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authornbd <nbd@3c298f89-4303-0410-b956-a3cf2f4a3e73>2009-09-24 19:23:55 +0000
committernbd <nbd@3c298f89-4303-0410-b956-a3cf2f4a3e73>2009-09-24 19:23:55 +0000
commit19b9e51722f249a7e208c127de810afdfe07833f (patch)
treecd076103d64f4a18c6db2f50c505c36b59ce3e65 /target/linux/generic-2.6/patches-2.6.31/270-sched_bfs.patch
parentc09228f0837ac811e86ebac3dcc19c3c792014e3 (diff)
add bfs to linux 2.6.31
git-svn-id: svn://svn.openwrt.org/openwrt/trunk@17699 3c298f89-4303-0410-b956-a3cf2f4a3e73
Diffstat (limited to 'target/linux/generic-2.6/patches-2.6.31/270-sched_bfs.patch')
-rw-r--r--target/linux/generic-2.6/patches-2.6.31/270-sched_bfs.patch6448
1 files changed, 6448 insertions, 0 deletions
diff --git a/target/linux/generic-2.6/patches-2.6.31/270-sched_bfs.patch b/target/linux/generic-2.6/patches-2.6.31/270-sched_bfs.patch
new file mode 100644
index 0000000000..1f805dfe5f
--- /dev/null
+++ b/target/linux/generic-2.6/patches-2.6.31/270-sched_bfs.patch
@@ -0,0 +1,6448 @@
+This patch adds support for bfs v230, modified for diff size reduction
+
+--- a/Documentation/sysctl/kernel.txt
++++ b/Documentation/sysctl/kernel.txt
+@@ -27,6 +27,7 @@ show up in /proc/sys/kernel:
+ - domainname
+ - hostname
+ - hotplug
++- iso_cpu
+ - java-appletviewer [ binfmt_java, obsolete ]
+ - java-interpreter [ binfmt_java, obsolete ]
+ - kstack_depth_to_print [ X86 only ]
+@@ -49,6 +50,7 @@ show up in /proc/sys/kernel:
+ - randomize_va_space
+ - real-root-dev ==> Documentation/initrd.txt
+ - reboot-cmd [ SPARC only ]
++- rr_interval
+ - rtsig-max
+ - rtsig-nr
+ - sem
+@@ -171,6 +173,16 @@ Default value is "/sbin/hotplug".
+
+ ==============================================================
+
++iso_cpu: (BFS 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
+@@ -333,6 +345,19 @@ rebooting. ???
+
+ ==============================================================
+
++rr_interval: (BFS 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. 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 1-5000.
++
++==============================================================
++
+ rtsig-max & rtsig-nr:
+
+ The file rtsig-max can be used to tune the maximum number
+--- a/include/linux/init_task.h
++++ b/include/linux/init_task.h
+@@ -116,9 +116,10 @@ extern struct cred init_cred;
+ .usage = ATOMIC_INIT(2), \
+ .flags = PF_KTHREAD, \
+ .lock_depth = -1, \
+- .prio = MAX_PRIO-20, \
++ .prio = NORMAL_PRIO, \
+ .static_prio = MAX_PRIO-20, \
+- .normal_prio = MAX_PRIO-20, \
++ .normal_prio = NORMAL_PRIO, \
++ .deadline = 0, \
+ .policy = SCHED_NORMAL, \
+ .cpus_allowed = CPU_MASK_ALL, \
+ .mm = NULL, \
+--- a/include/linux/sched.h
++++ b/include/linux/sched.h
+@@ -36,9 +36,12 @@
+ #define SCHED_FIFO 1
+ #define SCHED_RR 2
+ #define SCHED_BATCH 3
+-/* SCHED_ISO: reserved but not implemented yet */
++#define SCHED_ISO 4
+ #define SCHED_IDLE 5
+
++#define SCHED_MAX (SCHED_IDLE)
++#define SCHED_RANGE(policy) ((policy) <= SCHED_MAX)
++
+ #ifdef __KERNEL__
+
+ struct sched_param {
+@@ -1090,10 +1093,13 @@ struct sched_entity {
+ struct load_weight load; /* for load-balancing */
+ struct rb_node run_node;
+ struct list_head group_node;
++#ifdef CONFIG_SCHED_CFS
+ unsigned int on_rq;
+
+ u64 exec_start;
++#endif
+ u64 sum_exec_runtime;
++#ifdef CONFIG_SCHED_CFS
+ u64 vruntime;
+ u64 prev_sum_exec_runtime;
+
+@@ -1145,6 +1151,7 @@ struct sched_entity {
+ /* rq "owned" by this entity/group: */
+ struct cfs_rq *my_q;
+ #endif
++#endif
+ };
+
+ struct sched_rt_entity {
+@@ -1172,17 +1179,19 @@ struct task_struct {
+
+ int lock_depth; /* BKL lock depth */
+
+-#ifdef CONFIG_SMP
+-#ifdef __ARCH_WANT_UNLOCKED_CTXSW
+ int oncpu;
+-#endif
+-#endif
+-
+ int prio, static_prio, normal_prio;
+ unsigned int rt_priority;
+ const struct sched_class *sched_class;
+ struct sched_entity se;
+ struct sched_rt_entity rt;
++ unsigned long deadline;
++#ifdef CONFIG_SCHED_BFS
++ int load_weight; /* for niceness load balancing purposes */
++ int first_time_slice;
++ unsigned long long timestamp, last_ran;
++ unsigned long utime_pc, stime_pc;
++#endif
+
+ #ifdef CONFIG_PREEMPT_NOTIFIERS
+ /* list of struct preempt_notifier: */
+@@ -1205,6 +1214,9 @@ struct task_struct {
+
+ unsigned int policy;
+ cpumask_t cpus_allowed;
++#ifdef CONFIG_HOTPLUG_CPU
++ cpumask_t unplugged_mask;
++#endif
+
+ #ifdef CONFIG_PREEMPT_RCU
+ int rcu_read_lock_nesting;
+@@ -1497,11 +1509,19 @@ struct task_struct {
+ * priority to a value higher than any user task. Note:
+ * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO.
+ */
+-
++#define PRIO_RANGE (40)
+ #define MAX_USER_RT_PRIO 100
+ #define MAX_RT_PRIO MAX_USER_RT_PRIO
+-
++#ifdef CONFIG_SCHED_BFS
++#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
+ #define MAX_PRIO (MAX_RT_PRIO + 40)
++#define NORMAL_PRIO (MAX_RT_PRIO - 20)
++#endif
+ #define DEFAULT_PRIO (MAX_RT_PRIO + 20)
+
+ static inline int rt_prio(int prio)
+@@ -1785,7 +1805,7 @@ task_sched_runtime(struct task_struct *t
+ 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_CFS)
+ extern void sched_exec(void);
+ #else
+ #define sched_exec() {}
+--- a/init/Kconfig
++++ b/init/Kconfig
+@@ -441,9 +441,22 @@ config LOG_BUF_SHIFT
+ config HAVE_UNSTABLE_SCHED_CLOCK
+ bool
+
++choice
++ prompt "Scheduler"
++ default SCHED_CFS
++
++ config SCHED_CFS
++ bool "CFS"
++
++ config SCHED_BFS
++ bool "BFS"
++
++endchoice
++
+ config GROUP_SCHED
+ bool "Group CPU scheduler"
+ depends on EXPERIMENTAL
++ depends on SCHED_CFS
+ default n
+ help
+ This feature lets CPU scheduler recognize task groups and control CPU
+@@ -494,6 +507,7 @@ endchoice
+
+ menuconfig CGROUPS
+ boolean "Control Group support"
++ depends on SCHED_CFS
+ help
+ This option adds support for grouping sets of processes together, for
+ use with process control subsystems such as Cpusets, CFS, memory
+--- a/kernel/Makefile
++++ b/kernel/Makefile
+@@ -2,7 +2,7 @@
+ # Makefile for the linux kernel.
+ #
+
+-obj-y = sched.o fork.o exec_domain.o panic.o printk.o \
++obj-y = $(if $(CONFIG_SCHED_CFS),sched.o,sched_bfs.o) fork.o exec_domain.o panic.o printk.o \
+ cpu.o exit.o itimer.o time.o softirq.o resource.o \
+ sysctl.o capability.o ptrace.o timer.o user.o \
+ signal.o sys.o kmod.o workqueue.o pid.o \
+@@ -108,6 +108,7 @@ ifneq ($(CONFIG_SCHED_OMIT_FRAME_POINTER
+ # I turn this off for IA-64 only. Andreas Schwab says it's also needed on m68k
+ # to get a correct value for the wait-channel (WCHAN in ps). --davidm
+ CFLAGS_sched.o := $(PROFILING) -fno-omit-frame-pointer
++CFLAGS_sched_bfs.o := $(PROFILING) -fno-omit-frame-pointer
+ endif
+
+ $(obj)/configs.o: $(obj)/config_data.h
+--- a/kernel/kthread.c
++++ b/kernel/kthread.c
+@@ -16,7 +16,11 @@
+ #include <linux/mutex.h>
+ #include <trace/events/sched.h>
+
++#ifdef CONFIG_SCHED_BFS
++#define KTHREAD_NICE_LEVEL (0)
++#else
+ #define KTHREAD_NICE_LEVEL (-5)
++#endif
+
+ static DEFINE_SPINLOCK(kthread_create_lock);
+ static LIST_HEAD(kthread_create_list);
+--- /dev/null
++++ b/kernel/sched_bfs.c
+@@ -0,0 +1,6105 @@
++/*
++ * 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_counter.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/kthread.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/reciprocal_div.h>
++#include <linux/log2.h>
++#include <linux/bootmem.h>
++#include <linux/ftrace.h>
++
++#include <asm/tlb.h>
++#include <asm/unistd.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_IDLE)
++#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)
++
++/* Some helpers for converting to/from various scales.*/
++#define JIFFIES_TO_NS(TIME) ((TIME) * (1000000000 / HZ))
++#define MS_TO_NS(TIME) ((TIME) * 1000000)
++#define MS_TO_US(TIME) ((TIME) * 1000)
++
++#ifdef CONFIG_SMP
++/*
++ * Divide a load by a sched group cpu_power : (load / sg->__cpu_power)
++ * Since cpu_power is a 'constant', we can use a reciprocal divide.
++ */
++static inline u32 sg_div_cpu_power(const struct sched_group *sg, u32 load)
++{
++ return reciprocal_divide(load, sg->reciprocal_cpu_power);
++}
++
++/*
++ * Each time a sched group cpu_power is changed,
++ * we must compute its reciprocal value
++ */
++static inline void sg_inc_cpu_power(struct sched_group *sg, u32 val)
++{
++ sg->__cpu_power += val;
++ sg->reciprocal_cpu_power = reciprocal_value(sg->__cpu_power);
++}
++#endif
++
++/*
++ * 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;
++
++int prio_ratios[PRIO_RANGE] __read_mostly;
++
++static inline unsigned long timeslice(void)
++{
++ return MS_TO_US(rr_interval);
++}
++
++struct global_rq {
++ 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);
++ unsigned long iso_ticks;
++ unsigned short iso_refractory;
++#ifdef CONFIG_SMP
++ unsigned long qnr; /* queued not running */
++ cpumask_t cpu_idle_map;
++#endif
++};
++
++static struct global_rq grq;
++
++/*
++ * This is the main, per-CPU runqueue data structure.
++ * All this is protected by the global_rq lock.
++ */
++struct rq {
++#ifdef CONFIG_SMP
++#ifdef CONFIG_NO_HZ
++ unsigned char in_nohz_recently;
++#endif
++#endif
++
++ struct task_struct *curr, *idle;
++ struct mm_struct *prev_mm;
++ struct list_head queue; /* Place to store currently running task */
++
++ /* Stored data about rq->curr to work outside grq lock */
++ unsigned long rq_deadline;
++ unsigned int rq_policy;
++ int rq_time_slice;
++ int rq_prio;
++
++ /* 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;
++
++ int cpu; /* cpu of this runqueue */
++ int online;
++
++#ifdef CONFIG_SMP
++ struct root_domain *rd;
++ struct sched_domain *sd;
++
++ struct list_head migration_queue;
++#endif
++
++ u64 clock;
++#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
++
++/*
++ * 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;
++#if defined(CONFIG_SCHED_MC) || defined(CONFIG_SCHED_SMT)
++ /*
++ * Preferred wake up cpu nominated by sched_mc balance that will be
++ * used when most cpus are idle in the system indicating overall very
++ * low system utilisation. Triggered at POWERSAVINGS_BALANCE_WAKEUP(2)
++ */
++ unsigned int sched_mc_preferred_wakeup_cpu;
++#endif
++};
++
++/*
++ * 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;
++
++#endif
++
++static inline int cpu_of(struct rq *rq)
++{
++#ifdef CONFIG_SMP
++ return rq->cpu;
++#else
++ return 0;
++#endif
++}
++
++/*
++ * 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(cpu_rq(cpu)->sd); __sd; __sd = __sd->parent)
++
++#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)
++
++#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
++
++inline void update_rq_clock(struct rq *rq)
++{
++ rq->clock = sched_clock_cpu(cpu_of(rq));
++}
++
++static inline int task_running(struct task_struct *p)
++{
++ return (!!p->oncpu);
++}
++
++static inline void grq_lock(void)
++ __acquires(grq.lock)
++{
++ smp_mb();
++ spin_lock(&grq.lock);
++}
++
++static inline void grq_unlock(void)
++ __releases(grq.lock)
++{
++ spin_unlock(&grq.lock);
++}
++
++static inline void grq_lock_irq(void)
++ __acquires(grq.lock)
++{
++ smp_mb();
++ spin_lock_irq(&grq.lock);
++}
++
++static inline void time_lock_grq(struct rq *rq)
++ __acquires(grq.lock)
++{
++ grq_lock();
++ update_rq_clock(rq);
++}
++
++static inline void grq_unlock_irq(void)
++ __releases(grq.lock)
++{
++ spin_unlock_irq(&grq.lock);
++}
++
++static inline void grq_lock_irqsave(unsigned long *flags)
++ __acquires(grq.lock)
++{
++ smp_mb();
++ spin_lock_irqsave(&grq.lock, *flags);
++}
++
++static inline void grq_unlock_irqrestore(unsigned long *flags)
++ __releases(grq.lock)
++{
++ 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_rq_clock(rq);
++ return rq;
++}
++
++static inline void task_grq_unlock(unsigned long *flags)
++ __releases(grq.lock)
++{
++ grq_unlock_irqrestore(flags);
++}
++
++/**
++ * runqueue_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.
++ */
++int runqueue_is_locked(void)
++{
++ return spin_is_locked(&grq.lock);
++}
++
++void task_rq_unlock_wait(struct task_struct *p)
++ __releases(grq.lock)
++{
++ smp_mb(); /* spin-unlock-wait is not a full memory barrier */
++ spin_unlock_wait(&grq.lock);
++}
++
++static inline void time_grq_lock(struct rq *rq, unsigned long *flags)
++ __acquires(grq.lock)
++{
++ spin_lock_irqsave(&grq.lock, *flags);
++ update_rq_clock(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();
++}
++
++#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 */
++
++/*
++ * A task that is queued 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 and be queued
++ * temporarily in its own rq queue.
++ * A task that is running and no longer queued will be seen only on
++ * context switch exit.
++ */
++
++static inline int task_queued(struct task_struct *p)
++{
++ return (!list_empty(&p->rt.run_list));
++}
++
++static inline int task_queued_only(struct task_struct *p)
++{
++ return (!list_empty(&p->rt.run_list) && !task_running(p));
++}
++
++/*
++ * Removing from the global runqueue. Enter with grq locked.
++ */
++static void dequeue_task(struct task_struct *p)
++{
++ list_del_init(&p->rt.run_list);
++ if (list_empty(grq.queue + p->prio))
++ __clear_bit(p->prio, grq.prio_bitmap);
++}
++
++static inline void reset_first_time_slice(struct task_struct *p)
++{
++ if (unlikely(p->first_time_slice))
++ p->first_time_slice = 0;
++}
++
++static int idleprio_suitable(struct task_struct *p)
++{
++ return (!freezing(p) && !signal_pending(p) &&
++ !(task_contributes_to_load(p)) && !(p->flags & (PF_EXITING)));
++}
++
++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->rt.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->rt.run_list, grq.queue + p->prio);
++ sched_info_queued(p);
++}
++
++static inline void requeue_task(struct task_struct *p)
++{
++ sched_info_queued(p);
++}
++
++static inline int pratio(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.
++ */
++static inline int task_timeslice(struct task_struct *p)
++{
++ return (rr_interval * pratio(p) / 100);
++}
++
++#ifdef CONFIG_SMP
++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;
++}
++#else
++static inline void inc_qnr(void)
++{
++}
++
++static inline void dec_qnr(void)
++{
++}
++
++static inline int queued_notrunning(void)
++{
++ return grq.nr_running;
++}
++#endif
++
++/*
++ * 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. The rq
++ * doesn't really matter but gives us the local clock.
++ */
++static void activate_task(struct task_struct *p, struct rq *rq)
++{
++ u64 now = rq->clock;
++
++ /*
++ * 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),
++ (now - p->timestamp) >> 20);
++ }
++
++ p->prio = effective_prio(p);
++ p->timestamp = now;
++ 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.
++ */
++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);
++ /*
++ * 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, rq->cpu);
++ dequeue_task(p);
++ list_add(&p->rt.run_list, &rq->queue);
++ 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)
++{
++ list_del_init(&p->rt.run_list);
++ 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_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_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 list_head list;
++
++ struct task_struct *task;
++ int dest_cpu;
++
++ struct completion done;
++};
++
++/*
++ * wait_task_context_switch - wait for a thread to complete at least one
++ * context switch.
++ *
++ * @p must not be current.
++ */
++void wait_task_context_switch(struct task_struct *p)
++{
++ unsigned long nvcsw, nivcsw, flags;
++ int running;
++ struct rq *rq;
++
++ nvcsw = p->nvcsw;
++ nivcsw = p->nivcsw;
++ for (;;) {
++ /*
++ * The runqueue is assigned before the actual context
++ * switch. We need to take the runqueue lock.
++ *
++ * We could check initially without the lock but it is
++ * very likely that we need to take the lock in every
++ * iteration.
++ */
++ rq = task_grq_lock(p, &flags);
++ running = task_running(p);
++ task_grq_unlock(&flags);
++
++ if (likely(!running))
++ break;
++ /*
++ * The switch count is incremented before the actual
++ * context switch. We thus wait for two switches to be
++ * sure at least one completed.
++ */
++ if ((p->nvcsw - nvcsw) > 1)
++ break;
++ if ((p->nivcsw - nivcsw) > 1)
++ break;
++
++ cpu_relax();
++ }
++}
++
++/*
++ * 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!
++ */
++ rq = task_rq(p);
++
++ /*
++ * 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(rq, 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_BATCH and SCHED_IDLE don't preempt,
++ * they cooperatively multitask.
++ */
++static inline int task_preempts_curr(struct task_struct *p, struct rq *rq)
++{
++ int preempts = 0;
++
++ if (p->prio < rq->rq_prio)
++ preempts = 1;
++ else if (p->policy == SCHED_NORMAL && (p->prio == rq->rq_prio &&
++ time_before(p->deadline, rq->rq_deadline)))
++ preempts = 1;
++ return preempts;
++}
++
++/*
++ * Wake up *any* suitable cpu to schedule this task.
++ */
++static void try_preempt(struct task_struct *p)
++{
++ struct rq *highest_prio_rq, *this_rq;
++ unsigned long latest_deadline, cpu;
++ int highest_prio;
++ cpumask_t tmp;
++
++ /* Try the task's previous rq first and as a fallback */
++ this_rq = task_rq(p);
++
++ if (cpu_isset(this_rq->cpu, p->cpus_allowed)) {
++ highest_prio_rq = this_rq;
++ /* If this_rq is idle, use that. */
++ if (rq_idle(this_rq))
++ goto found_rq;
++ } else
++ highest_prio_rq = cpu_rq(any_online_cpu(p->cpus_allowed));
++ latest_deadline = this_rq->rq_deadline;
++ highest_prio = this_rq->rq_prio;
++
++ cpus_and(tmp, cpu_online_map, p->cpus_allowed);
++
++ for_each_cpu_mask(cpu, tmp) {
++ struct rq *rq;
++ int rq_prio;
++
++ rq = cpu_rq(cpu);
++
++ if (rq_idle(rq)) {
++ /* found an idle rq, use that one */
++ highest_prio_rq = rq;
++ goto found_rq;
++ }
++
++ rq_prio = rq->rq_prio;
++ if (rq_prio > highest_prio ||
++ (rq_prio == highest_prio &&
++ time_after(rq->rq_deadline, latest_deadline))) {
++ highest_prio = rq_prio;
++ latest_deadline = rq->rq_deadline;
++ highest_prio_rq = rq;
++ }
++ }
++
++ if (!task_preempts_curr(p, highest_prio_rq))
++ return;
++found_rq:
++ resched_task(highest_prio_rq->curr);
++ return;
++}
++
++/**
++ * 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();
++}
++
++#ifdef CONFIG_SMP
++static int suitable_idle_cpus(struct task_struct *p)
++{
++ return (cpus_intersects(p->cpus_allowed, grq.cpu_idle_map));
++}
++#else
++static int suitable_idle_cpus(struct task_struct *p)
++{
++ return 0;
++}
++#endif
++
++/***
++ * try_to_wake_up - wake up a thread
++ * @p: the to-be-woken-up thread
++ * @state: the mask of task states that can be woken
++ * @sync: do a synchronous wakeup?
++ *
++ * 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 failure only if the task is already active.
++ */
++static int try_to_wake_up(struct task_struct *p, unsigned int state, int sync)
++{
++ unsigned long flags;
++ int success = 0;
++ long old_state;
++ struct rq *rq;
++
++ rq = time_task_grq_lock(p, &flags);
++ old_state = p->state;
++ if (!(old_state & state))
++ goto out_unlock;
++
++ /*
++ * Note this catches tasks that are running and queued, but returns
++ * false during the context switch when they're running and no
++ * longer queued.
++ */
++ if (task_queued(p))
++ goto out_running;
++
++ 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 (!sync || (sync && suitable_idle_cpus(p)))
++ try_preempt(p);
++ success = 1;
++
++out_running:
++ trace_sched_wakeup(rq, p, success);
++ p->state = TASK_RUNNING;
++out_unlock:
++ task_grq_unlock(&flags);
++ return 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);
++}
++
++/*
++ * 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)
++{
++ 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, but have not actually
++ * inserted it onto the runqueue yet. 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->se.sum_exec_runtime = p->stime_pc = p->utime_pc = 0;
++
++ /*
++ * Make sure we do not leak PI boosting priority to the child:
++ */
++ p->prio = current->normal_prio;
++
++ INIT_LIST_HEAD(&p->rt.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.
++ */
++ local_irq_disable();
++ rq = task_rq(current);
++ if (likely(rq->rq_time_slice > 0)) {
++ rq->rq_time_slice /= 2;
++ /*
++ * The remainder of the first timeslice might be recovered by
++ * the parent if the child exits early enough.
++ */
++ p->first_time_slice = 1;
++ }
++ p->rt.time_slice = rq->rq_time_slice;
++ local_irq_enable();
++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 = time_task_grq_lock(p, &flags); ;
++ parent = p->parent;
++ BUG_ON(p->state != TASK_RUNNING);
++ set_task_cpu(p, task_cpu(parent));
++
++ activate_task(p, rq);
++ trace_sched_wakeup_new(rq, 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);
++ task_grq_unlock(&flags);
++}
++
++/*
++ * Potentially available exiting-child timeslices are
++ * retrieved here - this way the parent does not get
++ * penalized for creating too many threads.
++ *
++ * (this cannot be used to 'generate' timeslices
++ * artificially, because any timeslice recovered here
++ * was given away by the parent in the first place.)
++ */
++void sched_exit(struct task_struct *p)
++{
++ struct task_struct *parent;
++ unsigned long flags;
++ struct rq *rq;
++
++ if (p->first_time_slice) {
++ parent = p->parent;
++ rq = task_grq_lock(parent, &flags);
++ parent->rt.time_slice += p->rt.time_slice;
++ if (unlikely(parent->rt.time_slice > timeslice()))
++ parent->rt.time_slice = timeslice();
++ 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);
++ perf_counter_task_sched_in(current, cpu_of(rq));
++ 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(rq, 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_enter_lazy_cpu_mode();
++
++ if (unlikely(!mm)) {
++ next->active_mm = oldmm;
++ atomic_inc(&oldmm->mm_count);
++ enter_lazy_tlb(oldmm, next);
++ } else
++ switch_mm(oldmm, mm, next);
++
++ if (unlikely(!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)
++{
++ unsigned 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_active(void)
++{
++ return nr_running() + nr_uninterruptible();
++}
++
++/* 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(void)
++{
++ 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);
++
++/*
++ * 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(jiffies_to_cputime(1));
++
++ 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 = jiffies_to_cputime(1);
++ cputime_t one_jiffy_scaled = cputime_to_scaled(one_jiffy);
++ cputime64_t tmp = cputime_to_cputime64(one_jiffy);
++
++ p->stime_pc += pc;
++ if (p->stime_pc >= 100) {
++ p->stime_pc -= 100;
++ p->stime = cputime_add(p->stime, one_jiffy);
++ p->stimescaled = cputime_add(p->stimescaled, one_jiffy_scaled);
++ account_group_system_time(p, one_jiffy);
++ acct_update_integrals(p);
++ }
++ p->se.sum_exec_runtime += ns;
++
++ if (hardirq_count() - hardirq_offset)
++ rq->irq_pc += pc;
++ else if (softirq_count()) {
++ 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 = jiffies_to_cputime(1);
++ cputime_t one_jiffy_scaled = cputime_to_scaled(one_jiffy);
++ cputime64_t tmp = cputime_to_cputime64(one_jiffy);
++
++ p->utime_pc += pc;
++ if (p->utime_pc >= 100) {
++ p->utime_pc -= 100;
++ p->utime = cputime_add(p->utime, one_jiffy);
++ p->utimescaled = cputime_add(p->utimescaled, one_jiffy_scaled);
++ account_group_user_time(p, one_jiffy);
++ acct_update_integrals(p);
++ }
++ p->se.sum_exec_runtime += 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 / JIFFIES_TO_NS(1))
++
++/*
++ * This is called on clock ticks and on context switches.
++ * Bank in p->se.sum_exec_runtime the ns elapsed since the last tick or switch.
++ * CPU scheduler quota accounting is also performed here in microseconds.
++ * The value returned from sched_clock() occasionally gives bogus values so
++ * some sanity checking is required. Time is supposed to be banked all the
++ * time so default to half a tick to make up for when sched_clock reverts
++ * to just returning jiffies, and for hardware that can't do tsc.
++ */
++static void
++update_cpu_clock(struct rq *rq, struct task_struct *p, int tick)
++{
++ long time_diff = rq->clock - p->last_ran;
++ long account_ns = rq->clock - rq->timekeep_clock;
++ struct task_struct *idle = rq->idle;
++ unsigned long account_pc;
++
++ /*
++ * There should be less than or equal to one jiffy worth, and not
++ * negative/overflow. time_diff is only used for internal scheduler
++ * time_slice accounting.
++ */
++ if (time_diff <= 0)
++ time_diff = JIFFIES_TO_NS(1) / 2;
++ else if (time_diff > JIFFIES_TO_NS(1))
++ time_diff = JIFFIES_TO_NS(1);
++
++ 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)
++ rq->rq_time_slice -= time_diff / 1000;
++ p->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 on @rq.
++ */
++static u64 do_task_delta_exec(struct task_struct *p, struct rq *rq)
++{
++ u64 ns = 0;
++
++ if (p == rq->curr) {
++ update_rq_clock(rq);
++ ns = rq->clock - p->last_ran;
++ if ((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 = 0;
++
++ 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 = 0;
++
++ rq = task_grq_lock(p, &flags);
++ ns = p->se.sum_exec_runtime + 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. */
++ 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
++
++/*
++ * 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 grq_lock
++ * because the occasional inaccurate result won't matter. However the
++ * data is only ever modified under lock.
++ */
++static void set_iso_refractory(void)
++{
++ grq_lock();
++ grq.iso_refractory = 1;
++ grq_unlock();
++}
++
++static void clear_iso_refractory(void)
++{
++ grq_lock();
++ grq.iso_refractory = 0;
++ grq_unlock();
++}
++
++/*
++ * 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.
++ */
++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 * 90 / 100))
++ clear_iso_refractory();
++ }
++ return grq.iso_refractory;
++}
++
++static void iso_tick(void)
++{
++ grq_lock();
++ grq.iso_ticks += 100;
++ grq_unlock();
++}
++
++/* No SCHED_ISO task was running so decrease rq->iso_ticks */
++static inline void no_iso_tick(void)
++{
++ if (grq.iso_ticks) {
++ grq_lock();
++ grq.iso_ticks = grq.iso_ticks * (ISO_PERIOD - 1) / ISO_PERIOD;
++ grq_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_idle(rq) || rq->rq_time_slice > 0 || rq->rq_policy == SCHED_FIFO)
++ return;
++
++ /* p->rt.time_slice <= 0. We only modify task_struct under grq lock */
++ grq_lock();
++ p = rq->curr;
++ if (likely(task_running(p))) {
++ requeue_task(p);
++ 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 = smp_processor_id();
++ struct rq *rq = cpu_rq(cpu);
++
++ sched_clock_tick();
++ update_rq_clock(rq);
++ update_cpu_clock(rq, rq->curr, 1);
++ if (!rq_idle(rq))
++ task_running_tick(rq);
++ else {
++ no_iso_tick();
++ if (unlikely(queued_notrunning()))
++ set_tsk_need_resched(rq->idle);
++ }
++}
++
++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 jiffies + (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.
++ */
++static inline int prio_deadline_diff(struct task_struct *p)
++{
++ return (pratio(p) * rr_interval * HZ / 1000 / 100) ? : 1;
++}
++
++static inline int longest_deadline(void)
++{
++ return (prio_ratios[39] * rr_interval * HZ / 1000 / 100);
++}
++
++/*
++ * SCHED_IDLE tasks still have a deadline set, but offset by to nice +19.
++ * This allows nice levels to work between IDLEPRIO tasks and gives a
++ * deadline longer than nice +19 for when they're scheduled as SCHED_NORMAL
++ * tasks.
++ */
++static inline void time_slice_expired(struct task_struct *p)
++{
++ reset_first_time_slice(p);
++ p->rt.time_slice = timeslice();
++ p->deadline = jiffies + prio_deadline_diff(p);
++ if (idleprio_task(p))
++ p->deadline += longest_deadline();
++}
++
++static inline void check_deadline(struct task_struct *p)
++{
++ if (p->rt.time_slice <= 0)
++ 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)
++{
++ unsigned long dl, earliest_deadline = 0; /* Initialise to silence compiler */
++ struct task_struct *p, *edt;
++ unsigned int cpu = rq->cpu;
++ struct list_head *queue;
++ int idx = 0;
++
++ edt = idle;
++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, rt.run_list) {
++ /* Make sure cpu affinity is ok */
++ if (!cpu_isset(cpu, p->cpus_allowed))
++ continue;
++ if (idx < MAX_RT_PRIO) {
++ /* We found an rt task */
++ edt = p;
++ goto out_take;
++ }
++
++ /*
++ * No rt task, select the earliest deadline task now.
++ * On the 1st run the 2nd condition is never used, so
++ * there is no need to initialise earliest_deadline
++ * before. Normalise all old deadlines to now.
++ */
++ if (time_before(p->deadline, jiffies))
++ dl = jiffies;
++ else
++ dl = p->deadline;
++
++ if (edt == idle ||
++ time_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;
++}
++
++#ifdef CONFIG_SMP
++static inline void set_cpuidle_map(unsigned long cpu)
++{
++ cpu_set(cpu, grq.cpu_idle_map);
++}
++
++static inline void clear_cpuidle_map(unsigned long cpu)
++{
++ cpu_clear(cpu, grq.cpu_idle_map);
++}
++
++#else /* CONFIG_SMP */
++static inline void set_cpuidle_map(unsigned long cpu)
++{
++}
++
++static inline void clear_cpuidle_map(unsigned long cpu)
++{
++}
++#endif /* !CONFIG_SMP */
++
++/*
++ * 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
++}
++
++/*
++ * schedule() is the main scheduler function.
++ */
++asmlinkage void __sched __schedule(void)
++{
++ struct task_struct *prev, *next, *idle;
++ int deactivate = 0, cpu;
++ long *switch_count;
++ struct rq *rq;
++ u64 now;
++
++ cpu = smp_processor_id();
++ rq = this_rq();
++ rcu_qsctr_inc(cpu);
++ prev = rq->curr;
++ switch_count = &prev->nivcsw;
++
++ release_kernel_lock(prev);
++need_resched_nonpreemptible:
++
++ schedule_debug(prev);
++ idle = rq->idle;
++ /*
++ * The idle thread is not allowed to schedule!
++ * Remove this check after it has been exercised a bit.
++ */
++ if (unlikely(prev == idle) && prev->state != TASK_RUNNING) {
++ printk(KERN_ERR "bad: scheduling from the idle thread!\n");
++ dump_stack();
++ }
++
++ grq_lock_irq();
++ update_rq_clock(rq);
++ now = rq->clock;
++ update_cpu_clock(rq, prev, 0);
++
++ clear_tsk_need_resched(prev);
++
++ if (prev->state && !(preempt_count() & PREEMPT_ACTIVE)) {
++ if (unlikely(signal_pending_state(prev->state, prev)))
++ prev->state = TASK_RUNNING;
++ else
++ deactivate = 1;
++ switch_count = &prev->nvcsw;
++ }
++
++ if (prev != idle) {
++ /* Update all the information stored on struct rq */
++ prev->rt.time_slice = rq->rq_time_slice;
++ prev->deadline = rq->rq_deadline;
++ check_deadline(prev);
++ return_task(prev, deactivate);
++ }
++
++ if (likely(queued_notrunning())) {
++ next = earliest_deadline_task(rq, idle);
++ } else {
++ next = idle;
++ schedstat_inc(rq, sched_goidle);
++ }
++
++ if (next == rq->idle)
++ set_cpuidle_map(cpu);
++ else
++ clear_cpuidle_map(cpu);
++
++ prefetch(next);
++ prefetch_stack(next);
++
++ prev->timestamp = prev->last_ran = now;
++
++ if (likely(prev != next)) {
++ rq->rq_time_slice = next->rt.time_slice;
++ rq->rq_deadline = next->deadline;
++ rq->rq_prio = next->prio;
++
++ sched_info_switch(prev, next);
++ grq.nr_switches++;
++ next->oncpu = 1;
++ prev->oncpu = 0;
++ rq->curr = next;
++ ++*switch_count;
++
++ context_switch(rq, prev, next); /* unlocks the rq */
++ /*
++ * the context switch might have flipped the stack from under
++ * us, hence refresh the local variables.
++ */
++ cpu = smp_processor_id();
++ rq = cpu_rq(cpu);
++ } else
++ grq_unlock_irq();
++
++ if (unlikely(reacquire_kernel_lock(current) < 0))
++ goto need_resched_nonpreemptible;
++}
++
++asmlinkage void __sched schedule(void)
++{
++need_resched:
++ preempt_disable();
++ __schedule();
++ preempt_enable_no_resched();
++ if (unlikely(test_thread_flag(TIF_NEED_RESCHED)))
++ goto need_resched;
++}
++EXPORT_SYMBOL(schedule);
++
++#ifdef CONFIG_SMP
++int mutex_spin_on_owner(struct mutex *lock, struct thread_info *owner)
++{
++ return 0;
++}
++#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 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(PREEMPT_ACTIVE);
++ schedule();
++ sub_preempt_count(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 sync,
++ void *key)
++{
++ return try_to_wake_up(curr->private, mode, sync);
++}
++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.
++ */
++void __wake_up_common(wait_queue_head_t *q, unsigned int mode,
++ int nr_exclusive, int sync, 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 flags = curr->flags;
++
++ if (curr->func(curr, mode, sync, 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);
++}
++
++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 'synchronized'
++ * 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 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, 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 'synchronized'
++ * 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);
++
++ wait.flags |= WQ_FLAG_EXCLUSIVE;
++ __add_wait_queue_tail(&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);
++
++/**
++ * 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)
++{
++ int ret = 1;
++
++ spin_lock_irq(&x->wait.lock);
++ if (!x->done)
++ ret = 0;
++ else
++ x->done--;
++ spin_unlock_irq(&x->wait.lock);
++ 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)
++{
++ int ret = 1;
++
++ spin_lock_irq(&x->wait.lock);
++ if (!x->done)
++ ret = 0;
++ spin_unlock_irq(&x->wait.lock);
++ 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 = time_task_grq_lock(p, &flags);
++
++ oldprio = p->prio;
++ queued = task_queued_only(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);
++ }
++
++ task_grq_unlock(&flags);
++}
++
++#endif
++
++/*
++ * Adjust the deadline for when the priority is to change, before it's
++ * changed.
++ */
++static void adjust_deadline(struct task_struct *p, int new_prio)
++{
++ p->deadline += (prio_ratios[USER_PRIO(new_prio)] - pratio(p)) *
++ rr_interval * HZ / 1000 / 100;
++}
++
++void set_user_nice(struct task_struct *p, long nice)
++{
++ int queued, new_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_only(p);
++ /*
++ * If p is actually running, we don't need to do anything when
++ * changing the priority because the grq is unaffected.
++ */
++ if (queued)
++ dequeue_task(p);
++
++ adjust_deadline(p, new_static);
++ p->static_prio = new_static;
++ p->prio = effective_prio(p);
++
++ if (queued) {
++ enqueue_task(p);
++ try_preempt(p);
++ }
++
++ /* Just resched the task, schedule() will know what to do. */
++ if (task_running(p))
++ 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 <= p->signal->rlim[RLIMIT_NICE].rlim_cur ||
++ 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_IDLE).
++ */
++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;
++
++ delta = (p->deadline - jiffies) * 40 / longest_deadline();
++ if (delta > 0 && delta <= 80)
++ prio += delta;
++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, int policy, int prio)
++{
++ BUG_ON(task_queued_only(p));
++
++ p->policy = policy;
++ p->rt_priority = prio;
++ p->normal_prio = normal_prio(p);
++ /* we are holding p->pi_lock already */
++ p->prio = rt_mutex_getprio(p);
++ /*
++ * Reschedule if running. schedule() will know if it can continue
++ * running or not.
++ */
++ if (task_running(p))
++ 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, oldprio, oldpolicy = -1;
++ unsigned long flags, rlim_rtprio = 0;
++ 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 = p->signal->rlim[RLIMIT_RTPRIO].rlim_cur;
++ 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)
++ policy = oldpolicy = p->policy;
++ else 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)) {
++ /* 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_IDLE)
++ return -EPERM;
++ break;
++ case SCHED_IDLE:
++ if (policy == SCHED_IDLE)
++ goto out;
++ return -EPERM;
++ default:
++ break;
++ }
++ }
++
++ /* can't change other user's priorities */
++ if (!check_same_owner(p))
++ return -EPERM;
++ }
++
++ retval = security_task_setscheduler(p, policy, param);
++ if (retval)
++ return retval;
++ /*
++ * make sure no PI-waiters arrive (or leave) while we are
++ * changing the priority of the task:
++ */
++ 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);
++ /* recheck policy now with rq lock held */
++ if (unlikely(oldpolicy != -1 && oldpolicy != p->policy)) {
++ __task_grq_unlock();
++ spin_unlock_irqrestore(&p->pi_lock, flags);
++ policy = oldpolicy = -1;
++ goto recheck;
++ }
++ update_rq_clock(rq);
++ queued = task_queued_only(p);
++ if (queued)
++ dequeue_task(p);
++ oldprio = p->prio;
++ __setscheduler(p, policy, param->sched_priority);
++ if (queued) {
++ enqueue_task(p);
++ try_preempt(p);
++ }
++ __task_grq_unlock();
++ 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;
++ read_lock(&tasklist_lock);
++ p = find_process_by_pid(pid);
++ if (p) {
++ retval = security_task_getscheduler(p);
++ if (!retval)
++ retval = p->policy;
++ }
++ read_unlock(&tasklist_lock);
++
++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;
++
++ read_lock(&tasklist_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;
++ read_unlock(&tasklist_lock);
++
++ /*
++ * 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:
++ read_unlock(&tasklist_lock);
++ 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();
++ read_lock(&tasklist_lock);
++
++ p = find_process_by_pid(pid);
++ if (!p) {
++ read_unlock(&tasklist_lock);
++ put_online_cpus();
++ return -ESRCH;
++ }
++
++ /*
++ * It is not safe to call set_cpus_allowed with the
++ * tasklist_lock held. We will bump the task_struct's
++ * usage count and then drop tasklist_lock.
++ */
++ get_task_struct(p);
++ read_unlock(&tasklist_lock);
++
++ 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, 0, NULL);
++ 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;
++ int retval;
++
++ mutex_lock(&sched_hotcpu_mutex);
++ read_lock(&tasklist_lock);
++
++ retval = -ESRCH;
++ p = find_process_by_pid(pid);
++ if (!p)
++ goto out_unlock;
++
++ retval = security_task_getscheduler(p);
++ if (retval)
++ goto out_unlock;
++
++ cpus_and(*mask, p->cpus_allowed, cpu_online_map);
++
++out_unlock:
++ read_unlock(&tasklist_lock);
++ mutex_unlock(&sched_hotcpu_mutex);
++ if (retval)
++ return retval;
++
++ return 0;
++}
++
++/**
++ * 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 < cpumask_size())
++ return -EINVAL;
++
++ if (!alloc_cpumask_var(&mask, GFP_KERNEL))
++ return -ENOMEM;
++
++ ret = sched_getaffinity(pid, mask);
++ if (ret == 0) {
++ if (copy_to_user(user_mask_ptr, mask, cpumask_size()))
++ ret = -EFAULT;
++ else
++ ret = cpumask_size();
++ }
++ 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
++ * refilling the timeslice, resetting the deadline and scheduling away.
++ */
++SYSCALL_DEFINE0(sched_yield)
++{
++ struct task_struct *p;
++
++ grq_lock_irq();
++ p = current;
++ schedstat_inc(this_rq(), yld_count);
++ update_rq_clock(task_rq(p));
++ time_slice_expired(p);
++ 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_);
++ _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)
++{
++#ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
++ __might_sleep(__FILE__, __LINE__);
++#endif
++ /*
++ * The BKS might be reacquired before we have dropped
++ * PREEMPT_ACTIVE, which could trigger a second
++ * cond_resched() call.
++ */
++ do {
++ add_preempt_count(PREEMPT_ACTIVE);
++ schedule();
++ sub_preempt_count(PREEMPT_ACTIVE);
++ } while (need_resched());
++}
++
++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;
++
++ 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_get_cpu_var(runqueues);
++
++ delayacct_blkio_start();
++ atomic_inc(&rq->nr_iowait);
++ schedule();
++ atomic_dec(&rq->nr_iowait);
++ delayacct_blkio_end();
++}
++EXPORT_SYMBOL(io_schedule);
++
++long __sched io_schedule_timeout(long timeout)
++{
++ struct rq *rq = &__raw_get_cpu_var(runqueues);
++ long ret;
++
++ delayacct_blkio_start();
++ atomic_inc(&rq->nr_iowait);
++ ret = schedule_timeout(timeout);
++ 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_IDLE:
++ 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_IDLE:
++ 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;
++ int retval = -EINVAL;
++ struct timespec t;
++
++ if (pid < 0)
++ goto out_nounlock;
++
++ retval = -ESRCH;
++ read_lock(&tasklist_lock);
++ p = find_process_by_pid(pid);
++ if (!p)
++ goto out_unlock;
++
++ retval = security_task_getscheduler(p);
++ if (retval)
++ goto out_unlock;
++
++ t = ns_to_timespec(p->policy == SCHED_FIFO ? 0 :
++ MS_TO_NS(task_timeslice(p)));
++ read_unlock(&tasklist_lock);
++ retval = copy_to_user(interval, &t, sizeof(t)) ? -EFAULT : 0;
++out_nounlock:
++ return retval;
++out_unlock:
++ read_unlock(&tasklist_lock);
++ 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 == -1)
++ 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 __cpuinit init_idle(struct task_struct *idle, int cpu)
++{
++ struct rq *rq = cpu_rq(cpu);
++ unsigned long flags;
++
++ time_grq_lock(rq, &flags);
++ idle->timestamp = idle->last_ran = rq->clock;
++ idle->state = TASK_RUNNING;
++ /* Setting prio to illegal value shouldn't matter when never queued */
++ idle->prio = rq->rq_prio = PRIO_LIMIT;
++ rq->rq_deadline = idle->deadline;
++ rq->rq_policy = idle->policy;
++ rq->rq_time_slice = idle->rt.time_slice;
++ idle->cpus_allowed = cpumask_of_cpu(cpu);
++ set_task_cpu(idle, cpu);
++ rq->curr = rq->idle = idle;
++ idle->oncpu = 1;
++ set_cpuidle_map(cpu);
++#ifdef CONFIG_HOTPLUG_CPU
++ idle->unplugged_mask = CPU_MASK_NONE;
++#endif
++ 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
++static struct {
++ atomic_t load_balancer;
++ cpumask_var_t cpu_mask;
++ cpumask_var_t ilb_grp_nohz_mask;
++} nohz ____cacheline_aligned = {
++ .load_balancer = ATOMIC_INIT(-1),
++};
++
++int get_nohz_load_balancer(void)
++{
++ return atomic_read(&nohz.load_balancer);
++}
++
++/*
++ * This routine will try to nominate the ilb (idle load balancing)
++ * owner among the cpus whose ticks are stopped. ilb owner will do the idle
++ * load balancing on behalf of all those cpus. If all the cpus in the system
++ * go into this tickless mode, then there will be no ilb owner (as there is
++ * no need for one) and all the cpus will sleep till the next wakeup event
++ * arrives...
++ *
++ * For the ilb owner, tick is not stopped. And this tick will be used
++ * for idle load balancing. ilb owner will still be part of
++ * nohz.cpu_mask..
++ *
++ * While stopping the tick, this cpu will become the ilb owner if there
++ * is no other owner. And will be the owner till that cpu becomes busy
++ * or if all cpus in the system stop their ticks at which point
++ * there is no need for ilb owner.
++ *
++ * When the ilb owner becomes busy, it nominates another owner, during the
++ * next busy scheduler_tick()
++ */
++int select_nohz_load_balancer(int stop_tick)
++{
++ int cpu = smp_processor_id();
++
++ if (stop_tick) {
++ cpu_rq(cpu)->in_nohz_recently = 1;
++
++ if (!cpu_active(cpu)) {
++ if (atomic_read(&nohz.load_balancer) != cpu)
++ return 0;
++
++ /*
++ * If we are going offline and still the leader,
++ * give up!
++ */
++ if (atomic_cmpxchg(&nohz.load_balancer, cpu, -1) != cpu)
++ BUG();
++
++ return 0;
++ }
++
++ cpumask_set_cpu(cpu, nohz.cpu_mask);
++
++ /* time for ilb owner also to sleep */
++ if (cpumask_weight(nohz.cpu_mask) == num_online_cpus()) {
++ if (atomic_read(&nohz.load_balancer) == cpu)
++ atomic_set(&nohz.load_balancer, -1);
++ return 0;
++ }
++
++ if (atomic_read(&nohz.load_balancer) == -1) {
++ /* make me the ilb owner */
++ if (atomic_cmpxchg(&nohz.load_balancer, -1, cpu) == -1)
++ return 1;
++ } else if (atomic_read(&nohz.load_balancer) == cpu)
++ return 1;
++ } else {
++ if (!cpumask_test_cpu(cpu, nohz.cpu_mask))
++ return 0;
++
++ cpumask_clear_cpu(cpu, nohz.cpu_mask);
++
++ if (atomic_read(&nohz.load_balancer) == cpu)
++ if (atomic_cmpxchg(&nohz.load_balancer, cpu, -1) != cpu)
++ BUG();
++ }
++ return 0;
++}
++
++/*
++ * 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 serialized 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 = 0;
++ int queued = 0;
++ struct rq *rq;
++ int ret = 0;
++
++ rq = task_grq_lock(p, &flags);
++ if (!cpumask_intersects(new_mask, cpu_online_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_only(p);
++
++ cpumask_copy(&p->cpus_allowed, new_mask);
++ p->rt.nr_cpus_allowed = cpumask_weight(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;
++
++ /* Reschedule the task, schedule() will know if it can keep running */
++ if (task_running(p))
++ running = 1;
++ else
++ set_task_cpu(p, cpumask_any_and(cpu_online_mask, new_mask));
++
++out:
++ if (queued)
++ try_preempt(p);
++ task_grq_unlock(&flags);
++
++ /* This might be a flaky way of changing cpus! */
++ if (running)
++ schedule();
++ return ret;
++}
++EXPORT_SYMBOL_GPL(set_cpus_allowed_ptr);
++
++#ifdef CONFIG_HOTPLUG_CPU
++/* 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.
++ */
++ time_grq_lock(rq, &flags);
++
++ __setscheduler(idle, SCHED_FIFO, MAX_RT_PRIO - 1);
++
++ 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 */
++
++#if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_SYSCTL)
++
++static struct ctl_table sd_ctl_dir[] = {
++ {
++ .procname = "sched_domain",
++ .mode = 0555,
++ },
++ {0, },
++};
++
++static struct ctl_table sd_ctl_root[] = {
++ {
++ .ctl_name = CTL_KERN,
++ .procname = "kernel",
++ .mode = 0555,
++ .child = sd_ctl_dir,
++ },
++ {0, },
++};
++
++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_online_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_online_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(rq->cpu, rq->rd->online);
++ rq->online = 1;
++ }
++}
++
++static void set_rq_offline(struct rq *rq)
++{
++ if (rq->online) {
++ cpumask_clear_cpu(rq->cpu, rq->rd->online);
++ rq->online = 0;
++ }
++}
++
++#ifdef CONFIG_HOTPLUG_CPU
++/*
++ * This cpu is going down, so walk over the tasklist and find tasks that can
++ * only run on this cpu and remove their affinity. Store their value in
++ * unplugged_mask so it can be restored once their correct cpu is online. No
++ * need to do anything special since they'll just move on next reschedule if
++ * they're running.
++ */
++static void remove_cpu(unsigned long cpu)
++{
++ struct task_struct *p, *t;
++
++ read_lock(&tasklist_lock);
++
++ do_each_thread(t, p) {
++ cpumask_t cpus_remaining;
++
++ cpus_and(cpus_remaining, p->cpus_allowed, cpu_online_map);
++ cpu_clear(cpu, cpus_remaining);
++ if (cpus_empty(cpus_remaining)) {
++ p->unplugged_mask = p->cpus_allowed;
++ p->cpus_allowed = cpu_possible_map;
++ }
++ } while_each_thread(t, p);
++
++ read_unlock(&tasklist_lock);
++}
++
++/*
++ * This cpu is coming up so add it to the cpus_allowed.
++ */
++static void add_cpu(unsigned long cpu)
++{
++ struct task_struct *p, *t;
++
++ read_lock(&tasklist_lock);
++
++ do_each_thread(t, p) {
++ /* Have we taken all the cpus from the unplugged_mask back */
++ if (cpus_empty(p->unplugged_mask))
++ continue;
++
++ /* Was this cpu in the unplugged_mask mask */
++ if (cpu_isset(cpu, p->unplugged_mask)) {
++ cpu_set(cpu, p->cpus_allowed);
++ if (cpus_subset(p->unplugged_mask, p->cpus_allowed)) {
++ /*
++ * Have we set more than the unplugged_mask?
++ * If so, that means we have remnants set from
++ * the unplug/plug cycle and need to remove
++ * them. Then clear the unplugged_mask as we've
++ * set all the cpus back.
++ */
++ p->cpus_allowed = p->unplugged_mask;
++ cpus_clear(p->unplugged_mask);
++ }
++ }
++ } while_each_thread(t, p);
++
++ read_unlock(&tasklist_lock);
++}
++#else
++static void add_cpu(unsigned long cpu)
++{
++}
++#endif
++
++/*
++ * 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)
++{
++ int cpu = (long)hcpu;
++ unsigned long flags;
++ struct rq *rq;
++
++ switch (action) {
++
++ case CPU_UP_PREPARE:
++ case CPU_UP_PREPARE_FROZEN:
++ break;
++
++ case CPU_ONLINE:
++ case CPU_ONLINE_FROZEN:
++ /* Update our root-domain */
++ rq = cpu_rq(cpu);
++ grq_lock_irqsave(&flags);
++ if (rq->rd) {
++ BUG_ON(!cpumask_test_cpu(cpu, rq->rd->span));
++
++ set_rq_online(rq);
++ }
++ add_cpu(cpu);
++ grq_unlock_irqrestore(&flags);
++ break;
++
++#ifdef CONFIG_HOTPLUG_CPU
++ case CPU_UP_CANCELED:
++ case CPU_UP_CANCELED_FROZEN:
++ break;
++
++ case CPU_DEAD:
++ case CPU_DEAD_FROZEN:
++ cpuset_lock(); /* around calls to cpuset_cpus_allowed_lock() */
++ rq = cpu_rq(cpu);
++ /* Idle task back to normal (off runqueue, low prio) */
++ grq_lock_irq();
++ remove_cpu(cpu);
++ deactivate_task(rq->idle);
++ rq->idle->static_prio = MAX_PRIO;
++ __setscheduler(rq->idle, SCHED_NORMAL, 0);
++ rq->idle->prio = PRIO_LIMIT;
++ update_rq_clock(rq);
++ grq_unlock_irq();
++ cpuset_unlock();
++ break;
++
++ case CPU_DYING:
++ case CPU_DYING_FROZEN:
++ rq = cpu_rq(cpu);
++ 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 = 10
++};
++
++int __init migration_init(void)
++{
++ void *cpu = (void *)(long)smp_processor_id();
++ int err;
++
++ /* Start one 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);
++
++ return 0;
++}
++early_initcall(migration_init);
++#endif
++
++/*
++ * sched_domains_mutex serializes calls to arch_init_sched_domains,
++ * detach_destroy_domains and partition_sched_domains.
++ */
++static DEFINE_MUTEX(sched_domains_mutex);
++
++#ifdef CONFIG_SMP
++
++#ifdef CONFIG_SCHED_DEBUG
++
++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 (!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_IDLE |
++ SD_WAKE_AFFINE |
++ SD_WAKE_BALANCE))
++ 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;
++
++ /* Does parent contain flags not in child? */
++ /* WAKE_BALANCE is a subset of WAKE_AFFINE */
++ if (cflags & SD_WAKE_AFFINE)
++ pflags &= ~SD_WAKE_BALANCE;
++ /* 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)
++{
++ 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(rq->cpu, old_rd->online))
++ set_rq_offline(rq);
++
++ cpumask_clear_cpu(rq->cpu, 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(rq->cpu, rd->span);
++ if (cpumask_test_cpu(rq->cpu, cpu_online_mask))
++ set_rq_online(rq);
++
++ grq_unlock_irqrestore(&flags);
++
++ if (old_rd)
++ free_rootdomain(old_rd);
++}
++
++static int init_rootdomain(struct root_domain *rd, bool bootmem)
++{
++ gfp_t gfp = GFP_KERNEL;
++
++ memset(rd, 0, sizeof(*rd));
++
++ if (bootmem)
++ gfp = GFP_NOWAIT;
++
++ if (!alloc_cpumask_var(&rd->span, gfp))
++ goto out;
++ if (!alloc_cpumask_var(&rd->online, gfp))
++ goto free_span;
++ if (!alloc_cpumask_var(&rd->rto_mask, gfp))
++ goto free_online;
++
++ return 0;
++
++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, true);
++
++ 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, false) != 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;
++
++ /* 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)
++{
++ 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);
++};
++
++/*
++ * 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_group_cpus);
++
++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_group_cpus, 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);
++#endif /* CONFIG_SCHED_MC */
++
++#if defined(CONFIG_SCHED_MC) && defined(CONFIG_SCHED_SMT)
++static int
++cpu_to_core_group(int cpu, const struct cpumask *cpu_map,
++ struct sched_group **sg, struct cpumask *mask)
++{
++ int group;
++
++ cpumask_and(mask, topology_thread_cpumask(cpu), cpu_map);
++ group = cpumask_first(mask);
++ if (sg)
++ *sg = &per_cpu(sched_group_core, group).sg;
++ return group;
++}
++#elif defined(CONFIG_SCHED_MC)
++static int
++cpu_to_core_group(int cpu, const struct cpumask *cpu_map,
++ struct sched_group **sg, struct cpumask *unused)
++{
++ if (sg)
++ *sg = &per_cpu(sched_group_core, cpu).sg;
++ return cpu;
++}
++#endif
++
++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_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_inc_cpu_power(sg, sd->groups->__cpu_power);
++ }
++ sg = sg->next;
++ } while (sg != group_head);
++}
++#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 */
++
++/*
++ * Initialize 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;
++
++ WARN_ON(!sd || !sd->groups);
++
++ if (cpu != group_first_cpu(sd->groups))
++ return;
++
++ child = sd->child;
++
++ sd->groups->__cpu_power = 0;
++
++ /*
++ * For perf policy, if the groups in child domain share resources
++ * (for example cores sharing some portions of the cache hierarchy
++ * or SMT), then set this domain groups cpu_power such that each group
++ * can handle only one task, when there are other idle groups in the
++ * same sched domain.
++ */
++ if (!child || (!(sd->flags & SD_POWERSAVINGS_BALANCE) &&
++ (child->flags &
++ (SD_SHARE_CPUPOWER | SD_SHARE_PKG_RESOURCES)))) {
++ sg_inc_cpu_power(sd->groups, SCHED_LOAD_SCALE);
++ return;
++ }
++
++ /*
++ * add cpu_power of each child group to this groups cpu_power
++ */
++ group = child->groups;
++ do {
++ sg_inc_cpu_power(sd->groups, group->__cpu_power);
++ group = group->next;
++ } while (group != child->groups);
++}
++
++/*
++ * Initializers 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
++
++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_WAKE_IDLE|SD_BALANCE_NEWIDLE);
++ } else {
++ /* turn on idle balance on this domain */
++ sd->flags |= (SD_WAKE_IDLE_FAR|SD_BALANCE_NEWIDLE);
++ }
++}
++
++/*
++ * 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)
++{
++ int i, err = -ENOMEM;
++ struct root_domain *rd;
++ cpumask_var_t nodemask, this_sibling_map, this_core_map, send_covered,
++ tmpmask;
++#ifdef CONFIG_NUMA
++ cpumask_var_t domainspan, covered, notcovered;
++ struct sched_group **sched_group_nodes = NULL;
++ int sd_allnodes = 0;
++
++ if (!alloc_cpumask_var(&domainspan, GFP_KERNEL))
++ goto out;
++ if (!alloc_cpumask_var(&covered, GFP_KERNEL))
++ goto free_domainspan;
++ if (!alloc_cpumask_var(&notcovered, GFP_KERNEL))
++ goto free_covered;
++#endif
++
++ if (!alloc_cpumask_var(&nodemask, GFP_KERNEL))
++ goto free_notcovered;
++ if (!alloc_cpumask_var(&this_sibling_map, GFP_KERNEL))
++ goto free_nodemask;
++ if (!alloc_cpumask_var(&this_core_map, GFP_KERNEL))
++ goto free_this_sibling_map;
++ if (!alloc_cpumask_var(&send_covered, GFP_KERNEL))
++ goto free_this_core_map;
++ if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL))
++ goto free_send_covered;
++
++#ifdef CONFIG_NUMA
++ /*
++ * Allocate the per-node list of sched groups
++ */
++ sched_group_nodes = kcalloc(nr_node_ids, sizeof(struct sched_group *),
++ GFP_KERNEL);
++ if (!sched_group_nodes) {
++ printk(KERN_WARNING "Can not alloc sched group node list\n");
++ goto free_tmpmask;
++ }
++#endif
++
++ rd = alloc_rootdomain();
++ if (!rd) {
++ printk(KERN_WARNING "Cannot alloc root domain\n");
++ goto free_sched_groups;
++ }
++
++#ifdef CONFIG_NUMA
++ sched_group_nodes_bycpu[cpumask_first(cpu_map)] = sched_group_nodes;
++#endif
++
++ /*
++ * Set up domains for cpus specified by the cpu_map.
++ */
++ for_each_cpu(i, cpu_map) {
++ struct sched_domain *sd = NULL, *p;
++
++ cpumask_and(nodemask, cpumask_of_node(cpu_to_node(i)), cpu_map);
++
++#ifdef CONFIG_NUMA
++ if (cpumask_weight(cpu_map) >
++ SD_NODES_PER_DOMAIN*cpumask_weight(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, tmpmask);
++ p = sd;
++ sd_allnodes = 1;
++ } else
++ p = NULL;
++
++ 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 = p;
++ if (p)
++ p->child = sd;
++ cpumask_and(sched_domain_span(sd),
++ sched_domain_span(sd), cpu_map);
++#endif
++
++ p = sd;
++ sd = &per_cpu(phys_domains, i).sd;
++ SD_INIT(sd, CPU);
++ set_domain_attribute(sd, attr);
++ cpumask_copy(sched_domain_span(sd), nodemask);
++ sd->parent = p;
++ if (p)
++ p->child = sd;
++ cpu_to_phys_group(i, cpu_map, &sd->groups, tmpmask);
++
++#ifdef CONFIG_SCHED_MC
++ p = sd;
++ 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 = p;
++ p->child = sd;
++ cpu_to_core_group(i, cpu_map, &sd->groups, tmpmask);
++#endif
++
++#ifdef CONFIG_SCHED_SMT
++ p = sd;
++ sd = &per_cpu(cpu_domains, i).sd;
++ SD_INIT(sd, SIBLING);
++ set_domain_attribute(sd, attr);
++ cpumask_and(sched_domain_span(sd),
++ topology_thread_cpumask(i), cpu_map);
++ sd->parent = p;
++ p->child = sd;
++ cpu_to_cpu_group(i, cpu_map, &sd->groups, tmpmask);
++#endif
++ }
++
++#ifdef CONFIG_SCHED_SMT
++ /* Set up CPU (sibling) groups */
++ for_each_cpu(i, cpu_map) {
++ cpumask_and(this_sibling_map,
++ topology_thread_cpumask(i), cpu_map);
++ if (i != cpumask_first(this_sibling_map))
++ continue;
++
++ init_sched_build_groups(this_sibling_map, cpu_map,
++ &cpu_to_cpu_group,
++ send_covered, tmpmask);
++ }
++#endif
++
++#ifdef CONFIG_SCHED_MC
++ /* Set up multi-core groups */
++ for_each_cpu(i, cpu_map) {
++ cpumask_and(this_core_map, cpu_coregroup_mask(i), cpu_map);
++ if (i != cpumask_first(this_core_map))
++ continue;
++
++ init_sched_build_groups(this_core_map, cpu_map,
++ &cpu_to_core_group,
++ send_covered, tmpmask);
++ }
++#endif
++
++ /* Set up physical groups */
++ for (i = 0; i < nr_node_ids; i++) {
++ cpumask_and(nodemask, cpumask_of_node(i), cpu_map);
++ if (cpumask_empty(nodemask))
++ continue;
++
++ init_sched_build_groups(nodemask, cpu_map,
++ &cpu_to_phys_group,
++ send_covered, tmpmask);
++ }
++
++#ifdef CONFIG_NUMA
++ /* Set up node groups */
++ if (sd_allnodes) {
++ init_sched_build_groups(cpu_map, cpu_map,
++ &cpu_to_allnodes_group,
++ send_covered, tmpmask);
++ }
++
++ for (i = 0; i < nr_node_ids; i++) {
++ /* Set up node groups */
++ struct sched_group *sg, *prev;
++ int j;
++
++ cpumask_clear(covered);
++ cpumask_and(nodemask, cpumask_of_node(i), cpu_map);
++ if (cpumask_empty(nodemask)) {
++ sched_group_nodes[i] = NULL;
++ continue;
++ }
++
++ sched_domain_node_span(i, domainspan);
++ cpumask_and(domainspan, domainspan, cpu_map);
++
++ sg = kmalloc_node(sizeof(struct sched_group) + cpumask_size(),
++ GFP_KERNEL, i);
++ if (!sg) {
++ printk(KERN_WARNING "Can not alloc domain group for "
++ "node %d\n", i);
++ goto error;
++ }
++ sched_group_nodes[i] = sg;
++ for_each_cpu(j, nodemask) {
++ struct sched_domain *sd;
++
++ sd = &per_cpu(node_domains, j).sd;
++ sd->groups = sg;
++ }
++ sg->__cpu_power = 0;
++ cpumask_copy(sched_group_cpus(sg), nodemask);
++ sg->next = sg;
++ cpumask_or(covered, covered, nodemask);
++ prev = sg;
++
++ for (j = 0; j < nr_node_ids; j++) {
++ int n = (i + j) % nr_node_ids;
++
++ cpumask_complement(notcovered, covered);
++ cpumask_and(tmpmask, notcovered, cpu_map);
++ cpumask_and(tmpmask, tmpmask, domainspan);
++ if (cpumask_empty(tmpmask))
++ break;
++
++ cpumask_and(tmpmask, tmpmask, cpumask_of_node(n));
++ if (cpumask_empty(tmpmask))
++ continue;
++
++ sg = kmalloc_node(sizeof(struct sched_group) +
++ cpumask_size(),
++ GFP_KERNEL, i);
++ if (!sg) {
++ printk(KERN_WARNING
++ "Can not alloc domain group for node %d\n", j);
++ goto error;
++ }
++ sg->__cpu_power = 0;
++ cpumask_copy(sched_group_cpus(sg), tmpmask);
++ sg->next = prev->next;
++ cpumask_or(covered, covered, tmpmask);
++ prev->next = sg;
++ prev = sg;
++ }
++ }
++#endif
++
++ /* Calculate CPU power for physical packages and nodes */
++#ifdef CONFIG_SCHED_SMT
++ for_each_cpu(i, cpu_map) {
++ struct sched_domain *sd = &per_cpu(cpu_domains, i).sd;
++
++ init_sched_groups_power(i, sd);
++ }
++#endif
++#ifdef CONFIG_SCHED_MC
++ for_each_cpu(i, cpu_map) {
++ struct sched_domain *sd = &per_cpu(core_domains, i).sd;
++
++ init_sched_groups_power(i, sd);
++ }
++#endif
++
++ for_each_cpu(i, cpu_map) {
++ struct sched_domain *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(sched_group_nodes[i]);
++
++ if (sd_allnodes) {
++ struct sched_group *sg;
++
++ cpu_to_allnodes_group(cpumask_first(cpu_map), cpu_map, &sg,
++ tmpmask);
++ init_numa_sched_groups_power(sg);
++ }
++#endif
++
++ /* Attach the domains */
++ for_each_cpu(i, cpu_map) {
++ struct sched_domain *sd;
++#ifdef CONFIG_SCHED_SMT
++ sd = &per_cpu(cpu_domains, i).sd;
++#elif defined(CONFIG_SCHED_MC)
++ sd = &per_cpu(core_domains, i).sd;
++#else
++ sd = &per_cpu(phys_domains, i).sd;
++#endif
++ cpu_attach_domain(sd, rd, i);
++ }
++
++ err = 0;
++
++free_tmpmask:
++ free_cpumask_var(tmpmask);
++free_send_covered:
++ free_cpumask_var(send_covered);
++free_this_core_map:
++ free_cpumask_var(this_core_map);
++free_this_sibling_map:
++ free_cpumask_var(this_sibling_map);
++free_nodemask:
++ free_cpumask_var(nodemask);
++free_notcovered:
++#ifdef CONFIG_NUMA
++ free_cpumask_var(notcovered);
++free_covered:
++ free_cpumask_var(covered);
++free_domainspan:
++ free_cpumask_var(domainspan);
++out:
++#endif
++ return err;
++
++free_sched_groups:
++#ifdef CONFIG_NUMA
++ kfree(sched_group_nodes);
++#endif
++ goto free_tmpmask;
++
++#ifdef CONFIG_NUMA
++error:
++ free_sched_groups(cpu_map, tmpmask);
++ free_rootdomain(rd);
++ goto free_tmpmask;
++#endif
++}
++
++static int build_sched_domains(const struct cpumask *cpu_map)
++{
++ return __build_sched_domains(cpu_map, NULL);
++}
++
++static struct cpumask *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 virtualized 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;
++}
++
++/*
++ * 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 = kmalloc(cpumask_size(), GFP_KERNEL);
++ if (!doms_cur)
++ doms_cur = fallback_doms;
++ cpumask_andnot(doms_cur, cpu_map, cpu_isolated_map);
++ dattr_cur = NULL;
++ err = build_sched_domains(doms_cur);
++ 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'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 kmalloc'd. This routine takes
++ * ownership of it and will kfree it when done with it. If the caller
++ * failed the kmalloc 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
++ */
++/* FIXME: Change to struct cpumask *doms_new[] */
++void partition_sched_domains(int ndoms_new, struct cpumask *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_online_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)
++ kfree(doms_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,
++ char *page)
++{
++ return sprintf(page, "%u\n", sched_mc_power_savings);
++}
++static ssize_t sched_mc_power_savings_store(struct sysdev_class *class,
++ 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,
++ char *page)
++{
++ return sprintf(page, "%u\n", sched_smt_power_savings);
++}
++static ssize_t sched_smt_power_savings_store(struct sysdev_class *dev,
++ 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 */
++
++#ifndef CONFIG_CPUSETS
++/*
++ * Add online and remove offline CPUs from the scheduler domains.
++ * When cpusets are enabled they take over this function.
++ */
++static int update_sched_domains(struct notifier_block *nfb,
++ unsigned long action, void *hcpu)
++{
++ switch (action) {
++ case CPU_ONLINE:
++ case CPU_ONLINE_FROZEN:
++ case CPU_DEAD:
++ case CPU_DEAD_FROZEN:
++ partition_sched_domains(1, NULL, NULL);
++ return NOTIFY_OK;
++
++ default:
++ return NOTIFY_DONE;
++ }
++}
++#endif
++
++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;
++ }
++}
++
++void __init sched_init_smp(void)
++{
++ cpumask_var_t non_isolated_cpus;
++
++ alloc_cpumask_var(&non_isolated_cpus, 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_online_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();
++
++#ifndef CONFIG_CPUSETS
++ /* XXX: Theoretical race here - CPU may be hotplugged now */
++ hotcpu_notifier(update_sched_domains, 0);
++#endif
++
++ /* 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);
++
++ alloc_cpumask_var(&fallback_doms, GFP_KERNEL);
++
++ /*
++ * Assume that every added cpu gives us slightly less overall latency
++ * allowing us to increase the base rr_interval, but in a non linear
++ * fashion.
++ */
++ rr_interval *= 1 + ilog2(num_online_cpus());
++}
++#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;
++ int highest_cpu = 0;
++
++ prio_ratios[0] = 100;
++ for (i = 1 ; i < PRIO_RANGE ; i++)
++ prio_ratios[i] = prio_ratios[i - 1] * 11 / 10;
++
++#ifdef CONFIG_SMP
++ init_defrootdomain();
++ cpus_clear(grq.cpu_idle_map);
++#endif
++ spin_lock_init(&grq.lock);
++ for_each_possible_cpu(i) {
++ struct rq *rq;
++
++ rq = cpu_rq(i);
++ INIT_LIST_HEAD(&rq->queue);
++ rq->rq_deadline = 0;
++ rq->rq_prio = 0;
++ rq->cpu = i;
++ rq->user_pc = rq->nice_pc = rq->softirq_pc = rq->system_pc =
++ rq->iowait_pc = rq->idle_pc = 0;
++#ifdef CONFIG_SMP
++ rq->sd = NULL;
++ rq->rd = NULL;
++ rq->online = 0;
++ INIT_LIST_HEAD(&rq->migration_queue);
++ rq_attach_root(rq, &def_root_domain);
++#endif
++ atomic_set(&rq->nr_iowait, 0);
++ highest_cpu = i;
++ }
++ grq.iso_ticks = grq.nr_running = grq.nr_uninterruptible = 0;
++ for (i = 0; i < PRIO_LIMIT; i++)
++ INIT_LIST_HEAD(grq.queue + i);
++ bitmap_zero(grq.prio_bitmap, PRIO_LIMIT);
++ /* delimiter for bitsearch */
++ __set_bit(PRIO_LIMIT, grq.prio_bitmap);
++
++#ifdef CONFIG_SMP
++ nr_cpu_ids = highest_cpu + 1;
++#endif
++
++#ifdef CONFIG_PREEMPT_NOTIFIERS
++ INIT_HLIST_HEAD(&init_task.preempt_notifiers);
++#endif
++
++#ifdef CONFIG_RT_MUTEXES
++ plist_head_init(&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 */
++ alloc_cpumask_var(&nohz_cpu_mask, GFP_NOWAIT);
++#ifdef CONFIG_SMP
++#ifdef CONFIG_NO_HZ
++ alloc_cpumask_var(&nohz.cpu_mask, GFP_NOWAIT);
++ alloc_cpumask_var(&nohz.ilb_grp_nohz_mask, GFP_NOWAIT);
++#endif
++ alloc_cpumask_var(&cpu_isolated_map, GFP_NOWAIT);
++#endif /* SMP */
++ perf_counter_init();
++}
++
++#ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
++void __might_sleep(char *file, int line)
++{
++#ifdef in_atomic
++ static unsigned long prev_jiffy; /* ratelimiting */
++
++ if ((in_atomic() || irqs_disabled()) &&
++ system_state == SYSTEM_RUNNING && !oops_in_progress) {
++ 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("in_atomic():%d, irqs_disabled():%d\n",
++ in_atomic(), irqs_disabled());
++ 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;
++
++ spin_lock_irqsave(&p->pi_lock, flags);
++ rq = __task_grq_lock(p);
++ update_rq_clock(rq);
++
++ queued = task_queued_only(p);
++ if (queued)
++ dequeue_task(p);
++ __setscheduler(p, SCHED_NORMAL, 0);
++ if (task_running(p))
++ resched_task(p);
++ if (queued) {
++ enqueue_task(p);
++ try_preempt(p);
++ }
++
++ __task_grq_unlock();
++ spin_unlock_irqrestore(&p->pi_lock, flags);
++ } while_each_thread(g, p);
++
++ read_unlock_irq(&tasklist_lock);
++}
++#endif /* CONFIG_MAGIC_SYSRQ */
++
++#ifdef CONFIG_IA64
++/*
++ * These functions are only useful for the IA64 MCA handling.
++ *
++ * 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);
++}
++
++/**
++ * 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 synchronized, 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
++cputime_t task_utime(struct task_struct *p)
++{
++ return p->utime;
++}
++
++cputime_t task_stime(struct task_struct *p)
++{
++ return p->stime;
++}
++#else
++cputime_t task_utime(struct task_struct *p)
++{
++ clock_t utime = cputime_to_clock_t(p->utime),
++ total = utime + cputime_to_clock_t(p->stime);
++ u64 temp;
++
++ temp = (u64)nsec_to_clock_t(p->se.sum_exec_runtime);
++
++ if (total) {
++ temp *= utime;
++ do_div(temp, total);
++ }
++ utime = (clock_t)temp;
++
++ p->prev_utime = max(p->prev_utime, clock_t_to_cputime(utime));
++ return p->prev_utime;
++}
++
++cputime_t task_stime(struct task_struct *p)
++{
++ clock_t stime;
++
++ stime = nsec_to_clock_t(p->se.sum_exec_runtime) -
++ cputime_to_clock_t(task_utime(p));
++
++ if (stime >= 0)
++ p->prev_stime = max(p->prev_stime, clock_t_to_cputime(stime));
++
++ return p->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
+--- a/kernel/sysctl.c
++++ b/kernel/sysctl.c
+@@ -86,6 +86,8 @@ extern int percpu_pagelist_fraction;
+ extern int compat_log;
+ extern int latencytop_enabled;
+ extern int sysctl_nr_open_min, sysctl_nr_open_max;
++extern int rr_interval;
++extern int sched_iso_cpu;
+ #ifndef CONFIG_MMU
+ extern int sysctl_nr_trim_pages;
+ #endif
+@@ -103,7 +105,8 @@ static int zero;
+ 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 __read_mostly one_hundred = 100;
++static int __maybe_unused __read_mostly five_thousand = 5000;
+
+ /* this is needed for the proc_doulongvec_minmax of vm_dirty_bytes */
+ static unsigned long dirty_bytes_min = 2 * PAGE_SIZE;
+@@ -238,7 +241,7 @@ static struct ctl_table root_table[] = {
+ { .ctl_name = 0 }
+ };
+
+-#ifdef CONFIG_SCHED_DEBUG
++#if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_SCHED_CFS)
+ 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 */
+@@ -246,7 +249,7 @@ static int max_wakeup_granularity_ns = N
+ #endif
+
+ static struct ctl_table kern_table[] = {
+-#ifdef CONFIG_SCHED_DEBUG
++#if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_SCHED_CFS)
+ {
+ .ctl_name = CTL_UNNUMBERED,
+ .procname = "sched_min_granularity_ns",
+@@ -342,6 +345,7 @@ static struct ctl_table kern_table[] = {
+ .extra2 = &one,
+ },
+ #endif
++#ifdef CONFIG_SCHED_CFS
+ {
+ .ctl_name = CTL_UNNUMBERED,
+ .procname = "sched_rt_period_us",
+@@ -366,6 +370,7 @@ static struct ctl_table kern_table[] = {
+ .mode = 0644,
+ .proc_handler = &proc_dointvec,
+ },
++#endif
+ #ifdef CONFIG_PROVE_LOCKING
+ {
+ .ctl_name = CTL_UNNUMBERED,
+@@ -798,6 +803,30 @@ static struct ctl_table kern_table[] = {
+ .proc_handler = &proc_dointvec,
+ },
+ #endif
++#ifdef CONFIG_SCHED_BFS
++ {
++ .ctl_name = CTL_UNNUMBERED,
++ .procname = "rr_interval",
++ .data = &rr_interval,
++ .maxlen = sizeof (int),
++ .mode = 0644,
++ .proc_handler = &proc_dointvec_minmax,
++ .strategy = &sysctl_intvec,
++ .extra1 = &one,
++ .extra2 = &five_thousand,
++ },
++ {
++ .ctl_name = CTL_UNNUMBERED,
++ .procname = "iso_cpu",
++ .data = &sched_iso_cpu,
++ .maxlen = sizeof (int),
++ .mode = 0644,
++ .proc_handler = &proc_dointvec_minmax,
++ .strategy = &sysctl_intvec,
++ .extra1 = &zero,
++ .extra2 = &one_hundred,
++ },
++#endif
+ #if defined(CONFIG_S390) && defined(CONFIG_SMP)
+ {
+ .ctl_name = KERN_SPIN_RETRY,
+--- a/kernel/workqueue.c
++++ b/kernel/workqueue.c
+@@ -317,7 +317,9 @@ static int worker_thread(void *__cwq)
+ if (cwq->wq->freezeable)
+ set_freezable();
+
++#ifdef CONFIG_SCHED_CFS
+ set_user_nice(current, -5);
++#endif
+
+ for (;;) {
+ prepare_to_wait(&cwq->more_work, &wait, TASK_INTERRUPTIBLE);