belongs to
++ *
++ * NOTE: this function does not set the idle thread's NEED_RESCHED
++ * flag, to make booting more robust.
++ */
++void init_idle(struct task_struct *idle, int cpu)
++{
++ struct rq *rq = cpu_rq(cpu);
++ unsigned long flags;
++
++ time_grq_lock(rq, &flags);
++ idle->last_ran = rq->clock;
++ idle->state = TASK_RUNNING;
++ /* Setting prio to illegal value shouldn't matter when never queued */
++ idle->prio = PRIO_LIMIT;
++ set_rq_task(rq, idle);
++ idle->cpus_allowed = cpumask_of_cpu(cpu);
++ /* Silence PROVE_RCU */
++ rcu_read_lock();
++ set_task_cpu(idle, cpu);
++ rcu_read_unlock();
++ rq->curr = rq->idle = idle;
++ idle->oncpu = 1;
++ set_cpuidle_map(cpu);
++ grq_unlock_irqrestore(&flags);
++
++ /* Set the preempt count _outside_ the spinlocks! */
++#if defined(CONFIG_PREEMPT) && !defined(CONFIG_PREEMPT_BKL)
++ task_thread_info(idle)->preempt_count = (idle->lock_depth >= 0);
++#else
++ task_thread_info(idle)->preempt_count = 0;
++#endif
++ ftrace_graph_init_task(idle);
++}
++
++/*
++ * In a system that switches off the HZ timer nohz_cpu_mask
++ * indicates which cpus entered this state. This is used
++ * in the rcu update to wait only for active cpus. For system
++ * which do not switch off the HZ timer nohz_cpu_mask should
++ * always be CPU_BITS_NONE.
++ */
++cpumask_var_t nohz_cpu_mask;
++
++#ifdef CONFIG_SMP
++#ifdef CONFIG_NO_HZ
++void select_nohz_load_balancer(int stop_tick)
++{
++}
++#if defined(CONFIG_SCHED_MC) || defined(CONFIG_SCHED_SMT)
++/**
++ * lowest_flag_domain - Return lowest sched_domain containing flag.
++ * @cpu: The cpu whose lowest level of sched domain is to
++ * be returned.
++ * @flag: The flag to check for the lowest sched_domain
++ * for the given cpu.
++ *
++ * Returns the lowest sched_domain of a cpu which contains the given flag.
++ */
++static inline struct sched_domain *lowest_flag_domain(int cpu, int flag)
++{
++ struct sched_domain *sd;
++
++ for_each_domain(cpu, sd)
++ if (sd && (sd->flags & flag))
++ break;
++
++ return sd;
++}
++
++/**
++ * for_each_flag_domain - Iterates over sched_domains containing the flag.
++ * @cpu: The cpu whose domains we're iterating over.
++ * @sd: variable holding the value of the power_savings_sd
++ * for cpu.
++ * @flag: The flag to filter the sched_domains to be iterated.
++ *
++ * Iterates over all the scheduler domains for a given cpu that has the 'flag'
++ * set, starting from the lowest sched_domain to the highest.
++ */
++#define for_each_flag_domain(cpu, sd, flag) \
++ for (sd = lowest_flag_domain(cpu, flag); \
++ (sd && (sd->flags & flag)); sd = sd->parent)
++
++#endif /* (CONFIG_SCHED_MC || CONFIG_SCHED_SMT) */
++
++static inline void resched_cpu(int cpu)
++{
++ unsigned long flags;
++
++ grq_lock_irqsave(&flags);
++ resched_task(cpu_curr(cpu));
++ grq_unlock_irqrestore(&flags);
++}
++
++/*
++ * In the semi idle case, use the nearest busy cpu for migrating timers
++ * from an idle cpu. This is good for power-savings.
++ *
++ * We don't do similar optimization for completely idle system, as
++ * selecting an idle cpu will add more delays to the timers than intended
++ * (as that cpu's timer base may not be uptodate wrt jiffies etc).
++ */
++int get_nohz_timer_target(void)
++{
++ int cpu = smp_processor_id();
++ int i;
++ struct sched_domain *sd;
++
++ for_each_domain(cpu, sd) {
++ for_each_cpu(i, sched_domain_span(sd))
++ if (!idle_cpu(i))
++ return i;
++ }
++ return cpu;
++}
++
++/*
++ * When add_timer_on() enqueues a timer into the timer wheel of an
++ * idle CPU then this timer might expire before the next timer event
++ * which is scheduled to wake up that CPU. In case of a completely
++ * idle system the next event might even be infinite time into the
++ * future. wake_up_idle_cpu() ensures that the CPU is woken up and
++ * leaves the inner idle loop so the newly added timer is taken into
++ * account when the CPU goes back to idle and evaluates the timer
++ * wheel for the next timer event.
++ */
++void wake_up_idle_cpu(int cpu)
++{
++ struct task_struct *idle;
++ struct rq *rq;
++
++ if (cpu == smp_processor_id())
++ return;
++
++ rq = cpu_rq(cpu);
++ idle = rq->idle;
++
++ /*
++ * This is safe, as this function is called with the timer
++ * wheel base lock of (cpu) held. When the CPU is on the way
++ * to idle and has not yet set rq->curr to idle then it will
++ * be serialised on the timer wheel base lock and take the new
++ * timer into account automatically.
++ */
++ if (unlikely(rq->curr != idle))
++ return;
++
++ /*
++ * We can set TIF_RESCHED on the idle task of the other CPU
++ * lockless. The worst case is that the other CPU runs the
++ * idle task through an additional NOOP schedule()
++ */
++ set_tsk_need_resched(idle);
++
++ /* NEED_RESCHED must be visible before we test polling */
++ smp_mb();
++ if (!tsk_is_polling(idle))
++ smp_send_reschedule(cpu);
++}
++
++#endif /* CONFIG_NO_HZ */
++
++/*
++ * Change a given task's CPU affinity. Migrate the thread to a
++ * proper CPU and schedule it away if the CPU it's executing on
++ * is removed from the allowed bitmask.
++ *
++ * NOTE: the caller must have a valid reference to the task, the
++ * task must not exit() & deallocate itself prematurely. The
++ * call is not atomic; no spinlocks may be held.
++ */
++int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask)
++{
++ unsigned long flags;
++ int running_wrong = 0;
++ int queued = 0;
++ struct rq *rq;
++ int ret = 0;
++
++ rq = task_grq_lock(p, &flags);
++
++ if (!cpumask_intersects(new_mask, cpu_active_mask)) {
++ ret = -EINVAL;
++ goto out;
++ }
++
++ if (unlikely((p->flags & PF_THREAD_BOUND) && p != current &&
++ !cpumask_equal(&p->cpus_allowed, new_mask))) {
++ ret = -EINVAL;
++ goto out;
++ }
++
++ queued = task_queued(p);
++
++ cpumask_copy(&p->cpus_allowed, new_mask);
++
++ /* Can the task run on the task's current CPU? If so, we're done */
++ if (cpumask_test_cpu(task_cpu(p), new_mask))
++ goto out;
++
++ if (task_running(p)) {
++ /* Task is running on the wrong cpu now, reschedule it. */
++ if (rq == this_rq()) {
++ set_tsk_need_resched(p);
++ running_wrong = 1;
++ } else
++ resched_task(p);
++ } else
++ set_task_cpu(p, cpumask_any_and(cpu_active_mask, new_mask));
++
++out:
++ if (queued)
++ try_preempt(p, rq);
++ task_grq_unlock(&flags);
++
++ if (running_wrong)
++ _cond_resched();
++
++ return ret;
++}
++EXPORT_SYMBOL_GPL(set_cpus_allowed_ptr);
++
++#ifdef CONFIG_HOTPLUG_CPU
++/*
++ * Reschedule a task if it's on a dead CPU.
++ */
++void move_task_off_dead_cpu(int dead_cpu, struct task_struct *p)
++{
++ unsigned long flags;
++ struct rq *rq, *dead_rq;
++
++ dead_rq = cpu_rq(dead_cpu);
++ rq = task_grq_lock(p, &flags);
++ if (rq == dead_rq && task_running(p))
++ resched_task(p);
++ task_grq_unlock(&flags);
++
++}
++
++/* Run through task list and find tasks affined to just the dead cpu, then
++ * allocate a new affinity */
++static void break_sole_affinity(int src_cpu)
++{
++ struct task_struct *p, *t;
++
++ do_each_thread(t, p) {
++ if (!online_cpus(p)) {
++ cpumask_copy(&p->cpus_allowed, cpu_possible_mask);
++ /*
++ * Don't tell them about moving exiting tasks or
++ * kernel threads (both mm NULL), since they never
++ * leave kernel.
++ */
++ if (p->mm && printk_ratelimit()) {
++ printk(KERN_INFO "process %d (%s) no "
++ "longer affine to cpu %d\n",
++ task_pid_nr(p), p->comm, src_cpu);
++ }
++ }
++ } while_each_thread(t, p);
++}
++
++/*
++ * Schedules idle task to be the next runnable task on current CPU.
++ * It does so by boosting its priority to highest possible.
++ * Used by CPU offline code.
++ */
++void sched_idle_next(void)
++{
++ int this_cpu = smp_processor_id();
++ struct rq *rq = cpu_rq(this_cpu);
++ struct task_struct *idle = rq->idle;
++ unsigned long flags;
++
++ /* cpu has to be offline */
++ BUG_ON(cpu_online(this_cpu));
++
++ /*
++ * Strictly not necessary since rest of the CPUs are stopped by now
++ * and interrupts disabled on the current cpu.
++ */
++ grq_lock_irqsave(&flags);
++ break_sole_affinity(this_cpu);
++
++ __setscheduler(idle, rq, SCHED_FIFO, STOP_PRIO);
++
++ activate_idle_task(idle);
++ set_tsk_need_resched(rq->curr);
++
++ grq_unlock_irqrestore(&flags);
++}
++
++/*
++ * Ensures that the idle task is using init_mm right before its cpu goes
++ * offline.
++ */
++void idle_task_exit(void)
++{
++ struct mm_struct *mm = current->active_mm;
++
++ BUG_ON(cpu_online(smp_processor_id()));
++
++ if (mm != &init_mm)
++ switch_mm(mm, &init_mm, current);
++ mmdrop(mm);
++}
++
++#endif /* CONFIG_HOTPLUG_CPU */
++
++void sched_set_stop_task(int cpu, struct task_struct *stop)
++{
++ struct sched_param stop_param = { .sched_priority = STOP_PRIO };
++ struct sched_param start_param = { .sched_priority = MAX_USER_RT_PRIO - 1 };
++ struct task_struct *old_stop = cpu_rq(cpu)->stop;
++
++ if (stop) {
++ /*
++ * Make it appear like a SCHED_FIFO task, its something
++ * userspace knows about and won't get confused about.
++ *
++ * Also, it will make PI more or less work without too
++ * much confusion -- but then, stop work should not
++ * rely on PI working anyway.
++ */
++ sched_setscheduler_nocheck(stop, SCHED_FIFO, &stop_param);
++ }
++
++ cpu_rq(cpu)->stop = stop;
++
++ if (old_stop) {
++ /*
++ * Reset it back to a normal rt scheduling prio so that
++ * it can die in pieces.
++ */
++ sched_setscheduler_nocheck(old_stop, SCHED_FIFO, &start_param);
++ }
++}
++
++#if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_SYSCTL)
++
++static struct ctl_table sd_ctl_dir[] = {
++ {
++ .procname = "sched_domain",
++ .mode = 0555,
++ },
++ {}
++};
++
++static struct ctl_table sd_ctl_root[] = {
++ {
++ .procname = "kernel",
++ .mode = 0555,
++ .child = sd_ctl_dir,
++ },
++ {}
++};
++
++static struct ctl_table *sd_alloc_ctl_entry(int n)
++{
++ struct ctl_table *entry =
++ kcalloc(n, sizeof(struct ctl_table), GFP_KERNEL);
++
++ return entry;
++}
++
++static void sd_free_ctl_entry(struct ctl_table **tablep)
++{
++ struct ctl_table *entry;
++
++ /*
++ * In the intermediate directories, both the child directory and
++ * procname are dynamically allocated and could fail but the mode
++ * will always be set. In the lowest directory the names are
++ * static strings and all have proc handlers.
++ */
++ for (entry = *tablep; entry->mode; entry++) {
++ if (entry->child)
++ sd_free_ctl_entry(&entry->child);
++ if (entry->proc_handler == NULL)
++ kfree(entry->procname);
++ }
++
++ kfree(*tablep);
++ *tablep = NULL;
++}
++
++static void
++set_table_entry(struct ctl_table *entry,
++ const char *procname, void *data, int maxlen,
++ mode_t mode, proc_handler *proc_handler)
++{
++ entry->procname = procname;
++ entry->data = data;
++ entry->maxlen = maxlen;
++ entry->mode = mode;
++ entry->proc_handler = proc_handler;
++}
++
++static struct ctl_table *
++sd_alloc_ctl_domain_table(struct sched_domain *sd)
++{
++ struct ctl_table *table = sd_alloc_ctl_entry(13);
++
++ if (table == NULL)
++ return NULL;
++
++ set_table_entry(&table[0], "min_interval", &sd->min_interval,
++ sizeof(long), 0644, proc_doulongvec_minmax);
++ set_table_entry(&table[1], "max_interval", &sd->max_interval,
++ sizeof(long), 0644, proc_doulongvec_minmax);
++ set_table_entry(&table[2], "busy_idx", &sd->busy_idx,
++ sizeof(int), 0644, proc_dointvec_minmax);
++ set_table_entry(&table[3], "idle_idx", &sd->idle_idx,
++ sizeof(int), 0644, proc_dointvec_minmax);
++ set_table_entry(&table[4], "newidle_idx", &sd->newidle_idx,
++ sizeof(int), 0644, proc_dointvec_minmax);
++ set_table_entry(&table[5], "wake_idx", &sd->wake_idx,
++ sizeof(int), 0644, proc_dointvec_minmax);
++ set_table_entry(&table[6], "forkexec_idx", &sd->forkexec_idx,
++ sizeof(int), 0644, proc_dointvec_minmax);
++ set_table_entry(&table[7], "busy_factor", &sd->busy_factor,
++ sizeof(int), 0644, proc_dointvec_minmax);
++ set_table_entry(&table[8], "imbalance_pct", &sd->imbalance_pct,
++ sizeof(int), 0644, proc_dointvec_minmax);
++ set_table_entry(&table[9], "cache_nice_tries",
++ &sd->cache_nice_tries,
++ sizeof(int), 0644, proc_dointvec_minmax);
++ set_table_entry(&table[10], "flags", &sd->flags,
++ sizeof(int), 0644, proc_dointvec_minmax);
++ set_table_entry(&table[11], "name", sd->name,
++ CORENAME_MAX_SIZE, 0444, proc_dostring);
++ /* &table[12] is terminator */
++
++ return table;
++}
++
++static ctl_table *sd_alloc_ctl_cpu_table(int cpu)
++{
++ struct ctl_table *entry, *table;
++ struct sched_domain *sd;
++ int domain_num = 0, i;
++ char buf[32];
++
++ for_each_domain(cpu, sd)
++ domain_num++;
++ entry = table = sd_alloc_ctl_entry(domain_num + 1);
++ if (table == NULL)
++ return NULL;
++
++ i = 0;
++ for_each_domain(cpu, sd) {
++ snprintf(buf, 32, "domain%d", i);
++ entry->procname = kstrdup(buf, GFP_KERNEL);
++ entry->mode = 0555;
++ entry->child = sd_alloc_ctl_domain_table(sd);
++ entry++;
++ i++;
++ }
++ return table;
++}
++
++static struct ctl_table_header *sd_sysctl_header;
++static void register_sched_domain_sysctl(void)
++{
++ int i, cpu_num = num_possible_cpus();
++ struct ctl_table *entry = sd_alloc_ctl_entry(cpu_num + 1);
++ char buf[32];
++
++ WARN_ON(sd_ctl_dir[0].child);
++ sd_ctl_dir[0].child = entry;
++
++ if (entry == NULL)
++ return;
++
++ for_each_possible_cpu(i) {
++ snprintf(buf, 32, "cpu%d", i);
++ entry->procname = kstrdup(buf, GFP_KERNEL);
++ entry->mode = 0555;
++ entry->child = sd_alloc_ctl_cpu_table(i);
++ entry++;
++ }
++
++ WARN_ON(sd_sysctl_header);
++ sd_sysctl_header = register_sysctl_table(sd_ctl_root);
++}
++
++/* may be called multiple times per register */
++static void unregister_sched_domain_sysctl(void)
++{
++ if (sd_sysctl_header)
++ unregister_sysctl_table(sd_sysctl_header);
++ sd_sysctl_header = NULL;
++ if (sd_ctl_dir[0].child)
++ sd_free_ctl_entry(&sd_ctl_dir[0].child);
++}
++#else
++static void register_sched_domain_sysctl(void)
++{
++}
++static void unregister_sched_domain_sysctl(void)
++{
++}
++#endif
++
++static void set_rq_online(struct rq *rq)
++{
++ if (!rq->online) {
++ cpumask_set_cpu(cpu_of(rq), rq->rd->online);
++ rq->online = 1;
++ }
++}
++
++static void set_rq_offline(struct rq *rq)
++{
++ if (rq->online) {
++ cpumask_clear_cpu(cpu_of(rq), rq->rd->online);
++ rq->online = 0;
++ }
++}
++
++/*
++ * migration_call - callback that gets triggered when a CPU is added.
++ */
++static int __cpuinit
++migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
++{
++#ifdef CONFIG_HOTPLUG_CPU
++ struct task_struct *idle;
++#endif
++ int cpu = (long)hcpu;
++ unsigned long flags;
++ struct rq *rq = cpu_rq(cpu);
++
++ switch (action) {
++
++ case CPU_UP_PREPARE:
++ case CPU_UP_PREPARE_FROZEN:
++ break;
++
++ case CPU_ONLINE:
++ case CPU_ONLINE_FROZEN:
++ /* Update our root-domain */
++ grq_lock_irqsave(&flags);
++ if (rq->rd) {
++ BUG_ON(!cpumask_test_cpu(cpu, rq->rd->span));
++
++ set_rq_online(rq);
++ }
++ grq_unlock_irqrestore(&flags);
++ break;
++
++#ifdef CONFIG_HOTPLUG_CPU
++ case CPU_DEAD:
++ case CPU_DEAD_FROZEN:
++ idle = rq->idle;
++ /* Idle task back to normal (off runqueue, low prio) */
++ grq_lock_irq();
++ return_task(idle, 1);
++ idle->static_prio = MAX_PRIO;
++ __setscheduler(idle, rq, SCHED_NORMAL, 0);
++ idle->prio = PRIO_LIMIT;
++ set_rq_task(rq, idle);
++ update_clocks(rq);
++ grq_unlock_irq();
++ break;
++
++ case CPU_DYING:
++ case CPU_DYING_FROZEN:
++ /* Update our root-domain */
++ grq_lock_irqsave(&flags);
++ if (rq->rd) {
++ BUG_ON(!cpumask_test_cpu(cpu, rq->rd->span));
++ set_rq_offline(rq);
++ }
++ grq_unlock_irqrestore(&flags);
++ break;
++#endif
++ }
++ return NOTIFY_OK;
++}
++
++/*
++ * Register at high priority so that task migration (migrate_all_tasks)
++ * happens before everything else. This has to be lower priority than
++ * the notifier in the perf_counter subsystem, though.
++ */
++static struct notifier_block __cpuinitdata migration_notifier = {
++ .notifier_call = migration_call,
++ .priority = CPU_PRI_MIGRATION,
++};
++
++static int __cpuinit sched_cpu_active(struct notifier_block *nfb,
++ unsigned long action, void *hcpu)
++{
++ switch (action & ~CPU_TASKS_FROZEN) {
++ case CPU_ONLINE:
++ case CPU_DOWN_FAILED:
++ set_cpu_active((long)hcpu, true);
++ return NOTIFY_OK;
++ default:
++ return NOTIFY_DONE;
++ }
++}
++
++static int __cpuinit sched_cpu_inactive(struct notifier_block *nfb,
++ unsigned long action, void *hcpu)
++{
++ switch (action & ~CPU_TASKS_FROZEN) {
++ case CPU_DOWN_PREPARE:
++ set_cpu_active((long)hcpu, false);
++ return NOTIFY_OK;
++ default:
++ return NOTIFY_DONE;
++ }
++}
++
++int __init migration_init(void)
++{
++ void *cpu = (void *)(long)smp_processor_id();
++ int err;
++
++ /* Initialise migration for the boot CPU */
++ err = migration_call(&migration_notifier, CPU_UP_PREPARE, cpu);
++ BUG_ON(err == NOTIFY_BAD);
++ migration_call(&migration_notifier, CPU_ONLINE, cpu);
++ register_cpu_notifier(&migration_notifier);
++
++ /* Register cpu active notifiers */
++ cpu_notifier(sched_cpu_active, CPU_PRI_SCHED_ACTIVE);
++ cpu_notifier(sched_cpu_inactive, CPU_PRI_SCHED_INACTIVE);
++
++ return 0;
++}
++early_initcall(migration_init);
++#endif
++
++#ifdef CONFIG_SMP
++
++#ifdef CONFIG_SCHED_DEBUG
++
++static __read_mostly int sched_domain_debug_enabled;
++
++static int __init sched_domain_debug_setup(char *str)
++{
++ sched_domain_debug_enabled = 1;
++
++ return 0;
++}
++early_param("sched_debug", sched_domain_debug_setup);
++
++static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level,
++ struct cpumask *groupmask)
++{
++ struct sched_group *group = sd->groups;
++ char str[256];
++
++ cpulist_scnprintf(str, sizeof(str), sched_domain_span(sd));
++ cpumask_clear(groupmask);
++
++ printk(KERN_DEBUG "%*s domain %d: ", level, "", level);
++
++ if (!(sd->flags & SD_LOAD_BALANCE)) {
++ printk("does not load-balance\n");
++ if (sd->parent)
++ printk(KERN_ERR "ERROR: !SD_LOAD_BALANCE domain"
++ " has parent");
++ return -1;
++ }
++
++ printk(KERN_CONT "span %s level %s\n", str, sd->name);
++
++ if (!cpumask_test_cpu(cpu, sched_domain_span(sd))) {
++ printk(KERN_ERR "ERROR: domain->span does not contain "
++ "CPU%d\n", cpu);
++ }
++ if (!cpumask_test_cpu(cpu, sched_group_cpus(group))) {
++ printk(KERN_ERR "ERROR: domain->groups does not contain"
++ " CPU%d\n", cpu);
++ }
++
++ printk(KERN_DEBUG "%*s groups:", level + 1, "");
++ do {
++ if (!group) {
++ printk("\n");
++ printk(KERN_ERR "ERROR: group is NULL\n");
++ break;
++ }
++
++ if (!group->cpu_power) {
++ printk(KERN_CONT "\n");
++ printk(KERN_ERR "ERROR: domain->cpu_power not "
++ "set\n");
++ break;
++ }
++
++ if (!cpumask_weight(sched_group_cpus(group))) {
++ printk(KERN_CONT "\n");
++ printk(KERN_ERR "ERROR: empty group\n");
++ break;
++ }
++
++ if (cpumask_intersects(groupmask, sched_group_cpus(group))) {
++ printk(KERN_CONT "\n");
++ printk(KERN_ERR "ERROR: repeated CPUs\n");
++ break;
++ }
++
++ cpumask_or(groupmask, groupmask, sched_group_cpus(group));
++
++ cpulist_scnprintf(str, sizeof(str), sched_group_cpus(group));
++
++ printk(KERN_CONT " %s", str);
++ if (group->cpu_power != SCHED_LOAD_SCALE) {
++ printk(KERN_CONT " (cpu_power = %d)",
++ group->cpu_power);
++ }
++
++ group = group->next;
++ } while (group != sd->groups);
++ printk(KERN_CONT "\n");
++
++ if (!cpumask_equal(sched_domain_span(sd), groupmask))
++ printk(KERN_ERR "ERROR: groups don't span domain->span\n");
++
++ if (sd->parent &&
++ !cpumask_subset(groupmask, sched_domain_span(sd->parent)))
++ printk(KERN_ERR "ERROR: parent span is not a superset "
++ "of domain->span\n");
++ return 0;
++}
++
++static void sched_domain_debug(struct sched_domain *sd, int cpu)
++{
++ cpumask_var_t groupmask;
++ int level = 0;
++
++ if (!sched_domain_debug_enabled)
++ return;
++
++ if (!sd) {
++ printk(KERN_DEBUG "CPU%d attaching NULL sched-domain.\n", cpu);
++ return;
++ }
++
++ printk(KERN_DEBUG "CPU%d attaching sched-domain:\n", cpu);
++
++ if (!alloc_cpumask_var(&groupmask, GFP_KERNEL)) {
++ printk(KERN_DEBUG "Cannot load-balance (out of memory)\n");
++ return;
++ }
++
++ for (;;) {
++ if (sched_domain_debug_one(sd, cpu, level, groupmask))
++ break;
++ level++;
++ sd = sd->parent;
++ if (!sd)
++ break;
++ }
++ free_cpumask_var(groupmask);
++}
++#else /* !CONFIG_SCHED_DEBUG */
++# define sched_domain_debug(sd, cpu) do { } while (0)
++#endif /* CONFIG_SCHED_DEBUG */
++
++static int sd_degenerate(struct sched_domain *sd)
++{
++ if (cpumask_weight(sched_domain_span(sd)) == 1)
++ return 1;
++
++ /* Following flags need at least 2 groups */
++ if (sd->flags & (SD_LOAD_BALANCE |
++ SD_BALANCE_NEWIDLE |
++ SD_BALANCE_FORK |
++ SD_BALANCE_EXEC |
++ SD_SHARE_CPUPOWER |
++ SD_SHARE_PKG_RESOURCES)) {
++ if (sd->groups != sd->groups->next)
++ return 0;
++ }
++
++ /* Following flags don't use groups */
++ if (sd->flags & (SD_WAKE_AFFINE))
++ return 0;
++
++ return 1;
++}
++
++static int
++sd_parent_degenerate(struct sched_domain *sd, struct sched_domain *parent)
++{
++ unsigned long cflags = sd->flags, pflags = parent->flags;
++
++ if (sd_degenerate(parent))
++ return 1;
++
++ if (!cpumask_equal(sched_domain_span(sd), sched_domain_span(parent)))
++ return 0;
++
++ /* Flags needing groups don't count if only 1 group in parent */
++ if (parent->groups == parent->groups->next) {
++ pflags &= ~(SD_LOAD_BALANCE |
++ SD_BALANCE_NEWIDLE |
++ SD_BALANCE_FORK |
++ SD_BALANCE_EXEC |
++ SD_SHARE_CPUPOWER |
++ SD_SHARE_PKG_RESOURCES);
++ if (nr_node_ids == 1)
++ pflags &= ~SD_SERIALIZE;
++ }
++ if (~cflags & pflags)
++ return 0;
++
++ return 1;
++}
++
++static void free_rootdomain(struct root_domain *rd)
++{
++ synchronize_sched();
++
++ free_cpumask_var(rd->rto_mask);
++ free_cpumask_var(rd->online);
++ free_cpumask_var(rd->span);
++ kfree(rd);
++}
++
++static void rq_attach_root(struct rq *rq, struct root_domain *rd)
++{
++ struct root_domain *old_rd = NULL;
++ unsigned long flags;
++
++ grq_lock_irqsave(&flags);
++
++ if (rq->rd) {
++ old_rd = rq->rd;
++
++ if (cpumask_test_cpu(cpu_of(rq), old_rd->online))
++ set_rq_offline(rq);
++
++ cpumask_clear_cpu(cpu_of(rq), old_rd->span);
++
++ /*
++ * If we dont want to free the old_rt yet then
++ * set old_rd to NULL to skip the freeing later
++ * in this function:
++ */
++ if (!atomic_dec_and_test(&old_rd->refcount))
++ old_rd = NULL;
++ }
++
++ atomic_inc(&rd->refcount);
++ rq->rd = rd;
++
++ cpumask_set_cpu(cpu_of(rq), rd->span);
++ if (cpumask_test_cpu(rq->cpu, cpu_active_mask))
++ set_rq_online(rq);
++
++ grq_unlock_irqrestore(&flags);
++
++ if (old_rd)
++ free_rootdomain(old_rd);
++}
++
++static int init_rootdomain(struct root_domain *rd)
++{
++ memset(rd, 0, sizeof(*rd));
++
++ if (!alloc_cpumask_var(&rd->span, GFP_KERNEL))
++ goto out;
++ if (!alloc_cpumask_var(&rd->online, GFP_KERNEL))
++ goto free_span;
++ if (!alloc_cpumask_var(&rd->rto_mask, GFP_KERNEL))
++ goto free_online;
++
++ if (cpupri_init(&rd->cpupri) != 0)
++ goto free_rto_mask;
++ return 0;
++
++free_rto_mask:
++ free_cpumask_var(rd->rto_mask);
++free_online:
++ free_cpumask_var(rd->online);
++free_span:
++ free_cpumask_var(rd->span);
++out:
++ return -ENOMEM;
++}
++
++static void init_defrootdomain(void)
++{
++ init_rootdomain(&def_root_domain);
++
++ atomic_set(&def_root_domain.refcount, 1);
++}
++
++static struct root_domain *alloc_rootdomain(void)
++{
++ struct root_domain *rd;
++
++ rd = kmalloc(sizeof(*rd), GFP_KERNEL);
++ if (!rd)
++ return NULL;
++
++ if (init_rootdomain(rd) != 0) {
++ kfree(rd);
++ return NULL;
++ }
++
++ return rd;
++}
++
++/*
++ * Attach the domain 'sd' to 'cpu' as its base domain. Callers must
++ * hold the hotplug lock.
++ */
++static void
++cpu_attach_domain(struct sched_domain *sd, struct root_domain *rd, int cpu)
++{
++ struct rq *rq = cpu_rq(cpu);
++ struct sched_domain *tmp;
++
++ for (tmp = sd; tmp; tmp = tmp->parent)
++ tmp->span_weight = cpumask_weight(sched_domain_span(tmp));
++
++ /* Remove the sched domains which do not contribute to scheduling. */
++ for (tmp = sd; tmp; ) {
++ struct sched_domain *parent = tmp->parent;
++ if (!parent)
++ break;
++
++ if (sd_parent_degenerate(tmp, parent)) {
++ tmp->parent = parent->parent;
++ if (parent->parent)
++ parent->parent->child = tmp;
++ } else
++ tmp = tmp->parent;
++ }
++
++ if (sd && sd_degenerate(sd)) {
++ sd = sd->parent;
++ if (sd)
++ sd->child = NULL;
++ }
++
++ sched_domain_debug(sd, cpu);
++
++ rq_attach_root(rq, rd);
++ rcu_assign_pointer(rq->sd, sd);
++}
++
++/* cpus with isolated domains */
++static cpumask_var_t cpu_isolated_map;
++
++/* Setup the mask of cpus configured for isolated domains */
++static int __init isolated_cpu_setup(char *str)
++{
++ alloc_bootmem_cpumask_var(&cpu_isolated_map);
++ cpulist_parse(str, cpu_isolated_map);
++ return 1;
++}
++
++__setup("isolcpus=", isolated_cpu_setup);
++
++/*
++ * init_sched_build_groups takes the cpumask we wish to span, and a pointer
++ * to a function which identifies what group(along with sched group) a CPU
++ * belongs to. The return value of group_fn must be a >= 0 and < nr_cpu_ids
++ * (due to the fact that we keep track of groups covered with a struct cpumask).
++ *
++ * init_sched_build_groups will build a circular linked list of the groups
++ * covered by the given span, and will set each group's ->cpumask correctly,
++ * and ->cpu_power to 0.
++ */
++static void
++init_sched_build_groups(const struct cpumask *span,
++ const struct cpumask *cpu_map,
++ int (*group_fn)(int cpu, const struct cpumask *cpu_map,
++ struct sched_group **sg,
++ struct cpumask *tmpmask),
++ struct cpumask *covered, struct cpumask *tmpmask)
++{
++ struct sched_group *first = NULL, *last = NULL;
++ int i;
++
++ cpumask_clear(covered);
++
++ for_each_cpu(i, span) {
++ struct sched_group *sg;
++ int group = group_fn(i, cpu_map, &sg, tmpmask);
++ int j;
++
++ if (cpumask_test_cpu(i, covered))
++ continue;
++
++ cpumask_clear(sched_group_cpus(sg));
++ sg->cpu_power = 0;
++
++ for_each_cpu(j, span) {
++ if (group_fn(j, cpu_map, NULL, tmpmask) != group)
++ continue;
++
++ cpumask_set_cpu(j, covered);
++ cpumask_set_cpu(j, sched_group_cpus(sg));
++ }
++ if (!first)
++ first = sg;
++ if (last)
++ last->next = sg;
++ last = sg;
++ }
++ last->next = first;
++}
++
++#define SD_NODES_PER_DOMAIN 16
++
++#ifdef CONFIG_NUMA
++
++/**
++ * find_next_best_node - find the next node to include in a sched_domain
++ * @node: node whose sched_domain we're building
++ * @used_nodes: nodes already in the sched_domain
++ *
++ * Find the next node to include in a given scheduling domain. Simply
++ * finds the closest node not already in the @used_nodes map.
++ *
++ * Should use nodemask_t.
++ */
++static int find_next_best_node(int node, nodemask_t *used_nodes)
++{
++ int i, n, val, min_val, best_node = 0;
++
++ min_val = INT_MAX;
++
++ for (i = 0; i < nr_node_ids; i++) {
++ /* Start at @node */
++ n = (node + i) % nr_node_ids;
++
++ if (!nr_cpus_node(n))
++ continue;
++
++ /* Skip already used nodes */
++ if (node_isset(n, *used_nodes))
++ continue;
++
++ /* Simple min distance search */
++ val = node_distance(node, n);
++
++ if (val < min_val) {
++ min_val = val;
++ best_node = n;
++ }
++ }
++
++ node_set(best_node, *used_nodes);
++ return best_node;
++}
++
++/**
++ * sched_domain_node_span - get a cpumask for a node's sched_domain
++ * @node: node whose cpumask we're constructing
++ * @span: resulting cpumask
++ *
++ * Given a node, construct a good cpumask for its sched_domain to span. It
++ * should be one that prevents unnecessary balancing, but also spreads tasks
++ * out optimally.
++ */
++static void sched_domain_node_span(int node, struct cpumask *span)
++{
++ nodemask_t used_nodes;
++ int i;
++
++ cpumask_clear(span);
++ nodes_clear(used_nodes);
++
++ cpumask_or(span, span, cpumask_of_node(node));
++ node_set(node, used_nodes);
++
++ for (i = 1; i < SD_NODES_PER_DOMAIN; i++) {
++ int next_node = find_next_best_node(node, &used_nodes);
++
++ cpumask_or(span, span, cpumask_of_node(next_node));
++ }
++}
++#endif /* CONFIG_NUMA */
++
++int sched_smt_power_savings = 0, sched_mc_power_savings = 0;
++
++/*
++ * The cpus mask in sched_group and sched_domain hangs off the end.
++ *
++ * ( See the the comments in include/linux/sched.h:struct sched_group
++ * and struct sched_domain. )
++ */
++struct static_sched_group {
++ struct sched_group sg;
++ DECLARE_BITMAP(cpus, CONFIG_NR_CPUS);
++};
++
++struct static_sched_domain {
++ struct sched_domain sd;
++ DECLARE_BITMAP(span, CONFIG_NR_CPUS);
++};
++
++struct s_data {
++#ifdef CONFIG_NUMA
++ int sd_allnodes;
++ cpumask_var_t domainspan;
++ cpumask_var_t covered;
++ cpumask_var_t notcovered;
++#endif
++ cpumask_var_t nodemask;
++ cpumask_var_t this_sibling_map;
++ cpumask_var_t this_core_map;
++ cpumask_var_t this_book_map;
++ cpumask_var_t send_covered;
++ cpumask_var_t tmpmask;
++ struct sched_group **sched_group_nodes;
++ struct root_domain *rd;
++};
++
++enum s_alloc {
++ sa_sched_groups = 0,
++ sa_rootdomain,
++ sa_tmpmask,
++ sa_send_covered,
++ sa_this_book_map,
++ sa_this_core_map,
++ sa_this_sibling_map,
++ sa_nodemask,
++ sa_sched_group_nodes,
++#ifdef CONFIG_NUMA
++ sa_notcovered,
++ sa_covered,
++ sa_domainspan,
++#endif
++ sa_none,
++};
++
++/*
++ * SMT sched-domains:
++ */
++#ifdef CONFIG_SCHED_SMT
++static DEFINE_PER_CPU(struct static_sched_domain, cpu_domains);
++static DEFINE_PER_CPU(struct static_sched_group, sched_groups);
++
++static int
++cpu_to_cpu_group(int cpu, const struct cpumask *cpu_map,
++ struct sched_group **sg, struct cpumask *unused)
++{
++ if (sg)
++ *sg = &per_cpu(sched_groups, cpu).sg;
++ return cpu;
++}
++#endif /* CONFIG_SCHED_SMT */
++
++/*
++ * multi-core sched-domains:
++ */
++#ifdef CONFIG_SCHED_MC
++static DEFINE_PER_CPU(struct static_sched_domain, core_domains);
++static DEFINE_PER_CPU(struct static_sched_group, sched_group_core);
++
++static int
++cpu_to_core_group(int cpu, const struct cpumask *cpu_map,
++ struct sched_group **sg, struct cpumask *mask)
++{
++ int group;
++#ifdef CONFIG_SCHED_SMT
++ cpumask_and(mask, topology_thread_cpumask(cpu), cpu_map);
++ group = cpumask_first(mask);
++#else
++ group = cpu;
++#endif
++ if (sg)
++ *sg = &per_cpu(sched_group_core, group).sg;
++ return group;
++}
++#endif /* CONFIG_SCHED_MC */
++
++/*
++ * book sched-domains:
++ */
++#ifdef CONFIG_SCHED_BOOK
++static DEFINE_PER_CPU(struct static_sched_domain, book_domains);
++static DEFINE_PER_CPU(struct static_sched_group, sched_group_book);
++
++static int
++cpu_to_book_group(int cpu, const struct cpumask *cpu_map,
++ struct sched_group **sg, struct cpumask *mask)
++{
++ int group = cpu;
++#ifdef CONFIG_SCHED_MC
++ cpumask_and(mask, cpu_coregroup_mask(cpu), cpu_map);
++ group = cpumask_first(mask);
++#elif defined(CONFIG_SCHED_SMT)
++ cpumask_and(mask, topology_thread_cpumask(cpu), cpu_map);
++ group = cpumask_first(mask);
++#endif
++ if (sg)
++ *sg = &per_cpu(sched_group_book, group).sg;
++ return group;
++}
++#endif /* CONFIG_SCHED_BOOK */
++
++static DEFINE_PER_CPU(struct static_sched_domain, phys_domains);
++static DEFINE_PER_CPU(struct static_sched_group, sched_group_phys);
++
++static int
++cpu_to_phys_group(int cpu, const struct cpumask *cpu_map,
++ struct sched_group **sg, struct cpumask *mask)
++{
++ int group;
++#ifdef CONFIG_SCHED_BOOK
++ cpumask_and(mask, cpu_book_mask(cpu), cpu_map);
++ group = cpumask_first(mask);
++#elif defined(CONFIG_SCHED_MC)
++ cpumask_and(mask, cpu_coregroup_mask(cpu), cpu_map);
++ group = cpumask_first(mask);
++#elif defined(CONFIG_SCHED_SMT)
++ cpumask_and(mask, topology_thread_cpumask(cpu), cpu_map);
++ group = cpumask_first(mask);
++#else
++ group = cpu;
++#endif
++ if (sg)
++ *sg = &per_cpu(sched_group_phys, group).sg;
++ return group;
++}
++
++/**
++ * group_first_cpu - Returns the first cpu in the cpumask of a sched_group.
++ * @group: The group whose first cpu is to be returned.
++ */
++static inline unsigned int group_first_cpu(struct sched_group *group)
++{
++ return cpumask_first(sched_group_cpus(group));
++}
++
++#ifdef CONFIG_NUMA
++/*
++ * The init_sched_build_groups can't handle what we want to do with node
++ * groups, so roll our own. Now each node has its own list of groups which
++ * gets dynamically allocated.
++ */
++static DEFINE_PER_CPU(struct static_sched_domain, node_domains);
++static struct sched_group ***sched_group_nodes_bycpu;
++
++static DEFINE_PER_CPU(struct static_sched_domain, allnodes_domains);
++static DEFINE_PER_CPU(struct static_sched_group, sched_group_allnodes);
++
++static int cpu_to_allnodes_group(int cpu, const struct cpumask *cpu_map,
++ struct sched_group **sg,
++ struct cpumask *nodemask)
++{
++ int group;
++
++ cpumask_and(nodemask, cpumask_of_node(cpu_to_node(cpu)), cpu_map);
++ group = cpumask_first(nodemask);
++
++ if (sg)
++ *sg = &per_cpu(sched_group_allnodes, group).sg;
++ return group;
++}
++
++static void init_numa_sched_groups_power(struct sched_group *group_head)
++{
++ struct sched_group *sg = group_head;
++ int j;
++
++ if (!sg)
++ return;
++ do {
++ for_each_cpu(j, sched_group_cpus(sg)) {
++ struct sched_domain *sd;
++
++ sd = &per_cpu(phys_domains, j).sd;
++ if (j != group_first_cpu(sd->groups)) {
++ /*
++ * Only add "power" once for each
++ * physical package.
++ */
++ continue;
++ }
++
++ sg->cpu_power += sd->groups->cpu_power;
++ }
++ sg = sg->next;
++ } while (sg != group_head);
++}
++
++static int build_numa_sched_groups(struct s_data *d,
++ const struct cpumask *cpu_map, int num)
++{
++ struct sched_domain *sd;
++ struct sched_group *sg, *prev;
++ int n, j;
++
++ cpumask_clear(d->covered);
++ cpumask_and(d->nodemask, cpumask_of_node(num), cpu_map);
++ if (cpumask_empty(d->nodemask)) {
++ d->sched_group_nodes[num] = NULL;
++ goto out;
++ }
++
++ sched_domain_node_span(num, d->domainspan);
++ cpumask_and(d->domainspan, d->domainspan, cpu_map);
++
++ sg = kmalloc_node(sizeof(struct sched_group) + cpumask_size(),
++ GFP_KERNEL, num);
++ if (!sg) {
++ printk(KERN_WARNING "Can not alloc domain group for node %d\n",
++ num);
++ return -ENOMEM;
++ }
++ d->sched_group_nodes[num] = sg;
++
++ for_each_cpu(j, d->nodemask) {
++ sd = &per_cpu(node_domains, j).sd;
++ sd->groups = sg;
++ }
++
++ sg->cpu_power = 0;
++ cpumask_copy(sched_group_cpus(sg), d->nodemask);
++ sg->next = sg;
++ cpumask_or(d->covered, d->covered, d->nodemask);
++
++ prev = sg;
++ for (j = 0; j < nr_node_ids; j++) {
++ n = (num + j) % nr_node_ids;
++ cpumask_complement(d->notcovered, d->covered);
++ cpumask_and(d->tmpmask, d->notcovered, cpu_map);
++ cpumask_and(d->tmpmask, d->tmpmask, d->domainspan);
++ if (cpumask_empty(d->tmpmask))
++ break;
++ cpumask_and(d->tmpmask, d->tmpmask, cpumask_of_node(n));
++ if (cpumask_empty(d->tmpmask))
++ continue;
++ sg = kmalloc_node(sizeof(struct sched_group) + cpumask_size(),
++ GFP_KERNEL, num);
++ if (!sg) {
++ printk(KERN_WARNING
++ "Can not alloc domain group for node %d\n", j);
++ return -ENOMEM;
++ }
++ sg->cpu_power = 0;
++ cpumask_copy(sched_group_cpus(sg), d->tmpmask);
++ sg->next = prev->next;
++ cpumask_or(d->covered, d->covered, d->tmpmask);
++ prev->next = sg;
++ prev = sg;
++ }
++out:
++ return 0;
++}
++#endif /* CONFIG_NUMA */
++
++#ifdef CONFIG_NUMA
++/* Free memory allocated for various sched_group structures */
++static void free_sched_groups(const struct cpumask *cpu_map,
++ struct cpumask *nodemask)
++{
++ int cpu, i;
++
++ for_each_cpu(cpu, cpu_map) {
++ struct sched_group **sched_group_nodes
++ = sched_group_nodes_bycpu[cpu];
++
++ if (!sched_group_nodes)
++ continue;
++
++ for (i = 0; i < nr_node_ids; i++) {
++ struct sched_group *oldsg, *sg = sched_group_nodes[i];
++
++ cpumask_and(nodemask, cpumask_of_node(i), cpu_map);
++ if (cpumask_empty(nodemask))
++ continue;
++
++ if (sg == NULL)
++ continue;
++ sg = sg->next;
++next_sg:
++ oldsg = sg;
++ sg = sg->next;
++ kfree(oldsg);
++ if (oldsg != sched_group_nodes[i])
++ goto next_sg;
++ }
++ kfree(sched_group_nodes);
++ sched_group_nodes_bycpu[cpu] = NULL;
++ }
++}
++#else /* !CONFIG_NUMA */
++static void free_sched_groups(const struct cpumask *cpu_map,
++ struct cpumask *nodemask)
++{
++}
++#endif /* CONFIG_NUMA */
++
++/*
++ * Initialise sched groups cpu_power.
++ *
++ * cpu_power indicates the capacity of sched group, which is used while
++ * distributing the load between different sched groups in a sched domain.
++ * Typically cpu_power for all the groups in a sched domain will be same unless
++ * there are asymmetries in the topology. If there are asymmetries, group
++ * having more cpu_power will pickup more load compared to the group having
++ * less cpu_power.
++ *
++ * cpu_power will be a multiple of SCHED_LOAD_SCALE. This multiple represents
++ * the maximum number of tasks a group can handle in the presence of other idle
++ * or lightly loaded groups in the same sched domain.
++ */
++static void init_sched_groups_power(int cpu, struct sched_domain *sd)
++{
++ struct sched_domain *child;
++ struct sched_group *group;
++ long power;
++ int weight;
++
++ WARN_ON(!sd || !sd->groups);
++
++ if (cpu != group_first_cpu(sd->groups))
++ return;
++
++ sd->groups->group_weight = cpumask_weight(sched_group_cpus(sd->groups));
++
++ child = sd->child;
++
++ sd->groups->cpu_power = 0;
++
++ if (!child) {
++ power = SCHED_LOAD_SCALE;
++ weight = cpumask_weight(sched_domain_span(sd));
++ /*
++ * SMT siblings share the power of a single core.
++ * Usually multiple threads get a better yield out of
++ * that one core than a single thread would have,
++ * reflect that in sd->smt_gain.
++ */
++ if ((sd->flags & SD_SHARE_CPUPOWER) && weight > 1) {
++ power *= sd->smt_gain;
++ power /= weight;
++ power >>= SCHED_LOAD_SHIFT;
++ }
++ sd->groups->cpu_power += power;
++ return;
++ }
++
++ /*
++ * Add cpu_power of each child group to this groups cpu_power
++ */
++ group = child->groups;
++ do {
++ sd->groups->cpu_power += group->cpu_power;
++ group = group->next;
++ } while (group != child->groups);
++}
++
++/*
++ * Initialisers for schedule domains
++ * Non-inlined to reduce accumulated stack pressure in build_sched_domains()
++ */
++
++#ifdef CONFIG_SCHED_DEBUG
++# define SD_INIT_NAME(sd, type) sd->name = #type
++#else
++# define SD_INIT_NAME(sd, type) do { } while (0)
++#endif
++
++#define SD_INIT(sd, type) sd_init_##type(sd)
++
++#define SD_INIT_FUNC(type) \
++static noinline void sd_init_##type(struct sched_domain *sd) \
++{ \
++ memset(sd, 0, sizeof(*sd)); \
++ *sd = SD_##type##_INIT; \
++ sd->level = SD_LV_##type; \
++ SD_INIT_NAME(sd, type); \
++}
++
++SD_INIT_FUNC(CPU)
++#ifdef CONFIG_NUMA
++ SD_INIT_FUNC(ALLNODES)
++ SD_INIT_FUNC(NODE)
++#endif
++#ifdef CONFIG_SCHED_SMT
++ SD_INIT_FUNC(SIBLING)
++#endif
++#ifdef CONFIG_SCHED_MC
++ SD_INIT_FUNC(MC)
++#endif
++#ifdef CONFIG_SCHED_BOOK
++ SD_INIT_FUNC(BOOK)
++#endif
++
++static int default_relax_domain_level = -1;
++
++static int __init setup_relax_domain_level(char *str)
++{
++ unsigned long val;
++
++ val = simple_strtoul(str, NULL, 0);
++ if (val < SD_LV_MAX)
++ default_relax_domain_level = val;
++
++ return 1;
++}
++__setup("relax_domain_level=", setup_relax_domain_level);
++
++static void set_domain_attribute(struct sched_domain *sd,
++ struct sched_domain_attr *attr)
++{
++ int request;
++
++ if (!attr || attr->relax_domain_level < 0) {
++ if (default_relax_domain_level < 0)
++ return;
++ else
++ request = default_relax_domain_level;
++ } else
++ request = attr->relax_domain_level;
++ if (request < sd->level) {
++ /* turn off idle balance on this domain */
++ sd->flags &= ~(SD_BALANCE_WAKE|SD_BALANCE_NEWIDLE);
++ } else {
++ /* turn on idle balance on this domain */
++ sd->flags |= (SD_BALANCE_WAKE|SD_BALANCE_NEWIDLE);
++ }
++}
++
++static void __free_domain_allocs(struct s_data *d, enum s_alloc what,
++ const struct cpumask *cpu_map)
++{
++ switch (what) {
++ case sa_sched_groups:
++ free_sched_groups(cpu_map, d->tmpmask); /* fall through */
++ d->sched_group_nodes = NULL;
++ case sa_rootdomain:
++ free_rootdomain(d->rd); /* fall through */
++ case sa_tmpmask:
++ free_cpumask_var(d->tmpmask); /* fall through */
++ case sa_send_covered:
++ free_cpumask_var(d->send_covered); /* fall through */
++ case sa_this_book_map:
++ free_cpumask_var(d->this_book_map); /* fall through */
++ case sa_this_core_map:
++ free_cpumask_var(d->this_core_map); /* fall through */
++ case sa_this_sibling_map:
++ free_cpumask_var(d->this_sibling_map); /* fall through */
++ case sa_nodemask:
++ free_cpumask_var(d->nodemask); /* fall through */
++ case sa_sched_group_nodes:
++#ifdef CONFIG_NUMA
++ kfree(d->sched_group_nodes); /* fall through */
++ case sa_notcovered:
++ free_cpumask_var(d->notcovered); /* fall through */
++ case sa_covered:
++ free_cpumask_var(d->covered); /* fall through */
++ case sa_domainspan:
++ free_cpumask_var(d->domainspan); /* fall through */
++#endif
++ case sa_none:
++ break;
++ }
++}
++
++static enum s_alloc __visit_domain_allocation_hell(struct s_data *d,
++ const struct cpumask *cpu_map)
++{
++#ifdef CONFIG_NUMA
++ if (!alloc_cpumask_var(&d->domainspan, GFP_KERNEL))
++ return sa_none;
++ if (!alloc_cpumask_var(&d->covered, GFP_KERNEL))
++ return sa_domainspan;
++ if (!alloc_cpumask_var(&d->notcovered, GFP_KERNEL))
++ return sa_covered;
++ /* Allocate the per-node list of sched groups */
++ d->sched_group_nodes = kcalloc(nr_node_ids,
++ sizeof(struct sched_group *), GFP_KERNEL);
++ if (!d->sched_group_nodes) {
++ printk(KERN_WARNING "Can not alloc sched group node list\n");
++ return sa_notcovered;
++ }
++ sched_group_nodes_bycpu[cpumask_first(cpu_map)] = d->sched_group_nodes;
++#endif
++ if (!alloc_cpumask_var(&d->nodemask, GFP_KERNEL))
++ return sa_sched_group_nodes;
++ if (!alloc_cpumask_var(&d->this_sibling_map, GFP_KERNEL))
++ return sa_nodemask;
++ if (!alloc_cpumask_var(&d->this_core_map, GFP_KERNEL))
++ return sa_this_sibling_map;
++ if (!alloc_cpumask_var(&d->this_book_map, GFP_KERNEL))
++ return sa_this_core_map;
++ if (!alloc_cpumask_var(&d->send_covered, GFP_KERNEL))
++ return sa_this_book_map;
++ if (!alloc_cpumask_var(&d->tmpmask, GFP_KERNEL))
++ return sa_send_covered;
++ d->rd = alloc_rootdomain();
++ if (!d->rd) {
++ printk(KERN_WARNING "Cannot alloc root domain\n");
++ return sa_tmpmask;
++ }
++ return sa_rootdomain;
++}
++
++static struct sched_domain *__build_numa_sched_domains(struct s_data *d,
++ const struct cpumask *cpu_map, struct sched_domain_attr *attr, int i)
++{
++ struct sched_domain *sd = NULL;
++#ifdef CONFIG_NUMA
++ struct sched_domain *parent;
++
++ d->sd_allnodes = 0;
++ if (cpumask_weight(cpu_map) >
++ SD_NODES_PER_DOMAIN * cpumask_weight(d->nodemask)) {
++ sd = &per_cpu(allnodes_domains, i).sd;
++ SD_INIT(sd, ALLNODES);
++ set_domain_attribute(sd, attr);
++ cpumask_copy(sched_domain_span(sd), cpu_map);
++ cpu_to_allnodes_group(i, cpu_map, &sd->groups, d->tmpmask);
++ d->sd_allnodes = 1;
++ }
++ parent = sd;
++
++ sd = &per_cpu(node_domains, i).sd;
++ SD_INIT(sd, NODE);
++ set_domain_attribute(sd, attr);
++ sched_domain_node_span(cpu_to_node(i), sched_domain_span(sd));
++ sd->parent = parent;
++ if (parent)
++ parent->child = sd;
++ cpumask_and(sched_domain_span(sd), sched_domain_span(sd), cpu_map);
++#endif
++ return sd;
++}
++
++static struct sched_domain *__build_cpu_sched_domain(struct s_data *d,
++ const struct cpumask *cpu_map, struct sched_domain_attr *attr,
++ struct sched_domain *parent, int i)
++{
++ struct sched_domain *sd;
++ sd = &per_cpu(phys_domains, i).sd;
++ SD_INIT(sd, CPU);
++ set_domain_attribute(sd, attr);
++ cpumask_copy(sched_domain_span(sd), d->nodemask);
++ sd->parent = parent;
++ if (parent)
++ parent->child = sd;
++ cpu_to_phys_group(i, cpu_map, &sd->groups, d->tmpmask);
++ return sd;
++}
++
++static struct sched_domain *__build_book_sched_domain(struct s_data *d,
++ const struct cpumask *cpu_map, struct sched_domain_attr *attr,
++ struct sched_domain *parent, int i)
++{
++ struct sched_domain *sd = parent;
++#ifdef CONFIG_SCHED_BOOK
++ sd = &per_cpu(book_domains, i).sd;
++ SD_INIT(sd, BOOK);
++ set_domain_attribute(sd, attr);
++ cpumask_and(sched_domain_span(sd), cpu_map, cpu_book_mask(i));
++ sd->parent = parent;
++ parent->child = sd;
++ cpu_to_book_group(i, cpu_map, &sd->groups, d->tmpmask);
++#endif
++ return sd;
++}
++
++static struct sched_domain *__build_mc_sched_domain(struct s_data *d,
++ const struct cpumask *cpu_map, struct sched_domain_attr *attr,
++ struct sched_domain *parent, int i)
++{
++ struct sched_domain *sd = parent;
++#ifdef CONFIG_SCHED_MC
++ sd = &per_cpu(core_domains, i).sd;
++ SD_INIT(sd, MC);
++ set_domain_attribute(sd, attr);
++ cpumask_and(sched_domain_span(sd), cpu_map, cpu_coregroup_mask(i));
++ sd->parent = parent;
++ parent->child = sd;
++ cpu_to_core_group(i, cpu_map, &sd->groups, d->tmpmask);
++#endif
++ return sd;
++}
++
++static struct sched_domain *__build_smt_sched_domain(struct s_data *d,
++ const struct cpumask *cpu_map, struct sched_domain_attr *attr,
++ struct sched_domain *parent, int i)
++{
++ struct sched_domain *sd = parent;
++#ifdef CONFIG_SCHED_SMT
++ sd = &per_cpu(cpu_domains, i).sd;
++ SD_INIT(sd, SIBLING);
++ set_domain_attribute(sd, attr);
++ cpumask_and(sched_domain_span(sd), cpu_map, topology_thread_cpumask(i));
++ sd->parent = parent;
++ parent->child = sd;
++ cpu_to_cpu_group(i, cpu_map, &sd->groups, d->tmpmask);
++#endif
++ return sd;
++}
++
++static void build_sched_groups(struct s_data *d, enum sched_domain_level l,
++ const struct cpumask *cpu_map, int cpu)
++{
++ switch (l) {
++#ifdef CONFIG_SCHED_SMT
++ case SD_LV_SIBLING: /* set up CPU (sibling) groups */
++ cpumask_and(d->this_sibling_map, cpu_map,
++ topology_thread_cpumask(cpu));
++ if (cpu == cpumask_first(d->this_sibling_map))
++ init_sched_build_groups(d->this_sibling_map, cpu_map,
++ &cpu_to_cpu_group,
++ d->send_covered, d->tmpmask);
++ break;
++#endif
++#ifdef CONFIG_SCHED_MC
++ case SD_LV_MC: /* set up multi-core groups */
++ cpumask_and(d->this_core_map, cpu_map, cpu_coregroup_mask(cpu));
++ if (cpu == cpumask_first(d->this_core_map))
++ init_sched_build_groups(d->this_core_map, cpu_map,
++ &cpu_to_core_group,
++ d->send_covered, d->tmpmask);
++ break;
++#endif
++#ifdef CONFIG_SCHED_BOOK
++ case SD_LV_BOOK: /* set up book groups */
++ cpumask_and(d->this_book_map, cpu_map, cpu_book_mask(cpu));
++ if (cpu == cpumask_first(d->this_book_map))
++ init_sched_build_groups(d->this_book_map, cpu_map,
++ &cpu_to_book_group,
++ d->send_covered, d->tmpmask);
++ break;
++#endif
++ case SD_LV_CPU: /* set up physical groups */
++ cpumask_and(d->nodemask, cpumask_of_node(cpu), cpu_map);
++ if (!cpumask_empty(d->nodemask))
++ init_sched_build_groups(d->nodemask, cpu_map,
++ &cpu_to_phys_group,
++ d->send_covered, d->tmpmask);
++ break;
++#ifdef CONFIG_NUMA
++ case SD_LV_ALLNODES:
++ init_sched_build_groups(cpu_map, cpu_map, &cpu_to_allnodes_group,
++ d->send_covered, d->tmpmask);
++ break;
++#endif
++ default:
++ break;
++ }
++}
++
++/*
++ * Build sched domains for a given set of cpus and attach the sched domains
++ * to the individual cpus
++ */
++static int __build_sched_domains(const struct cpumask *cpu_map,
++ struct sched_domain_attr *attr)
++{
++ enum s_alloc alloc_state = sa_none;
++ struct s_data d;
++ struct sched_domain *sd;
++ int i;
++#ifdef CONFIG_NUMA
++ d.sd_allnodes = 0;
++#endif
++
++ alloc_state = __visit_domain_allocation_hell(&d, cpu_map);
++ if (alloc_state != sa_rootdomain)
++ goto error;
++ alloc_state = sa_sched_groups;
++
++ /*
++ * Set up domains for cpus specified by the cpu_map.
++ */
++ for_each_cpu(i, cpu_map) {
++ cpumask_and(d.nodemask, cpumask_of_node(cpu_to_node(i)),
++ cpu_map);
++
++ sd = __build_numa_sched_domains(&d, cpu_map, attr, i);
++ sd = __build_cpu_sched_domain(&d, cpu_map, attr, sd, i);
++ sd = __build_book_sched_domain(&d, cpu_map, attr, sd, i);
++ sd = __build_mc_sched_domain(&d, cpu_map, attr, sd, i);
++ sd = __build_smt_sched_domain(&d, cpu_map, attr, sd, i);
++ }
++
++ for_each_cpu(i, cpu_map) {
++ build_sched_groups(&d, SD_LV_SIBLING, cpu_map, i);
++ build_sched_groups(&d, SD_LV_BOOK, cpu_map, i);
++ build_sched_groups(&d, SD_LV_MC, cpu_map, i);
++ }
++
++ /* Set up physical groups */
++ for (i = 0; i < nr_node_ids; i++)
++ build_sched_groups(&d, SD_LV_CPU, cpu_map, i);
++
++#ifdef CONFIG_NUMA
++ /* Set up node groups */
++ if (d.sd_allnodes)
++ build_sched_groups(&d, SD_LV_ALLNODES, cpu_map, 0);
++
++ for (i = 0; i < nr_node_ids; i++)
++ if (build_numa_sched_groups(&d, cpu_map, i))
++ goto error;
++#endif
++
++ /* Calculate CPU power for physical packages and nodes */
++#ifdef CONFIG_SCHED_SMT
++ for_each_cpu(i, cpu_map) {
++ sd = &per_cpu(cpu_domains, i).sd;
++ init_sched_groups_power(i, sd);
++ }
++#endif
++#ifdef CONFIG_SCHED_MC
++ for_each_cpu(i, cpu_map) {
++ sd = &per_cpu(core_domains, i).sd;
++ init_sched_groups_power(i, sd);
++ }
++#endif
++#ifdef CONFIG_SCHED_BOOK
++ for_each_cpu(i, cpu_map) {
++ sd = &per_cpu(book_domains, i).sd;
++ init_sched_groups_power(i, sd);
++ }
++#endif
++
++ for_each_cpu(i, cpu_map) {
++ sd = &per_cpu(phys_domains, i).sd;
++ init_sched_groups_power(i, sd);
++ }
++
++#ifdef CONFIG_NUMA
++ for (i = 0; i < nr_node_ids; i++)
++ init_numa_sched_groups_power(d.sched_group_nodes[i]);
++
++ if (d.sd_allnodes) {
++ struct sched_group *sg;
++
++ cpu_to_allnodes_group(cpumask_first(cpu_map), cpu_map, &sg,
++ d.tmpmask);
++ init_numa_sched_groups_power(sg);
++ }
++#endif
++
++ /* Attach the domains */
++ for_each_cpu(i, cpu_map) {
++#ifdef CONFIG_SCHED_SMT
++ sd = &per_cpu(cpu_domains, i).sd;
++#elif defined(CONFIG_SCHED_MC)
++ sd = &per_cpu(core_domains, i).sd;
++#elif defined(CONFIG_SCHED_BOOK)
++ sd = &per_cpu(book_domains, i).sd;
++#else
++ sd = &per_cpu(phys_domains, i).sd;
++#endif
++ cpu_attach_domain(sd, d.rd, i);
++ }
++
++ d.sched_group_nodes = NULL; /* don't free this we still need it */
++ __free_domain_allocs(&d, sa_tmpmask, cpu_map);
++ return 0;
++
++error:
++ __free_domain_allocs(&d, alloc_state, cpu_map);
++ return -ENOMEM;
++}
++
++static int build_sched_domains(const struct cpumask *cpu_map)
++{
++ return __build_sched_domains(cpu_map, NULL);
++}
++
++static cpumask_var_t *doms_cur; /* current sched domains */
++static int ndoms_cur; /* number of sched domains in 'doms_cur' */
++static struct sched_domain_attr *dattr_cur;
++ /* attribues of custom domains in 'doms_cur' */
++
++/*
++ * Special case: If a kmalloc of a doms_cur partition (array of
++ * cpumask) fails, then fallback to a single sched domain,
++ * as determined by the single cpumask fallback_doms.
++ */
++static cpumask_var_t fallback_doms;
++
++/*
++ * arch_update_cpu_topology lets virtualised architectures update the
++ * cpu core maps. It is supposed to return 1 if the topology changed
++ * or 0 if it stayed the same.
++ */
++int __attribute__((weak)) arch_update_cpu_topology(void)
++{
++ return 0;
++}
++
++cpumask_var_t *alloc_sched_domains(unsigned int ndoms)
++{
++ int i;
++ cpumask_var_t *doms;
++
++ doms = kmalloc(sizeof(*doms) * ndoms, GFP_KERNEL);
++ if (!doms)
++ return NULL;
++ for (i = 0; i < ndoms; i++) {
++ if (!alloc_cpumask_var(&doms[i], GFP_KERNEL)) {
++ free_sched_domains(doms, i);
++ return NULL;
++ }
++ }
++ return doms;
++}
++
++void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms)
++{
++ unsigned int i;
++ for (i = 0; i < ndoms; i++)
++ free_cpumask_var(doms[i]);
++ kfree(doms);
++}
++
++/*
++ * Set up scheduler domains and groups. Callers must hold the hotplug lock.
++ * For now this just excludes isolated cpus, but could be used to
++ * exclude other special cases in the future.
++ */
++static int arch_init_sched_domains(const struct cpumask *cpu_map)
++{
++ int err;
++
++ arch_update_cpu_topology();
++ ndoms_cur = 1;
++ doms_cur = alloc_sched_domains(ndoms_cur);
++ if (!doms_cur)
++ doms_cur = &fallback_doms;
++ cpumask_andnot(doms_cur[0], cpu_map, cpu_isolated_map);
++ dattr_cur = NULL;
++ err = build_sched_domains(doms_cur[0]);
++ register_sched_domain_sysctl();
++
++ return err;
++}
++
++static void arch_destroy_sched_domains(const struct cpumask *cpu_map,
++ struct cpumask *tmpmask)
++{
++ free_sched_groups(cpu_map, tmpmask);
++}
++
++/*
++ * Detach sched domains from a group of cpus specified in cpu_map
++ * These cpus will now be attached to the NULL domain
++ */
++static void detach_destroy_domains(const struct cpumask *cpu_map)
++{
++ /* Save because hotplug lock held. */
++ static DECLARE_BITMAP(tmpmask, CONFIG_NR_CPUS);
++ int i;
++
++ for_each_cpu(i, cpu_map)
++ cpu_attach_domain(NULL, &def_root_domain, i);
++ synchronize_sched();
++ arch_destroy_sched_domains(cpu_map, to_cpumask(tmpmask));
++}
++
++/* handle null as "default" */
++static int dattrs_equal(struct sched_domain_attr *cur, int idx_cur,
++ struct sched_domain_attr *new, int idx_new)
++{
++ struct sched_domain_attr tmp;
++
++ /* fast path */
++ if (!new && !cur)
++ return 1;
++
++ tmp = SD_ATTR_INIT;
++ return !memcmp(cur ? (cur + idx_cur) : &tmp,
++ new ? (new + idx_new) : &tmp,
++ sizeof(struct sched_domain_attr));
++}
++
++/*
++ * Partition sched domains as specified by the 'ndoms_new'
++ * cpumasks in the array doms_new[] of cpumasks. This compares
++ * doms_new[] to the current sched domain partitioning, doms_cur[].
++ * It destroys each deleted domain and builds each new domain.
++ *
++ * 'doms_new' is an array of cpumask_var_t's of length 'ndoms_new'.
++ * The masks don't intersect (don't overlap.) We should setup one
++ * sched domain for each mask. CPUs not in any of the cpumasks will
++ * not be load balanced. If the same cpumask appears both in the
++ * current 'doms_cur' domains and in the new 'doms_new', we can leave
++ * it as it is.
++ *
++ * The passed in 'doms_new' should be allocated using
++ * alloc_sched_domains. This routine takes ownership of it and will
++ * free_sched_domains it when done with it. If the caller failed the
++ * alloc call, then it can pass in doms_new == NULL && ndoms_new == 1,
++ * and partition_sched_domains() will fallback to the single partition
++ * 'fallback_doms', it also forces the domains to be rebuilt.
++ *
++ * If doms_new == NULL it will be replaced with cpu_online_mask.
++ * ndoms_new == 0 is a special case for destroying existing domains,
++ * and it will not create the default domain.
++ *
++ * Call with hotplug lock held
++ */
++void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
++ struct sched_domain_attr *dattr_new)
++{
++ int i, j, n;
++ int new_topology;
++
++ mutex_lock(&sched_domains_mutex);
++
++ /* always unregister in case we don't destroy any domains */
++ unregister_sched_domain_sysctl();
++
++ /* Let architecture update cpu core mappings. */
++ new_topology = arch_update_cpu_topology();
++
++ n = doms_new ? ndoms_new : 0;
++
++ /* Destroy deleted domains */
++ for (i = 0; i < ndoms_cur; i++) {
++ for (j = 0; j < n && !new_topology; j++) {
++ if (cpumask_equal(doms_cur[i], doms_new[j])
++ && dattrs_equal(dattr_cur, i, dattr_new, j))
++ goto match1;
++ }
++ /* no match - a current sched domain not in new doms_new[] */
++ detach_destroy_domains(doms_cur[i]);
++match1:
++ ;
++ }
++
++ if (doms_new == NULL) {
++ ndoms_cur = 0;
++ doms_new = &fallback_doms;
++ cpumask_andnot(doms_new[0], cpu_active_mask, cpu_isolated_map);
++ WARN_ON_ONCE(dattr_new);
++ }
++
++ /* Build new domains */
++ for (i = 0; i < ndoms_new; i++) {
++ for (j = 0; j < ndoms_cur && !new_topology; j++) {
++ if (cpumask_equal(doms_new[i], doms_cur[j])
++ && dattrs_equal(dattr_new, i, dattr_cur, j))
++ goto match2;
++ }
++ /* no match - add a new doms_new */
++ __build_sched_domains(doms_new[i],
++ dattr_new ? dattr_new + i : NULL);
++match2:
++ ;
++ }
++
++ /* Remember the new sched domains */
++ if (doms_cur != &fallback_doms)
++ free_sched_domains(doms_cur, ndoms_cur);
++ kfree(dattr_cur); /* kfree(NULL) is safe */
++ doms_cur = doms_new;
++ dattr_cur = dattr_new;
++ ndoms_cur = ndoms_new;
++
++ register_sched_domain_sysctl();
++
++ mutex_unlock(&sched_domains_mutex);
++}
++
++#if defined(CONFIG_SCHED_MC) || defined(CONFIG_SCHED_SMT)
++static void arch_reinit_sched_domains(void)
++{
++ get_online_cpus();
++
++ /* Destroy domains first to force the rebuild */
++ partition_sched_domains(0, NULL, NULL);
++
++ rebuild_sched_domains();
++ put_online_cpus();
++}
++
++static ssize_t sched_power_savings_store(const char *buf, size_t count, int smt)
++{
++ unsigned int level = 0;
++
++ if (sscanf(buf, "%u", &level) != 1)
++ return -EINVAL;
++
++ /*
++ * level is always be positive so don't check for
++ * level < POWERSAVINGS_BALANCE_NONE which is 0
++ * What happens on 0 or 1 byte write,
++ * need to check for count as well?
++ */
++
++ if (level >= MAX_POWERSAVINGS_BALANCE_LEVELS)
++ return -EINVAL;
++
++ if (smt)
++ sched_smt_power_savings = level;
++ else
++ sched_mc_power_savings = level;
++
++ arch_reinit_sched_domains();
++
++ return count;
++}
++
++#ifdef CONFIG_SCHED_MC
++static ssize_t sched_mc_power_savings_show(struct sysdev_class *class,
++ struct sysdev_class_attribute *attr,
++ char *page)
++{
++ return sprintf(page, "%u\n", sched_mc_power_savings);
++}
++static ssize_t sched_mc_power_savings_store(struct sysdev_class *class,
++ struct sysdev_class_attribute *attr,
++ const char *buf, size_t count)
++{
++ return sched_power_savings_store(buf, count, 0);
++}
++static SYSDEV_CLASS_ATTR(sched_mc_power_savings, 0644,
++ sched_mc_power_savings_show,
++ sched_mc_power_savings_store);
++#endif
++
++#ifdef CONFIG_SCHED_SMT
++static ssize_t sched_smt_power_savings_show(struct sysdev_class *dev,
++ struct sysdev_class_attribute *attr,
++ char *page)
++{
++ return sprintf(page, "%u\n", sched_smt_power_savings);
++}
++static ssize_t sched_smt_power_savings_store(struct sysdev_class *dev,
++ struct sysdev_class_attribute *attr,
++ const char *buf, size_t count)
++{
++ return sched_power_savings_store(buf, count, 1);
++}
++static SYSDEV_CLASS_ATTR(sched_smt_power_savings, 0644,
++ sched_smt_power_savings_show,
++ sched_smt_power_savings_store);
++#endif
++
++int __init sched_create_sysfs_power_savings_entries(struct sysdev_class *cls)
++{
++ int err = 0;
++
++#ifdef CONFIG_SCHED_SMT
++ if (smt_capable())
++ err = sysfs_create_file(&cls->kset.kobj,
++ &attr_sched_smt_power_savings.attr);
++#endif
++#ifdef CONFIG_SCHED_MC
++ if (!err && mc_capable())
++ err = sysfs_create_file(&cls->kset.kobj,
++ &attr_sched_mc_power_savings.attr);
++#endif
++ return err;
++}
++#endif /* CONFIG_SCHED_MC || CONFIG_SCHED_SMT */
++
++/*
++ * Update cpusets according to cpu_active mask. If cpusets are
++ * disabled, cpuset_update_active_cpus() becomes a simple wrapper
++ * around partition_sched_domains().
++ */
++static int cpuset_cpu_active(struct notifier_block *nfb, unsigned long action,
++ void *hcpu)
++{
++ switch (action & ~CPU_TASKS_FROZEN) {
++ case CPU_ONLINE:
++ case CPU_DOWN_FAILED:
++ cpuset_update_active_cpus();
++ return NOTIFY_OK;
++ default:
++ return NOTIFY_DONE;
++ }
++}
++
++static int cpuset_cpu_inactive(struct notifier_block *nfb, unsigned long action,
++ void *hcpu)
++{
++ switch (action & ~CPU_TASKS_FROZEN) {
++ case CPU_DOWN_PREPARE:
++ cpuset_update_active_cpus();
++ return NOTIFY_OK;
++ default:
++ return NOTIFY_DONE;
++ }
++}
++
++static int update_runtime(struct notifier_block *nfb,
++ unsigned long action, void *hcpu)
++{
++ switch (action) {
++ case CPU_DOWN_PREPARE:
++ case CPU_DOWN_PREPARE_FROZEN:
++ return NOTIFY_OK;
++
++ case CPU_DOWN_FAILED:
++ case CPU_DOWN_FAILED_FROZEN:
++ case CPU_ONLINE:
++ case CPU_ONLINE_FROZEN:
++ return NOTIFY_OK;
++
++ default:
++ return NOTIFY_DONE;
++ }
++}
++
++#if defined(CONFIG_SCHED_SMT) || defined(CONFIG_SCHED_MC)
++/*
++ * Cheaper version of the below functions in case support for SMT and MC is
++ * compiled in but CPUs have no siblings.
++ */
++static int sole_cpu_idle(unsigned long cpu)
++{
++ return rq_idle(cpu_rq(cpu));
++}
++#endif
++#ifdef CONFIG_SCHED_SMT
++/* All this CPU's SMT siblings are idle */
++static int siblings_cpu_idle(unsigned long cpu)
++{
++ return cpumask_subset(&(cpu_rq(cpu)->smt_siblings),
++ &grq.cpu_idle_map);
++}
++#endif
++#ifdef CONFIG_SCHED_MC
++/* All this CPU's shared cache siblings are idle */
++static int cache_cpu_idle(unsigned long cpu)
++{
++ return cpumask_subset(&(cpu_rq(cpu)->cache_siblings),
++ &grq.cpu_idle_map);
++}
++#endif
++
++void __init sched_init_smp(void)
++{
++ struct sched_domain *sd;
++ int cpu, cpus;
++
++ cpumask_var_t non_isolated_cpus;
++
++ alloc_cpumask_var(&non_isolated_cpus, GFP_KERNEL);
++ alloc_cpumask_var(&fallback_doms, GFP_KERNEL);
++
++#if defined(CONFIG_NUMA)
++ sched_group_nodes_bycpu = kzalloc(nr_cpu_ids * sizeof(void **),
++ GFP_KERNEL);
++ BUG_ON(sched_group_nodes_bycpu == NULL);
++#endif
++ get_online_cpus();
++ mutex_lock(&sched_domains_mutex);
++ arch_init_sched_domains(cpu_active_mask);
++ cpumask_andnot(non_isolated_cpus, cpu_possible_mask, cpu_isolated_map);
++ if (cpumask_empty(non_isolated_cpus))
++ cpumask_set_cpu(smp_processor_id(), non_isolated_cpus);
++ mutex_unlock(&sched_domains_mutex);
++ put_online_cpus();
++
++ hotcpu_notifier(cpuset_cpu_active, CPU_PRI_CPUSET_ACTIVE);
++ hotcpu_notifier(cpuset_cpu_inactive, CPU_PRI_CPUSET_INACTIVE);
++
++ /* RT runtime code needs to handle some hotplug events */
++ hotcpu_notifier(update_runtime, 0);
++
++ /* Move init over to a non-isolated CPU */
++ if (set_cpus_allowed_ptr(current, non_isolated_cpus) < 0)
++ BUG();
++ free_cpumask_var(non_isolated_cpus);
++
++ /*
++ * Assume that every added cpu gives us slightly less overall latency
++ * allowing us to increase the base rr_interval, non-linearly and with
++ * an upper bound.
++ */
++ cpus = num_online_cpus();
++ rr_interval = rr_interval * (4 * cpus + 4) / (cpus + 6);
++
++ grq_lock_irq();
++ /*
++ * Set up the relative cache distance of each online cpu from each
++ * other in a simple array for quick lookup. Locality is determined
++ * by the closest sched_domain that CPUs are separated by. CPUs with
++ * shared cache in SMT and MC are treated as local. Separate CPUs
++ * (within the same package or physically) within the same node are
++ * treated as not local. CPUs not even in the same domain (different
++ * nodes) are treated as very distant.
++ */
++ for_each_online_cpu(cpu) {
++ struct rq *rq = cpu_rq(cpu);
++ for_each_domain(cpu, sd) {
++ unsigned long locality;
++ int other_cpu;
++
++#ifdef CONFIG_SCHED_SMT
++ if (sd->level == SD_LV_SIBLING) {
++ for_each_cpu_mask(other_cpu, *sched_domain_span(sd))
++ cpumask_set_cpu(other_cpu, &rq->smt_siblings);
++ }
++#endif
++#ifdef CONFIG_SCHED_MC
++ if (sd->level == SD_LV_MC) {
++ for_each_cpu_mask(other_cpu, *sched_domain_span(sd))
++ cpumask_set_cpu(other_cpu, &rq->cache_siblings);
++ }
++#endif
++ if (sd->level <= SD_LV_SIBLING)
++ locality = 1;
++ else if (sd->level <= SD_LV_MC)
++ locality = 2;
++ else if (sd->level <= SD_LV_NODE)
++ locality = 3;
++ else
++ continue;
++
++ for_each_cpu_mask(other_cpu, *sched_domain_span(sd)) {
++ if (locality < rq->cpu_locality[other_cpu])
++ rq->cpu_locality[other_cpu] = locality;
++ }
++ }
++
++/*
++ * Each runqueue has its own function in case it doesn't have
++ * siblings of its own allowing mixed topologies.
++ */
++#ifdef CONFIG_SCHED_SMT
++ if (cpus_weight(rq->smt_siblings) > 1)
++ rq->siblings_idle = siblings_cpu_idle;
++#endif
++#ifdef CONFIG_SCHED_MC
++ if (cpus_weight(rq->cache_siblings) > 1)
++ rq->cache_idle = cache_cpu_idle;
++#endif
++ }
++ grq_unlock_irq();
++}
++#else
++void __init sched_init_smp(void)
++{
++}
++#endif /* CONFIG_SMP */
++
++unsigned int sysctl_timer_migration = 1;
++
++int in_sched_functions(unsigned long addr)
++{
++ return in_lock_functions(addr) ||
++ (addr >= (unsigned long)__sched_text_start
++ && addr < (unsigned long)__sched_text_end);
++}
++
++void __init sched_init(void)
++{
++ int i;
++ struct rq *rq;
++
++ prio_ratios[0] = 128;
++ for (i = 1 ; i < PRIO_RANGE ; i++)
++ prio_ratios[i] = prio_ratios[i - 1] * 11 / 10;
++
++ raw_spin_lock_init(&grq.lock);
++ grq.nr_running = grq.nr_uninterruptible = grq.nr_switches = 0;
++ grq.niffies = 0;
++ grq.last_jiffy = jiffies;
++ raw_spin_lock_init(&grq.iso_lock);
++ grq.iso_ticks = grq.iso_refractory = 0;
++#ifdef CONFIG_SMP
++ init_defrootdomain();
++ grq.qnr = grq.idle_cpus = 0;
++ cpumask_clear(&grq.cpu_idle_map);
++#else
++ uprq = &per_cpu(runqueues, 0);
++#endif
++ for_each_possible_cpu(i) {
++ rq = cpu_rq(i);
++ rq->user_pc = rq->nice_pc = rq->softirq_pc = rq->system_pc =
++ rq->iowait_pc = rq->idle_pc = 0;
++ rq->dither = 0;
++#ifdef CONFIG_SMP
++ rq->last_niffy = 0;
++ rq->sd = NULL;
++ rq->rd = NULL;
++ rq->online = 0;
++ rq->cpu = i;
++ rq_attach_root(rq, &def_root_domain);
++#endif
++ atomic_set(&rq->nr_iowait, 0);
++ }
++
++#ifdef CONFIG_SMP
++ nr_cpu_ids = i;
++ /*
++ * Set the base locality for cpu cache distance calculation to
++ * "distant" (3). Make sure the distance from a CPU to itself is 0.
++ */
++ for_each_possible_cpu(i) {
++ int j;
++
++ rq = cpu_rq(i);
++#ifdef CONFIG_SCHED_SMT
++ cpumask_clear(&rq->smt_siblings);
++ cpumask_set_cpu(i, &rq->smt_siblings);
++ rq->siblings_idle = sole_cpu_idle;
++ cpumask_set_cpu(i, &rq->smt_siblings);
++#endif
++#ifdef CONFIG_SCHED_MC
++ cpumask_clear(&rq->cache_siblings);
++ cpumask_set_cpu(i, &rq->cache_siblings);
++ rq->cache_idle = sole_cpu_idle;
++ cpumask_set_cpu(i, &rq->cache_siblings);
++#endif
++ rq->cpu_locality = kmalloc(nr_cpu_ids * sizeof(unsigned long),
++ GFP_NOWAIT);
++ for_each_possible_cpu(j) {
++ if (i == j)
++ rq->cpu_locality[j] = 0;
++ else
++ rq->cpu_locality[j] = 4;
++ }
++ }
++#endif
++
++ for (i = 0; i < PRIO_LIMIT; i++)
++ INIT_LIST_HEAD(grq.queue + i);
++ /* delimiter for bitsearch */
++ __set_bit(PRIO_LIMIT, grq.prio_bitmap);
++
++#ifdef CONFIG_PREEMPT_NOTIFIERS
++ INIT_HLIST_HEAD(&init_task.preempt_notifiers);
++#endif
++
++#ifdef CONFIG_RT_MUTEXES
++ plist_head_init_raw(&init_task.pi_waiters, &init_task.pi_lock);
++#endif
++
++ /*
++ * The boot idle thread does lazy MMU switching as well:
++ */
++ atomic_inc(&init_mm.mm_count);
++ enter_lazy_tlb(&init_mm, current);
++
++ /*
++ * Make us the idle thread. Technically, schedule() should not be
++ * called from this thread, however somewhere below it might be,
++ * but because we are the idle thread, we just pick up running again
++ * when this runqueue becomes "idle".
++ */
++ init_idle(current, smp_processor_id());
++
++ /* Allocate the nohz_cpu_mask if CONFIG_CPUMASK_OFFSTACK */
++ zalloc_cpumask_var(&nohz_cpu_mask, GFP_NOWAIT);
++#ifdef CONFIG_SMP
++ /* May be allocated at isolcpus cmdline parse time */
++ if (cpu_isolated_map == NULL)
++ zalloc_cpumask_var(&cpu_isolated_map, GFP_NOWAIT);
++#endif /* SMP */
++ perf_event_init();
++}
++
++#ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
++static inline int preempt_count_equals(int preempt_offset)
++{
++ int nested = (preempt_count() & ~PREEMPT_ACTIVE) + rcu_preempt_depth();
++
++ return (nested == PREEMPT_INATOMIC_BASE + preempt_offset);
++}
++
++void __might_sleep(const char *file, int line, int preempt_offset)
++{
++#ifdef in_atomic
++ static unsigned long prev_jiffy; /* ratelimiting */
++
++ if ((preempt_count_equals(preempt_offset) && !irqs_disabled()) ||
++ system_state != SYSTEM_RUNNING || oops_in_progress)
++ return;
++ if (time_before(jiffies, prev_jiffy + HZ) && prev_jiffy)
++ return;
++ prev_jiffy = jiffies;
++
++ printk(KERN_ERR
++ "BUG: sleeping function called from invalid context at %s:%d\n",
++ file, line);
++ printk(KERN_ERR
++ "in_atomic(): %d, irqs_disabled(): %d, pid: %d, name: %s\n",
++ in_atomic(), irqs_disabled(),
++ current->pid, current->comm);
++
++ debug_show_held_locks(current);
++ if (irqs_disabled())
++ print_irqtrace_events(current);
++ dump_stack();
++#endif
++}
++EXPORT_SYMBOL(__might_sleep);
++#endif
++
++#ifdef CONFIG_MAGIC_SYSRQ
++void normalize_rt_tasks(void)
++{
++ struct task_struct *g, *p;
++ unsigned long flags;
++ struct rq *rq;
++ int queued;
++
++ read_lock_irq(&tasklist_lock);
++
++ do_each_thread(g, p) {
++ if (!rt_task(p) && !iso_task(p))
++ continue;
++
++ raw_spin_lock_irqsave(&p->pi_lock, flags);
++ rq = __task_grq_lock(p);
++
++ queued = task_queued(p);
++ if (queued)
++ dequeue_task(p);
++ __setscheduler(p, rq, SCHED_NORMAL, 0);
++ if (queued) {
++ enqueue_task(p);
++ try_preempt(p, rq);
++ }
++
++ __task_grq_unlock();
++ raw_spin_unlock_irqrestore(&p->pi_lock, flags);
++ } while_each_thread(g, p);
++
++ read_unlock_irq(&tasklist_lock);
++}
++#endif /* CONFIG_MAGIC_SYSRQ */
++
++#if defined(CONFIG_IA64) || defined(CONFIG_KGDB_KDB)
++/*
++ * These functions are only useful for the IA64 MCA handling, or kdb.
++ *
++ * They can only be called when the whole system has been
++ * stopped - every CPU needs to be quiescent, and no scheduling
++ * activity can take place. Using them for anything else would
++ * be a serious bug, and as a result, they aren't even visible
++ * under any other configuration.
++ */
++
++/**
++ * curr_task - return the current task for a given cpu.
++ * @cpu: the processor in question.
++ *
++ * ONLY VALID WHEN THE WHOLE SYSTEM IS STOPPED!
++ */
++struct task_struct *curr_task(int cpu)
++{
++ return cpu_curr(cpu);
++}
++
++#endif /* defined(CONFIG_IA64) || defined(CONFIG_KGDB_KDB) */
++
++#ifdef CONFIG_IA64
++/**
++ * set_curr_task - set the current task for a given cpu.
++ * @cpu: the processor in question.
++ * @p: the task pointer to set.
++ *
++ * Description: This function must only be used when non-maskable interrupts
++ * are serviced on a separate stack. It allows the architecture to switch the
++ * notion of the current task on a cpu in a non-blocking manner. This function
++ * must be called with all CPU's synchronised, and interrupts disabled, the
++ * and caller must save the original value of the current task (see
++ * curr_task() above) and restore that value before reenabling interrupts and
++ * re-starting the system.
++ *
++ * ONLY VALID WHEN THE WHOLE SYSTEM IS STOPPED!
++ */
++void set_curr_task(int cpu, struct task_struct *p)
++{
++ cpu_curr(cpu) = p;
++}
++
++#endif
++
++/*
++ * Use precise platform statistics if available:
++ */
++#ifdef CONFIG_VIRT_CPU_ACCOUNTING
++void task_times(struct task_struct *p, cputime_t *ut, cputime_t *st)
++{
++ *ut = p->utime;
++ *st = p->stime;
++}
++
++void thread_group_times(struct task_struct *p, cputime_t *ut, cputime_t *st)
++{
++ struct task_cputime cputime;
++
++ thread_group_cputime(p, &cputime);
++
++ *ut = cputime.utime;
++ *st = cputime.stime;
++}
++#else
++
++#ifndef nsecs_to_cputime
++# define nsecs_to_cputime(__nsecs) nsecs_to_jiffies(__nsecs)
++#endif
++
++void task_times(struct task_struct *p, cputime_t *ut, cputime_t *st)
++{
++ cputime_t rtime, utime = p->utime, total = cputime_add(utime, p->stime);
++
++ rtime = nsecs_to_cputime(p->sched_time);
++
++ if (total) {
++ u64 temp;
++
++ temp = (u64)(rtime * utime);
++ do_div(temp, total);
++ utime = (cputime_t)temp;
++ } else
++ utime = rtime;
++
++ /*
++ * Compare with previous values, to keep monotonicity:
++ */
++ p->prev_utime = max(p->prev_utime, utime);
++ p->prev_stime = max(p->prev_stime, cputime_sub(rtime, p->prev_utime));
++
++ *ut = p->prev_utime;
++ *st = p->prev_stime;
++}
++
++/*
++ * Must be called with siglock held.
++ */
++void thread_group_times(struct task_struct *p, cputime_t *ut, cputime_t *st)
++{
++ struct signal_struct *sig = p->signal;
++ struct task_cputime cputime;
++ cputime_t rtime, utime, total;
++
++ thread_group_cputime(p, &cputime);
++
++ total = cputime_add(cputime.utime, cputime.stime);
++ rtime = nsecs_to_cputime(cputime.sum_exec_runtime);
++
++ if (total) {
++ u64 temp;
++
++ temp = (u64)(rtime * cputime.utime);
++ do_div(temp, total);
++ utime = (cputime_t)temp;
++ } else
++ utime = rtime;
++
++ sig->prev_utime = max(sig->prev_utime, utime);
++ sig->prev_stime = max(sig->prev_stime,
++ cputime_sub(rtime, sig->prev_utime));
++
++ *ut = sig->prev_utime;
++ *st = sig->prev_stime;
++}
++#endif
++
++inline cputime_t task_gtime(struct task_struct *p)
++{
++ return p->gtime;
++}
++
++void __cpuinit init_idle_bootup_task(struct task_struct *idle)
++{}
++
++#ifdef CONFIG_SCHED_DEBUG
++void proc_sched_show_task(struct task_struct *p, struct seq_file *m)
++{}
++
++void proc_sched_set_task(struct task_struct *p)
++{}
++#endif
++
++/* No RCU torture test support */
++void synchronize_sched_expedited(void)
++{
++ barrier();
++}
++EXPORT_SYMBOL_GPL(synchronize_sched_expedited);
++
++#ifdef CONFIG_SMP
++unsigned long default_scale_freq_power(struct sched_domain *sd, int cpu)
++{
++ return SCHED_LOAD_SCALE;
++}
++
++unsigned long default_scale_smt_power(struct sched_domain *sd, int cpu)
++{
++ unsigned long weight = cpumask_weight(sched_domain_span(sd));
++ unsigned long smt_gain = sd->smt_gain;
++
++ smt_gain /= weight;
++
++ return smt_gain;
++}
++#endif
+Index: linux-2.6.37-ck2/kernel/sched.c
+===================================================================
+--- linux-2.6.37-ck2.orig/kernel/sched.c 2011-01-06 14:04:10.000000000 +1100
++++ linux-2.6.37-ck2/kernel/sched.c 2011-02-14 09:47:50.994252001 +1100
+@@ -1,3 +1,6 @@
++#ifdef CONFIG_SCHED_BFS
++#include "sched_bfs.c"
++#else
+ /*
+ * kernel/sched.c
+ *
+@@ -9603,3 +9606,4 @@
+ EXPORT_SYMBOL_GPL(synchronize_sched_expedited);
+
+ #endif /* #else #ifndef CONFIG_SMP */
++#endif /* CONFIG_SCHED_BFS */
+Index: linux-2.6.37-ck2/kernel/sysctl.c
+===================================================================
+--- linux-2.6.37-ck2.orig/kernel/sysctl.c 2011-01-06 14:04:10.000000000 +1100
++++ linux-2.6.37-ck2/kernel/sysctl.c 2011-02-14 09:47:50.995252001 +1100
+@@ -117,7 +117,12 @@
+ static int __maybe_unused one = 1;
+ static int __maybe_unused two = 2;
+ static unsigned long one_ul = 1;
+-static int one_hundred = 100;
++static int __maybe_unused one_hundred = 100;
++#ifdef CONFIG_SCHED_BFS
++extern int rr_interval;
++extern int sched_iso_cpu;
++static int __read_mostly one_thousand = 1000;
++#endif
+ #ifdef CONFIG_PRINTK
+ static int ten_thousand = 10000;
+ #endif
+@@ -252,7 +257,7 @@
+ { }
+ };
+
+-#ifdef CONFIG_SCHED_DEBUG
++#if defined(CONFIG_SCHED_DEBUG) && !defined(CONFIG_SCHED_BFS)
+ static int min_sched_granularity_ns = 100000; /* 100 usecs */
+ static int max_sched_granularity_ns = NSEC_PER_SEC; /* 1 second */
+ static int min_wakeup_granularity_ns; /* 0 usecs */
+@@ -269,6 +274,7 @@
+ #endif
+
+ static struct ctl_table kern_table[] = {
++#ifndef CONFIG_SCHED_BFS
+ {
+ .procname = "sched_child_runs_first",
+ .data = &sysctl_sched_child_runs_first,
+@@ -382,6 +388,7 @@
+ .mode = 0644,
+ .proc_handler = proc_dointvec,
+ },
++#endif /* !CONFIG_SCHED_BFS */
+ #ifdef CONFIG_PROVE_LOCKING
+ {
+ .procname = "prove_locking",
+@@ -815,6 +822,26 @@
+ .proc_handler = proc_dointvec,
+ },
+ #endif
++#ifdef CONFIG_SCHED_BFS
++ {
++ .procname = "rr_interval",
++ .data = &rr_interval,
++ .maxlen = sizeof (int),
++ .mode = 0644,
++ .proc_handler = &proc_dointvec_minmax,
++ .extra1 = &one,
++ .extra2 = &one_thousand,
++ },
++ {
++ .procname = "iso_cpu",
++ .data = &sched_iso_cpu,
++ .maxlen = sizeof (int),
++ .mode = 0644,
++ .proc_handler = &proc_dointvec_minmax,
++ .extra1 = &zero,
++ .extra2 = &one_hundred,
++ },
++#endif
+ #if defined(CONFIG_S390) && defined(CONFIG_SMP)
+ {
+ .procname = "spin_retry",
+Index: linux-2.6.37-ck2/lib/Kconfig.debug
+===================================================================
+--- linux-2.6.37-ck2.orig/lib/Kconfig.debug 2011-01-06 14:04:10.000000000 +1100
++++ linux-2.6.37-ck2/lib/Kconfig.debug 2011-02-14 09:47:50.995252001 +1100
+@@ -833,7 +833,7 @@
+
+ config RCU_TORTURE_TEST
+ tristate "torture tests for RCU"
+- depends on DEBUG_KERNEL
++ depends on DEBUG_KERNEL && !SCHED_BFS
+ default n
+ help
+ This option provides a kernel module that runs torture tests
+Index: linux-2.6.37-ck2/include/linux/jiffies.h
+===================================================================
+--- linux-2.6.37-ck2.orig/include/linux/jiffies.h 2010-02-25 21:51:52.000000000 +1100
++++ linux-2.6.37-ck2/include/linux/jiffies.h 2011-02-14 09:47:50.995252001 +1100
+@@ -164,7 +164,7 @@
+ * Have the 32 bit jiffies value wrap 5 minutes after boot
+ * so jiffies wrap bugs show up earlier.
+ */
+-#define INITIAL_JIFFIES ((unsigned long)(unsigned int) (-300*HZ))
++#define INITIAL_JIFFIES ((unsigned long)(unsigned int) (-10*HZ))
+
+ /*
+ * Change timeval to jiffies, trying to avoid the
+Index: linux-2.6.37-ck2/mm/vmscan.c
+===================================================================
+--- linux-2.6.37-ck2.orig/mm/vmscan.c 2011-01-06 14:04:10.000000000 +1100
++++ linux-2.6.37-ck2/mm/vmscan.c 2011-02-14 10:11:01.693252000 +1100
+@@ -36,6 +36,7 @@
+ #include <linux/rwsem.h>
+ #include <linux/delay.h>
+ #include <linux/kthread.h>
++#include <linux/timer.h>
+ #include <linux/freezer.h>
+ #include <linux/memcontrol.h>
+ #include <linux/delayacct.h>
+@@ -133,7 +134,7 @@
+ /*
+ * From 0 .. 100. Higher means more swappy.
+ */
+-int vm_swappiness = 60;
++int vm_swappiness;
+ long vm_total_pages; /* The total number of pages which the VM controls */
+
+ static LIST_HEAD(shrinker_list);
+@@ -900,7 +901,7 @@
+
+ activate_locked:
+ /* Not a candidate for swapping, so reclaim swap space. */
+- if (PageSwapCache(page) && vm_swap_full())
++ if (PageSwapCache(page))
+ try_to_free_swap(page);
+ VM_BUG_ON(PageActive(page));
+ SetPageActive(page);
+@@ -1855,6 +1856,35 @@
+ }
+
+ /*
++ * Helper functions to adjust nice level of kswapd, based on the priority of
++ * the task (p) that called it. If it is already higher priority we do not
++ * demote its nice level since it is still working on behalf of a higher
++ * priority task. With kernel threads we leave it at nice 0.
++ *
++ * We don't ever run kswapd real time, so if a real time task calls kswapd we
++ * set it to highest SCHED_NORMAL priority.
++ */
++static inline int effective_sc_prio(struct task_struct *p)
++{
++ if (likely(p->mm)) {
++ if (rt_task(p))
++ return -20;
++ if (p->policy == SCHED_IDLEPRIO)
++ return 19;
++ return task_nice(p);
++ }
++ return 0;
++}
++
++static void set_kswapd_nice(struct task_struct *kswapd, int active)
++{
++ long nice = effective_sc_prio(current);
++
++ if (task_nice(kswapd) > nice || !active)
++ set_user_nice(kswapd, nice);
++}
++
++/*
+ * This is the direct reclaim path, for page-allocating processes. We only
+ * try to reclaim pages from zones which will satisfy the caller's allocation
+ * request.
+@@ -2371,6 +2401,8 @@
+ return sc.nr_reclaimed;
+ }
+
++#define WT_EXPIRY (HZ * 5) /* Time to wakeup watermark_timer */
++
+ /*
+ * The background pageout daemon, started as a kernel thread
+ * from the init process.
+@@ -2421,6 +2453,8 @@
+ unsigned long new_order;
+ int ret;
+
++ /* kswapd has been busy so delay watermark_timer */
++ mod_timer(&pgdat->watermark_timer, jiffies + WT_EXPIRY);
+ prepare_to_wait(&pgdat->kswapd_wait, &wait, TASK_INTERRUPTIBLE);
+ new_order = pgdat->kswapd_max_order;
+ pgdat->kswapd_max_order = 0;
+@@ -2457,6 +2491,7 @@
+ }
+ }
+
++ set_user_nice(tsk, 0);
+ order = pgdat->kswapd_max_order;
+ }
+ finish_wait(&pgdat->kswapd_wait, &wait);
+@@ -2483,6 +2518,7 @@
+ void wakeup_kswapd(struct zone *zone, int order)
+ {
+ pg_data_t *pgdat;
++ int active;
+
+ if (!populated_zone(zone))
+ return;
+@@ -2495,7 +2531,9 @@
+ pgdat = zone->zone_pgdat;
+ if (pgdat->kswapd_max_order < order)
+ pgdat->kswapd_max_order = order;
+- if (!waitqueue_active(&pgdat->kswapd_wait))
++ active = waitqueue_active(&pgdat->kswapd_wait);
++ set_kswapd_nice(pgdat->kswapd, active);
++ if (!active)
+ return;
+ if (zone_watermark_ok_safe(zone, order, low_wmark_pages(zone), 0, 0))
+ return;
+@@ -2601,20 +2639,57 @@
+ }
+
+ /*
++ * We wake up kswapd every WT_EXPIRY till free ram is above pages_lots
++ */
++static void watermark_wakeup(unsigned long data)
++{
++ pg_data_t *pgdat = (pg_data_t *)data;
++ struct timer_list *wt = &pgdat->watermark_timer;
++ int i;
++
++ if (!waitqueue_active(&pgdat->kswapd_wait) || above_background_load())
++ goto out;
++ for (i = pgdat->nr_zones - 1; i >= 0; i--) {
++ struct zone *z = pgdat->node_zones + i;
++
++ if (!populated_zone(z) || is_highmem(z)) {
++ /* We are better off leaving highmem full */
++ continue;
++ }
++ if (!zone_watermark_ok(z, 0, lots_wmark_pages(z), 0, 0)) {
++ wake_up_interruptible(&pgdat->kswapd_wait);
++ goto out;
++ }
++ }
++out:
++ mod_timer(wt, jiffies + WT_EXPIRY);
++ return;
++}
++
++/*
+ * This kswapd start function will be called by init and node-hot-add.
+ * On node-hot-add, kswapd will moved to proper cpus if cpus are hot-added.
+ */
+ int kswapd_run(int nid)
+ {
+ pg_data_t *pgdat = NODE_DATA(nid);
++ struct timer_list *wt;
+ int ret = 0;
+
+ if (pgdat->kswapd)
+ return 0;
+
++ wt = &pgdat->watermark_timer;
++ init_timer(wt);
++ wt->data = (unsigned long)pgdat;
++ wt->function = watermark_wakeup;
++ wt->expires = jiffies + WT_EXPIRY;
++ add_timer(wt);
++
+ pgdat->kswapd = kthread_run(kswapd, pgdat, "kswapd%d", nid);
+ if (IS_ERR(pgdat->kswapd)) {
+ /* failure at boot is fatal */
++ del_timer(wt);
+ BUG_ON(system_state == SYSTEM_BOOTING);
+ printk("Failed to start kswapd on node %d\n",nid);
+ ret = -1;
+Index: linux-2.6.37-ck2/include/linux/swap.h
+===================================================================
+--- linux-2.6.37-ck2.orig/include/linux/swap.h 2011-01-06 14:04:10.000000000 +1100
++++ linux-2.6.37-ck2/include/linux/swap.h 2011-02-14 10:11:09.770252000 +1100
+@@ -192,7 +192,7 @@
+ int next; /* swapfile to be used next */
+ };
+
+-/* Swap 50% full? Release swapcache more aggressively.. */
++/* Swap 50% full? */
+ #define vm_swap_full() (nr_swap_pages*2 < total_swap_pages)
+
+ /* linux/mm/page_alloc.c */
+@@ -206,6 +206,7 @@
+
+
+ /* linux/mm/swap.c */
++extern void ____lru_cache_add(struct page *, enum lru_list lru, int tail);
+ extern void __lru_cache_add(struct page *, enum lru_list lru);
+ extern void lru_cache_add_lru(struct page *, enum lru_list lru);
+ extern void activate_page(struct page *);
+@@ -226,9 +227,14 @@
+ __lru_cache_add(page, LRU_INACTIVE_ANON);
+ }
+
++static inline void lru_cache_add_file_tail(struct page *page, int tail)
++{
++ ____lru_cache_add(page, LRU_INACTIVE_FILE, tail);
++}
++
+ static inline void lru_cache_add_file(struct page *page)
+ {
+- __lru_cache_add(page, LRU_INACTIVE_FILE);
++ ____lru_cache_add(page, LRU_INACTIVE_FILE, 0);
+ }
+
+ /* LRU Isolation modes. */
+@@ -348,9 +354,10 @@
+ extern void grab_swap_token(struct mm_struct *);
+ extern void __put_swap_token(struct mm_struct *);
+
++/* Only allow swap token to have effect if swap is full */
+ static inline int has_swap_token(struct mm_struct *mm)
+ {
+- return (mm == swap_token_mm);
++ return (mm == swap_token_mm && vm_swap_full());
+ }
+
+ static inline void put_swap_token(struct mm_struct *mm)
+Index: linux-2.6.37-ck2/mm/memory.c
+===================================================================
+--- linux-2.6.37-ck2.orig/mm/memory.c 2011-01-06 14:04:10.000000000 +1100
++++ linux-2.6.37-ck2/mm/memory.c 2011-02-14 10:11:00.984252001 +1100
+@@ -2754,7 +2754,7 @@
+ mem_cgroup_commit_charge_swapin(page, ptr);
+
+ swap_free(entry);
+- if (vm_swap_full() || (vma->vm_flags & VM_LOCKED) || PageMlocked(page))
++ if ((vma->vm_flags & VM_LOCKED) || PageMlocked(page))
+ try_to_free_swap(page);
+ unlock_page(page);
+ if (swapcache) {
+Index: linux-2.6.37-ck2/mm/swapfile.c
+===================================================================
+--- linux-2.6.37-ck2.orig/mm/swapfile.c 2011-01-06 14:04:10.000000000 +1100
++++ linux-2.6.37-ck2/mm/swapfile.c 2011-02-14 10:11:00.985252001 +1100
+@@ -321,7 +321,7 @@
+ scan_base = offset = si->lowest_bit;
+
+ /* reuse swap entry of cache-only swap if not busy. */
+- if (vm_swap_full() && si->swap_map[offset] == SWAP_HAS_CACHE) {
++ if (si->swap_map[offset] == SWAP_HAS_CACHE) {
+ int swap_was_freed;
+ spin_unlock(&swap_lock);
+ swap_was_freed = __try_to_reclaim_swap(si, offset);
+@@ -410,7 +410,7 @@
+ spin_lock(&swap_lock);
+ goto checks;
+ }
+- if (vm_swap_full() && si->swap_map[offset] == SWAP_HAS_CACHE) {
++ if (si->swap_map[offset] == SWAP_HAS_CACHE) {
+ spin_lock(&swap_lock);
+ goto checks;
+ }
+@@ -425,7 +425,7 @@
+ spin_lock(&swap_lock);
+ goto checks;
+ }
+- if (vm_swap_full() && si->swap_map[offset] == SWAP_HAS_CACHE) {
++ if (si->swap_map[offset] == SWAP_HAS_CACHE) {
+ spin_lock(&swap_lock);
+ goto checks;
+ }
+@@ -739,8 +739,7 @@
+ * Not mapped elsewhere, or swap space full? Free it!
+ * Also recheck PageSwapCache now page is locked (above).
+ */
+- if (PageSwapCache(page) && !PageWriteback(page) &&
+- (!page_mapped(page) || vm_swap_full())) {
++ if (PageSwapCache(page) && !PageWriteback(page)) {
+ delete_from_swap_cache(page);
+ SetPageDirty(page);
+ }
+Index: linux-2.6.37-ck2/include/linux/mmzone.h
+===================================================================
+--- linux-2.6.37-ck2.orig/include/linux/mmzone.h 2011-01-06 14:04:10.000000000 +1100
++++ linux-2.6.37-ck2/include/linux/mmzone.h 2011-02-14 10:11:01.470252001 +1100
+@@ -15,6 +15,7 @@
+ #include <linux/seqlock.h>
+ #include <linux/nodemask.h>
+ #include <linux/pageblock-flags.h>
++#include <linux/timer.h>
+ #include <generated/bounds.h>
+ #include <asm/atomic.h>
+ #include <asm/page.h>
+@@ -161,12 +162,14 @@
+ WMARK_MIN,
+ WMARK_LOW,
+ WMARK_HIGH,
++ WMARK_LOTS,
+ NR_WMARK
+ };
+
+ #define min_wmark_pages(z) (z->watermark[WMARK_MIN])
+ #define low_wmark_pages(z) (z->watermark[WMARK_LOW])
+ #define high_wmark_pages(z) (z->watermark[WMARK_HIGH])
++#define lots_wmark_pages(z) (z->watermark[WMARK_LOTS])
+
+ struct per_cpu_pages {
+ int count; /* number of pages in the list */
+@@ -343,7 +346,7 @@
+ ZONE_PADDING(_pad1_)
+
+ /* Fields commonly accessed by the page reclaim scanner */
+- spinlock_t lru_lock;
++ spinlock_t lru_lock;
+ struct zone_lru {
+ struct list_head list;
+ } lru[NR_LRU_LISTS];
+@@ -645,6 +648,7 @@
+ wait_queue_head_t kswapd_wait;
+ struct task_struct *kswapd;
+ int kswapd_max_order;
++ struct timer_list watermark_timer;
+ } pg_data_t;
+
+ #define node_present_pages(nid) (NODE_DATA(nid)->node_present_pages)
+Index: linux-2.6.37-ck2/include/linux/mm_inline.h
+===================================================================
+--- linux-2.6.37-ck2.orig/include/linux/mm_inline.h 2009-12-03 21:40:09.000000000 +1100
++++ linux-2.6.37-ck2/include/linux/mm_inline.h 2011-02-14 10:11:09.770252000 +1100
+@@ -20,14 +20,24 @@
+ }
+
+ static inline void
+-add_page_to_lru_list(struct zone *zone, struct page *page, enum lru_list l)
++__add_page_to_lru_list(struct zone *zone, struct page *page, enum lru_list l, int tail)
+ {
+- list_add(&page->lru, &zone->lru[l].list);
++ /* See if this should be added to the tail of this lru list */
++ if (tail)
++ list_add_tail(&page->lru, &zone->lru[l].list);
++ else
++ list_add(&page->lru, &zone->lru[l].list);
+ __inc_zone_state(zone, NR_LRU_BASE + l);
+ mem_cgroup_add_lru_list(page, l);
+ }
+
+ static inline void
++add_page_to_lru_list(struct zone *zone, struct page *page, enum lru_list l)
++{
++ __add_page_to_lru_list(zone, page, l, 0);
++}
++
++static inline void
+ del_page_from_lru_list(struct zone *zone, struct page *page, enum lru_list l)
+ {
+ list_del(&page->lru);
+Index: linux-2.6.37-ck2/mm/filemap.c
+===================================================================
+--- linux-2.6.37-ck2.orig/mm/filemap.c 2011-01-06 14:04:10.000000000 +1100
++++ linux-2.6.37-ck2/mm/filemap.c 2011-02-14 10:11:09.772252000 +1100
+@@ -439,8 +439,8 @@
+ }
+ EXPORT_SYMBOL(add_to_page_cache_locked);
+
+-int add_to_page_cache_lru(struct page *page, struct address_space *mapping,
+- pgoff_t offset, gfp_t gfp_mask)
++int __add_to_page_cache_lru(struct page *page, struct address_space *mapping,
++ pgoff_t offset, gfp_t gfp_mask, int tail)
+ {
+ int ret;
+
+@@ -456,12 +456,18 @@
+ ret = add_to_page_cache(page, mapping, offset, gfp_mask);
+ if (ret == 0) {
+ if (page_is_file_cache(page))
+- lru_cache_add_file(page);
++ lru_cache_add_file_tail(page, tail);
+ else
+ lru_cache_add_anon(page);
+ }
+ return ret;
+ }
++
++int add_to_page_cache_lru(struct page *page, struct address_space *mapping,
++ pgoff_t offset, gfp_t gfp_mask)
++{
++ return __add_to_page_cache_lru(page, mapping, offset, gfp_mask, 0);
++}
+ EXPORT_SYMBOL_GPL(add_to_page_cache_lru);
+
+ #ifdef CONFIG_NUMA
+@@ -968,6 +974,28 @@
+ ra->ra_pages /= 4;
+ }
+
++static inline int nr_mapped(void)
++{
++ return global_page_state(NR_FILE_MAPPED) +
++ global_page_state(NR_ANON_PAGES);
++}
++
++/*
++ * This examines how large in pages a file size is and returns 1 if it is
++ * more than half the unmapped ram. Avoid doing read_page_state which is
++ * expensive unless we already know it is likely to be large enough.
++ */
++static int large_isize(unsigned long nr_pages)
++{
++ if (nr_pages * 6 > vm_total_pages) {
++ unsigned long unmapped_ram = vm_total_pages - nr_mapped();
++
++ if (nr_pages * 2 > unmapped_ram)
++ return 1;
++ }
++ return 0;
++}
++
+ /**
+ * do_generic_file_read - generic file read routine
+ * @filp: the file to read
+@@ -992,7 +1020,7 @@
+ pgoff_t prev_index;
+ unsigned long offset; /* offset into pagecache page */
+ unsigned int prev_offset;
+- int error;
++ int error, tail = 0;
+
+ index = *ppos >> PAGE_CACHE_SHIFT;
+ prev_index = ra->prev_pos >> PAGE_CACHE_SHIFT;
+@@ -1003,7 +1031,7 @@
+ for (;;) {
+ struct page *page;
+ pgoff_t end_index;
+- loff_t isize;
++ loff_t isize = 0;
+ unsigned long nr, ret;
+
+ cond_resched();
+@@ -1177,8 +1205,16 @@
+ desc->error = -ENOMEM;
+ goto out;
+ }
+- error = add_to_page_cache_lru(page, mapping,
+- index, GFP_KERNEL);
++ /*
++ * If we know the file is large we add the pages read to the
++ * end of the lru as we're unlikely to be able to cache the
++ * whole file in ram so make those pages the first to be
++ * dropped if not referenced soon.
++ */
++ if (large_isize(end_index))
++ tail = 1;
++ error = __add_to_page_cache_lru(page, mapping,
++ index, GFP_KERNEL, tail);
+ if (error) {
+ page_cache_release(page);
+ if (error == -EEXIST)
+Index: linux-2.6.37-ck2/mm/swap.c
+===================================================================
+--- linux-2.6.37-ck2.orig/mm/swap.c 2011-01-06 14:04:10.000000000 +1100
++++ linux-2.6.37-ck2/mm/swap.c 2011-02-14 10:11:09.772252000 +1100
+@@ -215,15 +215,23 @@
+
+ EXPORT_SYMBOL(mark_page_accessed);
+
+-void __lru_cache_add(struct page *page, enum lru_list lru)
++void ______pagevec_lru_add(struct pagevec *pvec, enum lru_list lru, int tail);
++
++void ____lru_cache_add(struct page *page, enum lru_list lru, int tail)
+ {
+ struct pagevec *pvec = &get_cpu_var(lru_add_pvecs)[lru];
+
+ page_cache_get(page);
+ if (!pagevec_add(pvec, page))
+- ____pagevec_lru_add(pvec, lru);
++ ______pagevec_lru_add(pvec, lru, tail);
+ put_cpu_var(lru_add_pvecs);
+ }
++EXPORT_SYMBOL(____lru_cache_add);
++
++void __lru_cache_add(struct page *page, enum lru_list lru)
++{
++ ____lru_cache_add(page, lru, 0);
++}
+ EXPORT_SYMBOL(__lru_cache_add);
+
+ /**
+@@ -231,7 +239,7 @@
+ * @page: the page to be added to the LRU.
+ * @lru: the LRU list to which the page is added.
+ */
+-void lru_cache_add_lru(struct page *page, enum lru_list lru)
++void __lru_cache_add_lru(struct page *page, enum lru_list lru, int tail)
+ {
+ if (PageActive(page)) {
+ VM_BUG_ON(PageUnevictable(page));
+@@ -242,7 +250,12 @@
+ }
+
+ VM_BUG_ON(PageLRU(page) || PageActive(page) || PageUnevictable(page));
+- __lru_cache_add(page, lru);
++ ____lru_cache_add(page, lru, tail);
++}
++
++void lru_cache_add_lru(struct page *page, enum lru_list lru)
++{
++ __lru_cache_add_lru(page, lru, 0);
+ }
+
+ /**
+@@ -403,7 +416,7 @@
+ * Add the passed pages to the LRU, then drop the caller's refcount
+ * on them. Reinitialises the caller's pagevec.
+ */
+-void ____pagevec_lru_add(struct pagevec *pvec, enum lru_list lru)
++void ______pagevec_lru_add(struct pagevec *pvec, enum lru_list lru, int tail)
+ {
+ int i;
+ struct zone *zone = NULL;
+@@ -431,7 +444,7 @@
+ if (active)
+ SetPageActive(page);
+ update_page_reclaim_stat(zone, page, file, active);
+- add_page_to_lru_list(zone, page, lru);
++ __add_page_to_lru_list(zone, page, lru, tail);
+ }
+ if (zone)
+ spin_unlock_irq(&zone->lru_lock);
+@@ -439,6 +452,11 @@
+ pagevec_reinit(pvec);
+ }
+
++void ____pagevec_lru_add(struct pagevec *pvec, enum lru_list lru)
++{
++ ______pagevec_lru_add(pvec, lru, 0);
++}
++
+ EXPORT_SYMBOL(____pagevec_lru_add);
+
+ /*
+Index: linux-2.6.37-ck2/mm/page-writeback.c
+===================================================================
+--- linux-2.6.37-ck2.orig/mm/page-writeback.c 2011-01-06 14:04:10.000000000 +1100
++++ linux-2.6.37-ck2/mm/page-writeback.c 2011-02-14 10:11:10.037252000 +1100
+@@ -78,7 +78,7 @@
+ /*
+ * The generator of dirty data starts writeback at this percentage
+ */
+-int vm_dirty_ratio = 20;
++int vm_dirty_ratio = 5;
+
+ /*
+ * vm_dirty_bytes starts at 0 (disabled) so that it is a function of
+Index: linux-2.6.37-ck2/arch/x86/Kconfig
+===================================================================
+--- linux-2.6.37-ck2.orig/arch/x86/Kconfig 2011-01-06 14:04:08.000000000 +1100
++++ linux-2.6.37-ck2/arch/x86/Kconfig 2011-02-14 10:11:10.260252001 +1100
+@@ -1046,7 +1046,7 @@
+
+ choice
+ depends on EXPERIMENTAL
+- prompt "Memory split" if EMBEDDED
++ prompt "Memory split"
+ default VMSPLIT_3G
+ depends on X86_32
+ ---help---
+@@ -1066,17 +1066,17 @@
+ option alone!
+
+ config VMSPLIT_3G
+- bool "3G/1G user/kernel split"
++ bool "Default 896MB lowmem (3G/1G user/kernel split)"
+ config VMSPLIT_3G_OPT
+ depends on !X86_PAE
+- bool "3G/1G user/kernel split (for full 1G low memory)"
++ bool "1GB lowmem (3G/1G user/kernel split)"
+ config VMSPLIT_2G
+- bool "2G/2G user/kernel split"
++ bool "2GB lowmem (2G/2G user/kernel split)"
+ config VMSPLIT_2G_OPT
+ depends on !X86_PAE
+- bool "2G/2G user/kernel split (for full 2G low memory)"
++ bool "2GB lowmem (2G/2G user/kernel split)"
+ config VMSPLIT_1G
+- bool "1G/3G user/kernel split"
++ bool "3GB lowmem (1G/3G user/kernel split)"
+ endchoice
+
+ config PAGE_OFFSET
+Index: linux-2.6.37-ck2/kernel/Kconfig.hz
+===================================================================
+--- linux-2.6.37-ck2.orig/kernel/Kconfig.hz 2009-06-10 13:05:27.000000000 +1000
++++ linux-2.6.37-ck2/kernel/Kconfig.hz 2011-02-14 10:11:10.921252001 +1100
+@@ -4,7 +4,7 @@
+
+ choice
+ prompt "Timer frequency"
+- default HZ_250
++ default HZ_1000
+ help
+ Allows the configuration of the timer frequency. It is customary
+ to have the timer interrupt run at 1000 Hz but 100 Hz may be more
+@@ -23,13 +23,14 @@
+ with lots of processors that may show reduced performance if
+ too many timer interrupts are occurring.
+
+- config HZ_250
++ config HZ_250_NODEFAULT
+ bool "250 HZ"
+ help
+- 250 Hz is a good compromise choice allowing server performance
+- while also showing good interactive responsiveness even
+- on SMP and NUMA systems. If you are going to be using NTSC video
+- or multimedia, selected 300Hz instead.
++ 250 HZ is a lousy compromise choice allowing server interactivity
++ while also showing desktop throughput and no extra power saving on
++ laptops. No good for anything.
++
++ Recommend 100 or 1000 instead.
+
+ config HZ_300
+ bool "300 HZ"
+@@ -43,16 +44,82 @@
+ bool "1000 HZ"
+ help
+ 1000 Hz is the preferred choice for desktop systems and other
+- systems requiring fast interactive responses to events.
++ systems requiring fast interactive responses to events. Laptops
++ can also benefit from this choice without sacrificing battery life
++ if dynticks is also enabled.
++
++ config HZ_1500
++ bool "1500 HZ"
++ help
++ 1500 Hz is an insane value to use to run broken software that is Hz
++ limited.
++
++ Being over 1000, driver breakage is likely.
++
++ config HZ_2000
++ bool "2000 HZ"
++ help
++ 2000 Hz is an insane value to use to run broken software that is Hz
++ limited.
++
++ Being over 1000, driver breakage is likely.
++
++ config HZ_3000
++ bool "3000 HZ"
++ help
++ 3000 Hz is an insane value to use to run broken software that is Hz
++ limited.
++
++ Being over 1000, driver breakage is likely.
++
++ config HZ_4000
++ bool "4000 HZ"
++ help
++ 4000 Hz is an insane value to use to run broken software that is Hz
++ limited.
++
++ Being over 1000, driver breakage is likely.
++
++ config HZ_5000
++ bool "5000 HZ"
++ help
++ 5000 Hz is an obscene value to use to run broken software that is Hz
++ limited.
++
++ Being over 1000, driver breakage is likely.
++
++ config HZ_7500
++ bool "7500 HZ"
++ help
++ 7500 Hz is an obscene value to use to run broken software that is Hz
++ limited.
++
++ Being over 1000, driver breakage is likely.
++
++ config HZ_10000
++ bool "10000 HZ"
++ help
++ 10000 Hz is an obscene value to use to run broken software that is Hz
++ limited.
++
++ Being over 1000, driver breakage is likely.
++
+
+ endchoice
+
+ config HZ
+ int
+ default 100 if HZ_100
+- default 250 if HZ_250
++ default 250 if HZ_250_NODEFAULT
+ default 300 if HZ_300
+ default 1000 if HZ_1000
++ default 1500 if HZ_1500
++ default 2000 if HZ_2000
++ default 3000 if HZ_3000
++ default 4000 if HZ_4000
++ default 5000 if HZ_5000
++ default 7500 if HZ_7500
++ default 10000 if HZ_10000
+
+ config SCHED_HRTICK
+ def_bool HIGH_RES_TIMERS && (!SMP || USE_GENERIC_SMP_HELPERS)
+Index: linux-2.6.37-ck2/arch/x86/kernel/cpu/proc.c
+===================================================================
+--- linux-2.6.37-ck2.orig/arch/x86/kernel/cpu/proc.c 2009-12-03 21:39:58.000000000 +1100
++++ linux-2.6.37-ck2/arch/x86/kernel/cpu/proc.c 2011-02-14 10:11:10.919252001 +1100
+@@ -109,7 +109,7 @@
+
+ seq_printf(m, "\nbogomips\t: %lu.%02lu\n",
+ c->loops_per_jiffy/(500000/HZ),
+- (c->loops_per_jiffy/(5000/HZ)) % 100);
++ (c->loops_per_jiffy * 10 /(50000/HZ)) % 100);
+
+ #ifdef CONFIG_X86_64
+ if (c->x86_tlbsize > 0)
+Index: linux-2.6.37-ck2/arch/x86/kernel/smpboot.c
+===================================================================
+--- linux-2.6.37-ck2.orig/arch/x86/kernel/smpboot.c 2011-01-06 14:04:08.000000000 +1100
++++ linux-2.6.37-ck2/arch/x86/kernel/smpboot.c 2011-02-14 10:11:10.920252001 +1100
+@@ -497,7 +497,7 @@
+ "Total of %d processors activated (%lu.%02lu BogoMIPS).\n",
+ num_online_cpus(),
+ bogosum/(500000/HZ),
+- (bogosum/(5000/HZ))%100);
++ (bogosum * 10/(50000/HZ))%100);
+
+ pr_debug("Before bogocount - setting activated=1.\n");
+ }
+Index: linux-2.6.37-ck2/include/linux/nfsd/stats.h
+===================================================================
+--- linux-2.6.37-ck2.orig/include/linux/nfsd/stats.h 2009-06-10 13:05:27.000000000 +1000
++++ linux-2.6.37-ck2/include/linux/nfsd/stats.h 2011-02-14 10:11:10.920252001 +1100
+@@ -11,8 +11,8 @@
+
+ #include <linux/nfs4.h>
+
+-/* thread usage wraps very million seconds (approx one fortnight) */
+-#define NFSD_USAGE_WRAP (HZ*1000000)
++/* thread usage wraps every one hundred thousand seconds (approx one day) */
++#define NFSD_USAGE_WRAP (HZ*100000)
+
+ #ifdef __KERNEL__
+
+Index: linux-2.6.37-ck2/include/net/inet_timewait_sock.h
+===================================================================
+--- linux-2.6.37-ck2.orig/include/net/inet_timewait_sock.h 2010-08-02 11:12:25.000000000 +1000
++++ linux-2.6.37-ck2/include/net/inet_timewait_sock.h 2011-02-14 10:11:10.920252001 +1100
+@@ -39,8 +39,8 @@
+ * If time > 4sec, it is "slow" path, no recycling is required,
+ * so that we select tick to get range about 4 seconds.
+ */
+-#if HZ <= 16 || HZ > 4096
+-# error Unsupported: HZ <= 16 or HZ > 4096
++#if HZ <= 16 || HZ > 16384
++# error Unsupported: HZ <= 16 or HZ > 16384
+ #elif HZ <= 32
+ # define INET_TWDR_RECYCLE_TICK (5 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
+ #elif HZ <= 64
+@@ -55,8 +55,12 @@
+ # define INET_TWDR_RECYCLE_TICK (10 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
+ #elif HZ <= 2048
+ # define INET_TWDR_RECYCLE_TICK (11 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
+-#else
++#elif HZ <= 4096
+ # define INET_TWDR_RECYCLE_TICK (12 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
++#elif HZ <= 8192
++# define INET_TWDR_RECYCLE_TICK (13 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
++#else
++# define INET_TWDR_RECYCLE_TICK (14 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
+ #endif
+
+ /* TIME_WAIT reaping mechanism. */
+Index: linux-2.6.37-ck2/init/calibrate.c
+===================================================================
+--- linux-2.6.37-ck2.orig/init/calibrate.c 2010-02-25 21:51:52.000000000 +1100
++++ linux-2.6.37-ck2/init/calibrate.c 2011-02-14 10:11:10.921252001 +1100
+@@ -176,7 +176,7 @@
+ if (!printed)
+ pr_cont("%lu.%02lu BogoMIPS (lpj=%lu)\n",
+ loops_per_jiffy/(500000/HZ),
+- (loops_per_jiffy/(5000/HZ)) % 100, loops_per_jiffy);
++ (loops_per_jiffy * 10 /(50000/HZ)) % 100, loops_per_jiffy);
+
+ printed = true;
+ }
+Index: linux-2.6.37-ck2/kernel/Kconfig.preempt
+===================================================================
+--- linux-2.6.37-ck2.orig/kernel/Kconfig.preempt 2009-06-10 13:05:27.000000000 +1000
++++ linux-2.6.37-ck2/kernel/Kconfig.preempt 2011-02-14 10:11:11.217252001 +1100
+@@ -1,7 +1,7 @@
+
+ choice
+ prompt "Preemption Model"
+- default PREEMPT_NONE
++ default PREEMPT
+
+ config PREEMPT_NONE
+ bool "No Forced Preemption (Server)"
+@@ -17,7 +17,7 @@
+ latencies.
+
+ config PREEMPT_VOLUNTARY
+- bool "Voluntary Kernel Preemption (Desktop)"
++ bool "Voluntary Kernel Preemption (Nothing)"
+ help
+ This option reduces the latency of the kernel by adding more
+ "explicit preemption points" to the kernel code. These new
+@@ -31,7 +31,8 @@
+ applications to run more 'smoothly' even when the system is
+ under load.
+
+- Select this if you are building a kernel for a desktop system.
++ Select this for no system in particular (choose Preemptible
++ instead on a desktop if you know what's good for you).
+
+ config PREEMPT
+ bool "Preemptible Kernel (Low-Latency Desktop)"
+Index: linux-2.6.37-ck2/drivers/cpufreq/cpufreq_ondemand.c
+===================================================================
+--- linux-2.6.37-ck2.orig/drivers/cpufreq/cpufreq_ondemand.c 2011-01-06 14:04:08.000000000 +1100
++++ linux-2.6.37-ck2/drivers/cpufreq/cpufreq_ondemand.c 2011-02-14 10:11:11.438252001 +1100
+@@ -28,12 +28,12 @@
+ * It helps to keep variable names smaller, simpler
+ */
+
+-#define DEF_FREQUENCY_DOWN_DIFFERENTIAL (10)
+-#define DEF_FREQUENCY_UP_THRESHOLD (80)
++#define DEF_FREQUENCY_DOWN_DIFFERENTIAL (17)
++#define DEF_FREQUENCY_UP_THRESHOLD (63)
+ #define DEF_SAMPLING_DOWN_FACTOR (1)
+ #define MAX_SAMPLING_DOWN_FACTOR (100000)
+ #define MICRO_FREQUENCY_DOWN_DIFFERENTIAL (3)
+-#define MICRO_FREQUENCY_UP_THRESHOLD (95)
++#define MICRO_FREQUENCY_UP_THRESHOLD (80)
+ #define MICRO_FREQUENCY_MIN_SAMPLE_RATE (10000)
+ #define MIN_FREQUENCY_UP_THRESHOLD (11)
+ #define MAX_FREQUENCY_UP_THRESHOLD (100)
+@@ -513,10 +513,10 @@
+
+ /*
+ * Every sampling_rate, we check, if current idle time is less
+- * than 20% (default), then we try to increase frequency
++ * than 37% (default), then we try to increase frequency
+ * Every sampling_rate, we look for a the lowest
+ * frequency which can sustain the load while keeping idle time over
+- * 30%. If such a frequency exist, we try to decrease to this frequency.
++ * 50%. If such a frequency exist, we try to decrease to this frequency.
+ *
+ * Any frequency increase takes it to the maximum frequency.
+ * Frequency reduction happens at minimum steps of
+Index: linux-2.6.37-ck2/Makefile
+===================================================================
+--- linux-2.6.37-ck2.orig/Makefile 2011-01-06 14:04:07.000000000 +1100
++++ linux-2.6.37-ck2/Makefile 2011-02-14 10:11:20.469252000 +1100
+@@ -10,6 +10,10 @@
+ # Comments in this file are targeted only to the developer, do not
+ # expect to learn how to build the kernel reading this file.
+
++CKVERSION = -ck2
++CKNAME = BFS Powered
++EXTRAVERSION := $(EXTRAVERSION)$(CKVERSION)
++
+ # Do not:
+ # o use make's built-in rules and variables
+ # (this increases performance and avoids hard-to-debug behaviour);