diff options
| -rw-r--r-- | target/linux/generic-2.6/config-2.6.30 | 2 | ||||
| -rw-r--r-- | target/linux/generic-2.6/patches-2.6.30/270-sched_bfs.patch | 6411 |
2 files changed, 6413 insertions, 0 deletions
diff --git a/target/linux/generic-2.6/config-2.6.30 b/target/linux/generic-2.6/config-2.6.30 index cf3d0b5e39..9202ffe993 100644 --- a/target/linux/generic-2.6/config-2.6.30 +++ b/target/linux/generic-2.6/config-2.6.30 @@ -1618,6 +1618,8 @@ CONFIG_RWSEM_GENERIC_SPINLOCK=y # CONFIG_SATA_VITESSE is not set # CONFIG_SC92031 is not set # CONFIG_SCC is not set +# CONFIG_SCHED_BFS is not set +CONFIG_SCHED_CFS=y # CONFIG_SCHED_TRACER is not set # CONFIG_SCSI_3W_9XXX is not set # CONFIG_SCSI_7000FASST is not set diff --git a/target/linux/generic-2.6/patches-2.6.30/270-sched_bfs.patch b/target/linux/generic-2.6/patches-2.6.30/270-sched_bfs.patch new file mode 100644 index 0000000000..f521b3239c --- /dev/null +++ b/target/linux/generic-2.6/patches-2.6.30/270-sched_bfs.patch @@ -0,0 +1,6411 @@ +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 ] +@@ -48,6 +49,7 @@ 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 +@@ -170,6 +172,16 @@ 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 +@@ -322,6 +334,19 @@ 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 +@@ -119,9 +119,10 @@ 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 { +@@ -1042,10 +1045,13 @@ 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; + +@@ -1096,6 +1102,7 @@ struct sched_entity { + /* rq "owned" by this entity/group: */ + struct cfs_rq *my_q; + #endif ++#endif + }; + + struct sched_rt_entity { +@@ -1123,17 +1130,19 @@ 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: */ +@@ -1156,6 +1165,9 @@ 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; +@@ -1446,11 +1458,19 @@ 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) +@@ -1734,7 +1754,7 @@ 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 +@@ -435,9 +435,22 @@ 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 +@@ -488,6 +501,7 @@ 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 $(CONFIG_SCHED_CFS),sched.o,sched_bfs.o) fork.o exec_domain.o panic.o printk.o \ + cpu.o exit.o itimer.o time.o softirq.o resource.o \ + sysctl.o capability.o ptrace.o timer.o user.o \ + signal.o sys.o kmod.o workqueue.o pid.o \ +@@ -103,6 +103,7 @@ ifneq ($(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 +@@ -15,7 +15,11 @@ + #include <linux/mutex.h> + #include <trace/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 +1,6059 @@ ++/* ++ * 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(¬ifier->link, ¤t->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(¬ifier->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(); ++} ++ ++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(¬covered, 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 +@@ -83,6 +83,8 @@ 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 +@@ -100,7 +102,8 @@ 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; +@@ -234,7 +237,7 @@ 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 */ +@@ -242,7 +245,7 @@ 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", +@@ -327,6 +330,7 @@ static struct ctl_table kern_table[] = { + .proc_handler = &proc_dointvec, + }, + #endif ++#ifdef CONFIG_SCHED_CFS + { + .ctl_name = CTL_UNNUMBERED, + .procname = "sched_rt_period_us", +@@ -351,6 +355,7 @@ static struct ctl_table kern_table[] = { + .mode = 0644, + .proc_handler = &proc_dointvec, + }, ++#endif + #ifdef CONFIG_PROVE_LOCKING + { + .ctl_name = CTL_UNNUMBERED, +@@ -756,6 +761,30 @@ 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 +@@ -320,7 +320,9 @@ 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); +--- /dev/null ++++ b/include/linux/perf_counter.h +@@ -0,0 +1,2 @@ ++#define perf_counter_init() do {} while(0) ++#define perf_counter_task_sched_in(...) do {} while(0) +--- /dev/null ++++ b/include/trace/events/sched.h +@@ -0,0 +1 @@ ++#include <trace/sched.h> |