* 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
*/
#include <linux/mm.h>
#include <linux/reciprocal_div.h>
#include <linux/unistd.h>
#include <linux/pagemap.h>
+#include <linux/hrtimer.h>
#include <asm/tlb.h>
#include <asm/irq_regs.h>
struct cfs_rq;
+static LIST_HEAD(task_groups);
+
/* task group related information */
struct task_group {
#ifdef CONFIG_FAIR_CGROUP_SCHED
/* runqueue "owned" by this group on each cpu */
struct cfs_rq **cfs_rq;
+ struct sched_rt_entity **rt_se;
+ struct rt_rq **rt_rq;
+
+ unsigned int rt_ratio;
+
/*
* shares assigned to a task group governs how much of cpu bandwidth
* is allocated to the group. The more shares a group has, the more is
*
* Bw(A) = 1000/(1000+2000+3000) * 100 = 16.66%
* Bw(B) = 2000/(1000+2000+3000) * 100 = 33.33%
- * Bw(C) = 3000/(1000+2000+3000) * 100 = 50%
+ * Bw(C) = 3000/(1000+2000+3000) * 100 = 50%
*
* The weight assigned to a task group's schedulable entities on every
* cpu (task_group.se[a_cpu]->load.weight) is derived from the task
* tg_A->se[0]->load.weight = tg_A->se[1]->load.weight = 1000;
*
* Note: It's not necessary that each of a task's group schedulable
- * entity have the same weight on all CPUs. If the group
- * has 2 of its tasks on CPU0 and 1 task on CPU1, then a
- * better distribution of weight could be:
+ * entity have the same weight on all CPUs. If the group
+ * has 2 of its tasks on CPU0 and 1 task on CPU1, then a
+ * better distribution of weight could be:
*
* tg_A->se[0]->load.weight = 2/3 * 2000 = 1333
* tg_A->se[1]->load.weight = 1/2 * 2000 = 667
unsigned long shares;
struct rcu_head rcu;
+ struct list_head list;
};
/* Default task group's sched entity on each cpu */
/* Default task group's cfs_rq on each cpu */
static DEFINE_PER_CPU(struct cfs_rq, init_cfs_rq) ____cacheline_aligned_in_smp;
+static DEFINE_PER_CPU(struct sched_rt_entity, init_sched_rt_entity);
+static DEFINE_PER_CPU(struct rt_rq, init_rt_rq) ____cacheline_aligned_in_smp;
+
static struct sched_entity *init_sched_entity_p[NR_CPUS];
static struct cfs_rq *init_cfs_rq_p[NR_CPUS];
+static struct sched_rt_entity *init_sched_rt_entity_p[NR_CPUS];
+static struct rt_rq *init_rt_rq_p[NR_CPUS];
+
/* task_group_mutex serializes add/remove of task groups and also changes to
* a task group's cpu shares.
*/
* Every task in system belong to this group at bootup.
*/
struct task_group init_task_group = {
- .se = init_sched_entity_p,
+ .se = init_sched_entity_p,
.cfs_rq = init_cfs_rq_p,
+
+ .rt_se = init_sched_rt_entity_p,
+ .rt_rq = init_rt_rq_p,
};
#ifdef CONFIG_FAIR_USER_SCHED
-# define INIT_TASK_GROUP_LOAD 2*NICE_0_LOAD
+# define INIT_TASK_GROUP_LOAD (2*NICE_0_LOAD)
#else
# define INIT_TASK_GROUP_LOAD NICE_0_LOAD
#endif
-#define MIN_GROUP_SHARES 2
+#define MIN_GROUP_SHARES 2
static int init_task_group_load = INIT_TASK_GROUP_LOAD;
}
/* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */
-static inline void set_task_cfs_rq(struct task_struct *p, unsigned int cpu)
+static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
{
p->se.cfs_rq = task_group(p)->cfs_rq[cpu];
p->se.parent = task_group(p)->se[cpu];
+
+ p->rt.rt_rq = task_group(p)->rt_rq[cpu];
+ p->rt.parent = task_group(p)->rt_se[cpu];
}
static inline void lock_task_group_list(void)
#else
-static inline void set_task_cfs_rq(struct task_struct *p, unsigned int cpu) { }
+static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
static inline void lock_task_group_list(void) { }
static inline void unlock_task_group_list(void) { }
static inline void lock_doms_cur(void) { }
/* Real-Time classes' related field in a runqueue: */
struct rt_rq {
struct rt_prio_array active;
- int rt_load_balance_idx;
- struct list_head *rt_load_balance_head, *rt_load_balance_curr;
unsigned long rt_nr_running;
+#if defined CONFIG_SMP || defined CONFIG_FAIR_GROUP_SCHED
+ int highest_prio; /* highest queued rt task prio */
+#endif
+#ifdef CONFIG_SMP
unsigned long rt_nr_migratory;
- /* highest queued rt task prio */
- int highest_prio;
int overloaded;
+#endif
+ int rt_throttled;
+ u64 rt_time;
+
+#ifdef CONFIG_FAIR_GROUP_SCHED
+ struct rq *rq;
+ struct list_head leaf_rt_rq_list;
+ struct task_group *tg;
+ struct sched_rt_entity *rt_se;
+#endif
};
#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
+ * 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.
*
- * By default the system creates a single root-domain with all cpus as
- * members (mimicking the global state we have today).
*/
struct root_domain {
atomic_t refcount;
cpumask_t span;
cpumask_t online;
- /*
+ /*
* The "RT overload" flag: it gets set if a CPU has more than
* one runnable RT task.
*/
cpumask_t rto_mask;
- atomic_t rto_count;
+ atomic_t rto_count;
};
+/*
+ * 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
u64 nr_switches;
struct cfs_rq cfs;
+ struct rt_rq rt;
+ u64 rt_period_expire;
+ int rt_throttled;
+
#ifdef CONFIG_FAIR_GROUP_SCHED
/* list of leaf cfs_rq on this cpu: */
struct list_head leaf_cfs_rq_list;
+ struct list_head leaf_rt_rq_list;
#endif
- struct rt_rq rt;
/*
* This is part of a global counter where only the total sum
u64 clock, prev_clock_raw;
s64 clock_max_delta;
- unsigned int clock_warps, clock_overflows;
+ unsigned int clock_warps, clock_overflows, clock_underflows;
u64 idle_clock;
unsigned int clock_deep_idle_events;
u64 tick_timestamp;
atomic_t nr_iowait;
#ifdef CONFIG_SMP
- struct root_domain *rd;
+ struct root_domain *rd;
struct sched_domain *sd;
/* For active balancing */
struct list_head migration_queue;
#endif
+#ifdef CONFIG_SCHED_HRTICK
+ unsigned long hrtick_flags;
+ ktime_t hrtick_expire;
+ struct hrtimer hrtick_timer;
+#endif
+
#ifdef CONFIG_SCHEDSTATS
/* latency stats */
struct sched_info rq_sched_info;
#define task_rq(p) cpu_rq(task_cpu(p))
#define cpu_curr(cpu) (cpu_rq(cpu)->curr)
+unsigned long rt_needs_cpu(int cpu)
+{
+ struct rq *rq = cpu_rq(cpu);
+ u64 delta;
+
+ if (!rq->rt_throttled)
+ return 0;
+
+ if (rq->clock > rq->rt_period_expire)
+ return 1;
+
+ delta = rq->rt_period_expire - rq->clock;
+ do_div(delta, NSEC_PER_SEC / HZ);
+
+ return (unsigned long)delta;
+}
+
/*
* Tunables that become constants when CONFIG_SCHED_DEBUG is off:
*/
SCHED_FEAT_START_DEBIT = 4,
SCHED_FEAT_TREE_AVG = 8,
SCHED_FEAT_APPROX_AVG = 16,
+ SCHED_FEAT_HRTICK = 32,
+ SCHED_FEAT_DOUBLE_TICK = 64,
};
const_debug unsigned int sysctl_sched_features =
SCHED_FEAT_WAKEUP_PREEMPT * 1 |
SCHED_FEAT_START_DEBIT * 1 |
SCHED_FEAT_TREE_AVG * 0 |
- SCHED_FEAT_APPROX_AVG * 0;
+ SCHED_FEAT_APPROX_AVG * 0 |
+ SCHED_FEAT_HRTICK * 1 |
+ SCHED_FEAT_DOUBLE_TICK * 0;
#define sched_feat(x) (sysctl_sched_features & SCHED_FEAT_##x)
*/
const_debug unsigned int sysctl_sched_nr_migrate = 32;
+/*
+ * period over which we measure -rt task cpu usage in ms.
+ * default: 1s
+ */
+const_debug unsigned int sysctl_sched_rt_period = 1000;
+
+#define SCHED_RT_FRAC_SHIFT 16
+#define SCHED_RT_FRAC (1UL << SCHED_RT_FRAC_SHIFT)
+
+/*
+ * ratio of time -rt tasks may consume.
+ * default: 95%
+ */
+const_debug unsigned int sysctl_sched_rt_ratio = 62259;
+
/*
* For kernel-internal use: high-speed (but slightly incorrect) per-cpu
* clock constructed from sched_clock():
struct rq *rq = cpu_rq(smp_processor_id());
u64 now = sched_clock();
- touch_softlockup_watchdog();
rq->idle_clock += delta_ns;
/*
* Override the previous timestamp and ignore all
rq->prev_clock_raw = now;
rq->clock += delta_ns;
spin_unlock(&rq->lock);
+ touch_softlockup_watchdog();
}
EXPORT_SYMBOL_GPL(sched_clock_idle_wakeup_event);
+static void __resched_task(struct task_struct *p, int tif_bit);
+
+static inline void resched_task(struct task_struct *p)
+{
+ __resched_task(p, TIF_NEED_RESCHED);
+}
+
+#ifdef CONFIG_SCHED_HRTICK
+/*
+ * Use HR-timers to deliver accurate preemption points.
+ *
+ * Its all a bit involved since we cannot program an hrt while holding the
+ * rq->lock. So what we do is store a state in in rq->hrtick_* and ask for a
+ * reschedule event.
+ *
+ * When we get rescheduled we reprogram the hrtick_timer outside of the
+ * rq->lock.
+ */
+static inline void resched_hrt(struct task_struct *p)
+{
+ __resched_task(p, TIF_HRTICK_RESCHED);
+}
+
+static inline void resched_rq(struct rq *rq)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&rq->lock, flags);
+ resched_task(rq->curr);
+ spin_unlock_irqrestore(&rq->lock, flags);
+}
+
+enum {
+ HRTICK_SET, /* re-programm hrtick_timer */
+ HRTICK_RESET, /* not a new slice */
+};
+
+/*
+ * Use hrtick when:
+ * - enabled by features
+ * - hrtimer is actually high res
+ */
+static inline int hrtick_enabled(struct rq *rq)
+{
+ if (!sched_feat(HRTICK))
+ return 0;
+ return hrtimer_is_hres_active(&rq->hrtick_timer);
+}
+
+/*
+ * Called to set the hrtick timer state.
+ *
+ * called with rq->lock held and irqs disabled
+ */
+static void hrtick_start(struct rq *rq, u64 delay, int reset)
+{
+ assert_spin_locked(&rq->lock);
+
+ /*
+ * preempt at: now + delay
+ */
+ rq->hrtick_expire =
+ ktime_add_ns(rq->hrtick_timer.base->get_time(), delay);
+ /*
+ * indicate we need to program the timer
+ */
+ __set_bit(HRTICK_SET, &rq->hrtick_flags);
+ if (reset)
+ __set_bit(HRTICK_RESET, &rq->hrtick_flags);
+
+ /*
+ * New slices are called from the schedule path and don't need a
+ * forced reschedule.
+ */
+ if (reset)
+ resched_hrt(rq->curr);
+}
+
+static void hrtick_clear(struct rq *rq)
+{
+ if (hrtimer_active(&rq->hrtick_timer))
+ hrtimer_cancel(&rq->hrtick_timer);
+}
+
+/*
+ * Update the timer from the possible pending state.
+ */
+static void hrtick_set(struct rq *rq)
+{
+ ktime_t time;
+ int set, reset;
+ unsigned long flags;
+
+ WARN_ON_ONCE(cpu_of(rq) != smp_processor_id());
+
+ spin_lock_irqsave(&rq->lock, flags);
+ set = __test_and_clear_bit(HRTICK_SET, &rq->hrtick_flags);
+ reset = __test_and_clear_bit(HRTICK_RESET, &rq->hrtick_flags);
+ time = rq->hrtick_expire;
+ clear_thread_flag(TIF_HRTICK_RESCHED);
+ spin_unlock_irqrestore(&rq->lock, flags);
+
+ if (set) {
+ hrtimer_start(&rq->hrtick_timer, time, HRTIMER_MODE_ABS);
+ if (reset && !hrtimer_active(&rq->hrtick_timer))
+ resched_rq(rq);
+ } else
+ hrtick_clear(rq);
+}
+
+/*
+ * High-resolution timer tick.
+ * Runs from hardirq context with interrupts disabled.
+ */
+static enum hrtimer_restart hrtick(struct hrtimer *timer)
+{
+ struct rq *rq = container_of(timer, struct rq, hrtick_timer);
+
+ WARN_ON_ONCE(cpu_of(rq) != smp_processor_id());
+
+ spin_lock(&rq->lock);
+ __update_rq_clock(rq);
+ rq->curr->sched_class->task_tick(rq, rq->curr, 1);
+ spin_unlock(&rq->lock);
+
+ return HRTIMER_NORESTART;
+}
+
+static inline void init_rq_hrtick(struct rq *rq)
+{
+ rq->hrtick_flags = 0;
+ hrtimer_init(&rq->hrtick_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+ rq->hrtick_timer.function = hrtick;
+ rq->hrtick_timer.cb_mode = HRTIMER_CB_IRQSAFE_NO_SOFTIRQ;
+}
+
+void hrtick_resched(void)
+{
+ struct rq *rq;
+ unsigned long flags;
+
+ if (!test_thread_flag(TIF_HRTICK_RESCHED))
+ return;
+
+ local_irq_save(flags);
+ rq = cpu_rq(smp_processor_id());
+ hrtick_set(rq);
+ local_irq_restore(flags);
+}
+#else
+static inline void hrtick_clear(struct rq *rq)
+{
+}
+
+static inline void hrtick_set(struct rq *rq)
+{
+}
+
+static inline void init_rq_hrtick(struct rq *rq)
+{
+}
+
+void hrtick_resched(void)
+{
+}
+#endif
+
/*
* resched_task - mark a task 'to be rescheduled now'.
*
#define tsk_is_polling(t) test_tsk_thread_flag(t, TIF_POLLING_NRFLAG)
#endif
-static void resched_task(struct task_struct *p)
+static void __resched_task(struct task_struct *p, int tif_bit)
{
int cpu;
assert_spin_locked(&task_rq(p)->lock);
- if (unlikely(test_tsk_thread_flag(p, TIF_NEED_RESCHED)))
+ if (unlikely(test_tsk_thread_flag(p, tif_bit)))
return;
- set_tsk_thread_flag(p, TIF_NEED_RESCHED);
+ set_tsk_thread_flag(p, tif_bit);
cpu = task_cpu(p);
if (cpu == smp_processor_id())
spin_unlock_irqrestore(&rq->lock, flags);
}
#else
-static inline void resched_task(struct task_struct *p)
+static void __resched_task(struct task_struct *p, int tif_bit)
{
assert_spin_locked(&task_rq(p)->lock);
- set_tsk_need_resched(p);
+ set_tsk_thread_flag(p, tif_bit);
}
#endif
#define sched_class_highest (&rt_sched_class)
-static void inc_nr_running(struct task_struct *p, struct rq *rq)
+static void inc_nr_running(struct rq *rq)
{
rq->nr_running++;
}
-static void dec_nr_running(struct task_struct *p, struct rq *rq)
+static void dec_nr_running(struct rq *rq)
{
rq->nr_running--;
}
*/
static void activate_task(struct rq *rq, struct task_struct *p, int wakeup)
{
- if (p->state == TASK_UNINTERRUPTIBLE)
+ if (task_contributes_to_load(p))
rq->nr_uninterruptible--;
enqueue_task(rq, p, wakeup);
- inc_nr_running(p, rq);
+ inc_nr_running(rq);
}
/*
*/
static void deactivate_task(struct rq *rq, struct task_struct *p, int sleep)
{
- if (p->state == TASK_UNINTERRUPTIBLE)
+ if (task_contributes_to_load(p))
rq->nr_uninterruptible++;
dequeue_task(rq, p, sleep);
- dec_nr_running(p, rq);
+ dec_nr_running(rq);
}
/**
static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
{
- set_task_cfs_rq(p, cpu);
+ set_task_rq(p, cpu);
#ifdef CONFIG_SMP
/*
* After ->cpu is set up to a new value, task_rq_lock(p, ...) can be
#endif
}
+static inline void check_class_changed(struct rq *rq, struct task_struct *p,
+ const struct sched_class *prev_class,
+ int oldprio, int running)
+{
+ if (prev_class != p->sched_class) {
+ if (prev_class->switched_from)
+ prev_class->switched_from(rq, p, running);
+ p->sched_class->switched_to(rq, p, running);
+ } else
+ p->sched_class->prio_changed(rq, p, oldprio, running);
+}
+
#ifdef CONFIG_SMP
/*
unsigned long flags;
long old_state;
struct rq *rq;
-#ifdef CONFIG_SMP
- int new_cpu;
-#endif
rq = task_rq_lock(p, &flags);
old_state = p->state;
if (unlikely(task_running(rq, p)))
goto out_activate;
- new_cpu = p->sched_class->select_task_rq(p, sync);
- if (new_cpu != cpu) {
- set_task_cpu(p, new_cpu);
+ cpu = p->sched_class->select_task_rq(p, sync);
+ if (cpu != orig_cpu) {
+ set_task_cpu(p, cpu);
task_rq_unlock(rq, &flags);
/* might preempt at this point */
rq = task_rq_lock(p, &flags);
}
}
}
-
#endif
-
out_activate:
#endif /* CONFIG_SMP */
schedstat_inc(p, se.nr_wakeups);
out_running:
p->state = TASK_RUNNING;
- wakeup_balance_rt(rq, p);
+#ifdef CONFIG_SMP
+ if (p->sched_class->task_wake_up)
+ p->sched_class->task_wake_up(rq, p);
+#endif
out:
task_rq_unlock(rq, &flags);
return success;
}
-int fastcall wake_up_process(struct task_struct *p)
+int wake_up_process(struct task_struct *p)
{
- return try_to_wake_up(p, TASK_STOPPED | TASK_TRACED |
- TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE, 0);
+ return try_to_wake_up(p, TASK_ALL, 0);
}
EXPORT_SYMBOL(wake_up_process);
-int fastcall wake_up_state(struct task_struct *p, unsigned int state)
+int wake_up_state(struct task_struct *p, unsigned int state)
{
return try_to_wake_up(p, state, 0);
}
p->se.wait_max = 0;
#endif
- INIT_LIST_HEAD(&p->run_list);
+ INIT_LIST_HEAD(&p->rt.run_list);
p->se.on_rq = 0;
#ifdef CONFIG_PREEMPT_NOTIFIERS
* that must be done for every newly created context, then puts the task
* on the runqueue and wakes it.
*/
-void fastcall wake_up_new_task(struct task_struct *p, unsigned long clone_flags)
+void wake_up_new_task(struct task_struct *p, unsigned long clone_flags)
{
unsigned long flags;
struct rq *rq;
* management (if any):
*/
p->sched_class->task_new(rq, p);
- inc_nr_running(p, rq);
+ inc_nr_running(rq);
}
check_preempt_curr(rq, p);
- wakeup_balance_rt(rq, p);
+#ifdef CONFIG_SMP
+ if (p->sched_class->task_wake_up)
+ p->sched_class->task_wake_up(rq, p);
+#endif
task_rq_unlock(rq, &flags);
}
prev_state = prev->state;
finish_arch_switch(prev);
finish_lock_switch(rq, prev);
- schedule_tail_balance_rt(rq);
+#ifdef CONFIG_SMP
+ if (current->sched_class->post_schedule)
+ current->sched_class->post_schedule(rq);
+#endif
fire_sched_in_preempt_notifiers(current);
if (mm)
/*
* Let rq->clock advance by at least TICK_NSEC:
*/
- if (unlikely(rq->clock < next_tick))
+ if (unlikely(rq->clock < next_tick)) {
rq->clock = next_tick;
+ rq->clock_underflows++;
+ }
rq->tick_timestamp = rq->clock;
update_cpu_load(rq);
- if (curr != rq->idle) /* FIXME: needed? */
- curr->sched_class->task_tick(rq, curr);
+ curr->sched_class->task_tick(rq, curr, 0);
+ update_sched_rt_period(rq);
spin_unlock(&rq->lock);
#ifdef CONFIG_SMP
#if defined(CONFIG_PREEMPT) && defined(CONFIG_DEBUG_PREEMPT)
-void fastcall add_preempt_count(int val)
+void add_preempt_count(int val)
{
/*
* Underflow?
}
EXPORT_SYMBOL(add_preempt_count);
-void fastcall sub_preempt_count(int val)
+void sub_preempt_count(int val)
{
/*
* Underflow?
schedule_debug(prev);
+ hrtick_clear(rq);
+
/*
* Do the rq-clock update outside the rq lock:
*/
switch_count = &prev->nvcsw;
}
- schedule_balance_rt(rq, prev);
+#ifdef CONFIG_SMP
+ if (prev->sched_class->pre_schedule)
+ prev->sched_class->pre_schedule(rq, prev);
+#endif
if (unlikely(!rq->nr_running))
idle_balance(cpu, rq);
++*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
spin_unlock_irq(&rq->lock);
- if (unlikely(reacquire_kernel_lock(current) < 0)) {
- cpu = smp_processor_id();
- rq = cpu_rq(cpu);
+ hrtick_set(rq);
+
+ if (unlikely(reacquire_kernel_lock(current) < 0))
goto need_resched_nonpreemptible;
- }
+
preempt_enable_no_resched();
if (unlikely(test_thread_flag(TIF_NEED_RESCHED)))
goto need_resched;
asmlinkage void __sched preempt_schedule(void)
{
struct thread_info *ti = current_thread_info();
-#ifdef CONFIG_PREEMPT_BKL
struct task_struct *task = current;
int saved_lock_depth;
-#endif
+
/*
* If there is a non-zero preempt_count or interrupts are disabled,
* we do not want to preempt the current task. Just return..
* clear ->lock_depth so that schedule() doesnt
* auto-release the semaphore:
*/
-#ifdef CONFIG_PREEMPT_BKL
saved_lock_depth = task->lock_depth;
task->lock_depth = -1;
-#endif
schedule();
-#ifdef CONFIG_PREEMPT_BKL
task->lock_depth = saved_lock_depth;
-#endif
sub_preempt_count(PREEMPT_ACTIVE);
/*
asmlinkage void __sched preempt_schedule_irq(void)
{
struct thread_info *ti = current_thread_info();
-#ifdef CONFIG_PREEMPT_BKL
struct task_struct *task = current;
int saved_lock_depth;
-#endif
+
/* Catch callers which need to be fixed */
BUG_ON(ti->preempt_count || !irqs_disabled());
* clear ->lock_depth so that schedule() doesnt
* auto-release the semaphore:
*/
-#ifdef CONFIG_PREEMPT_BKL
saved_lock_depth = task->lock_depth;
task->lock_depth = -1;
-#endif
local_irq_enable();
schedule();
local_irq_disable();
-#ifdef CONFIG_PREEMPT_BKL
task->lock_depth = saved_lock_depth;
-#endif
sub_preempt_count(PREEMPT_ACTIVE);
/*
* @nr_exclusive: how many wake-one or wake-many threads to wake up
* @key: is directly passed to the wakeup function
*/
-void fastcall __wake_up(wait_queue_head_t *q, unsigned int mode,
+void __wake_up(wait_queue_head_t *q, unsigned int mode,
int nr_exclusive, void *key)
{
unsigned long flags;
/*
* Same as __wake_up but called with the spinlock in wait_queue_head_t held.
*/
-void fastcall __wake_up_locked(wait_queue_head_t *q, unsigned int mode)
+void __wake_up_locked(wait_queue_head_t *q, unsigned int mode)
{
__wake_up_common(q, mode, 1, 0, NULL);
}
*
* On UP it can prevent extra preemption.
*/
-void fastcall
+void
__wake_up_sync(wait_queue_head_t *q, unsigned int mode, int nr_exclusive)
{
unsigned long flags;
spin_lock_irqsave(&x->wait.lock, flags);
x->done++;
- __wake_up_common(&x->wait, TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE,
- 1, 0, NULL);
+ __wake_up_common(&x->wait, TASK_NORMAL, 1, 0, NULL);
spin_unlock_irqrestore(&x->wait.lock, flags);
}
EXPORT_SYMBOL(complete);
spin_lock_irqsave(&x->wait.lock, flags);
x->done += UINT_MAX/2;
- __wake_up_common(&x->wait, TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE,
- 0, 0, NULL);
+ __wake_up_common(&x->wait, TASK_NORMAL, 0, 0, NULL);
spin_unlock_irqrestore(&x->wait.lock, flags);
}
EXPORT_SYMBOL(complete_all);
wait.flags |= WQ_FLAG_EXCLUSIVE;
__add_wait_queue_tail(&x->wait, &wait);
do {
- if (state == TASK_INTERRUPTIBLE &&
- signal_pending(current)) {
+ if ((state == TASK_INTERRUPTIBLE &&
+ signal_pending(current)) ||
+ (state == TASK_KILLABLE &&
+ fatal_signal_pending(current))) {
__remove_wait_queue(&x->wait, &wait);
return -ERESTARTSYS;
}
}
EXPORT_SYMBOL(wait_for_completion_interruptible_timeout);
+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);
+
static long __sched
sleep_on_common(wait_queue_head_t *q, int state, long timeout)
{
unsigned long flags;
int oldprio, on_rq, running;
struct rq *rq;
+ const struct sched_class *prev_class = p->sched_class;
BUG_ON(prio < 0 || prio > MAX_PRIO);
if (on_rq) {
if (running)
p->sched_class->set_curr_task(rq);
+
enqueue_task(rq, p, 0);
- /*
- * Reschedule if we are currently running on this runqueue and
- * our priority decreased, or if we are not currently running on
- * this runqueue and our priority is higher than the current's
- */
- if (running) {
- if (p->prio > oldprio)
- resched_task(rq->curr);
- } else {
- check_preempt_curr(rq, p);
- }
+
+ check_class_changed(rq, p, prev_class, oldprio, running);
}
task_rq_unlock(rq, &flags);
}
{
int retval, oldprio, oldpolicy = -1, on_rq, running;
unsigned long flags;
+ const struct sched_class *prev_class = p->sched_class;
struct rq *rq;
/* may grab non-irq protected spin_locks */
if (on_rq) {
if (running)
p->sched_class->set_curr_task(rq);
+
activate_task(rq, p, 0);
- /*
- * Reschedule if we are currently running on this runqueue and
- * our priority decreased, or if we are not currently running on
- * this runqueue and our priority is higher than the current's
- */
- if (running) {
- if (p->prio > oldprio)
- resched_task(rq->curr);
- } else {
- check_preempt_curr(rq, p);
- }
+
+ check_class_changed(rq, p, prev_class, oldprio, running);
}
__task_rq_unlock(rq);
spin_unlock_irqrestore(&p->pi_lock, flags);
} while (need_resched());
}
-int __sched cond_resched(void)
+#if !defined(CONFIG_PREEMPT) || defined(CONFIG_PREEMPT_VOLUNTARY)
+int __sched _cond_resched(void)
{
if (need_resched() && !(preempt_count() & PREEMPT_ACTIVE) &&
system_state == SYSTEM_RUNNING) {
}
return 0;
}
-EXPORT_SYMBOL(cond_resched);
+EXPORT_SYMBOL(_cond_resched);
+#endif
/*
* cond_resched_lock() - if a reschedule is pending, drop the given lock,
*/
int cond_resched_lock(spinlock_t *lock)
{
+ int resched = need_resched() && system_state == SYSTEM_RUNNING;
int ret = 0;
- if (need_lockbreak(lock)) {
+ if (spin_needbreak(lock) || resched) {
spin_unlock(lock);
- cpu_relax();
- ret = 1;
- spin_lock(lock);
- }
- if (need_resched() && system_state == SYSTEM_RUNNING) {
- spin_release(&lock->dep_map, 1, _THIS_IP_);
- _raw_spin_unlock(lock);
- preempt_enable_no_resched();
- __cond_resched();
+ if (resched && need_resched())
+ __cond_resched();
+ else
+ cpu_relax();
ret = 1;
spin_lock(lock);
}
printk(KERN_CONT "%5lu %5d %6d\n", free,
task_pid_nr(p), task_pid_nr(p->real_parent));
- if (state != TASK_RUNNING)
- show_stack(p, NULL);
+ show_stack(p, NULL);
}
void show_state_filter(unsigned long state_filter)
spin_unlock_irqrestore(&rq->lock, 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
+
/*
* The idle tasks have their own, simple scheduling class:
*/
if (p->sched_class->set_cpus_allowed)
p->sched_class->set_cpus_allowed(p, &new_mask);
else {
- p->cpus_allowed = new_mask;
- p->nr_cpus_allowed = cpus_weight(new_mask);
+ p->cpus_allowed = new_mask;
+ p->rt.nr_cpus_allowed = cpus_weight(new_mask);
}
/* Can the task run on the task's current CPU? If so, we're done */
if (rq->rd) {
struct root_domain *old_rd = rq->rd;
- for (class = sched_class_highest; class; class = class->next)
+ for (class = sched_class_highest; class; class = class->next) {
if (class->leave_domain)
class->leave_domain(rq);
+ }
+
+ cpu_clear(rq->cpu, old_rd->span);
+ cpu_clear(rq->cpu, old_rd->online);
if (atomic_dec_and_test(&old_rd->refcount))
kfree(old_rd);
atomic_inc(&rd->refcount);
rq->rd = rd;
- for (class = sched_class_highest; class; class = class->next)
+ cpu_set(rq->cpu, rd->span);
+ if (cpu_isset(rq->cpu, cpu_online_map))
+ cpu_set(rq->cpu, rd->online);
+
+ for (class = sched_class_highest; class; class = class->next) {
if (class->join_domain)
class->join_domain(rq);
+ }
spin_unlock_irqrestore(&rq->lock, flags);
}
-static void init_rootdomain(struct root_domain *rd, const cpumask_t *map)
+static void init_rootdomain(struct root_domain *rd)
{
memset(rd, 0, sizeof(*rd));
- rd->span = *map;
- cpus_and(rd->online, rd->span, cpu_online_map);
+ cpus_clear(rd->span);
+ cpus_clear(rd->online);
}
static void init_defrootdomain(void)
{
- cpumask_t cpus = CPU_MASK_ALL;
-
- init_rootdomain(&def_root_domain, &cpus);
+ init_rootdomain(&def_root_domain);
atomic_set(&def_root_domain.refcount, 1);
}
-static struct root_domain *alloc_rootdomain(const cpumask_t *map)
+static struct root_domain *alloc_rootdomain(void)
{
struct root_domain *rd;
if (!rd)
return NULL;
- init_rootdomain(rd, map);
+ init_rootdomain(rd);
return rd;
}
/*
- * Attach the domain 'sd' to 'cpu' as its base domain. Callers must
+ * 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)
+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;
sched_group_nodes_bycpu[first_cpu(*cpu_map)] = sched_group_nodes;
#endif
- rd = alloc_rootdomain(cpu_map);
+ rd = alloc_rootdomain();
if (!rd) {
printk(KERN_WARNING "Cannot alloc root domain\n");
return -ENOMEM;
cfs_rq->min_vruntime = (u64)(-(1LL << 20));
}
+static void init_rt_rq(struct rt_rq *rt_rq, struct rq *rq)
+{
+ struct rt_prio_array *array;
+ int i;
+
+ array = &rt_rq->active;
+ for (i = 0; i < MAX_RT_PRIO; i++) {
+ INIT_LIST_HEAD(array->queue + i);
+ __clear_bit(i, array->bitmap);
+ }
+ /* delimiter for bitsearch: */
+ __set_bit(MAX_RT_PRIO, array->bitmap);
+
+#if defined CONFIG_SMP || defined CONFIG_FAIR_GROUP_SCHED
+ rt_rq->highest_prio = MAX_RT_PRIO;
+#endif
+#ifdef CONFIG_SMP
+ rt_rq->rt_nr_migratory = 0;
+ rt_rq->overloaded = 0;
+#endif
+
+ rt_rq->rt_time = 0;
+ rt_rq->rt_throttled = 0;
+
+#ifdef CONFIG_FAIR_GROUP_SCHED
+ rt_rq->rq = rq;
+#endif
+}
+
+#ifdef CONFIG_FAIR_GROUP_SCHED
+static void init_tg_cfs_entry(struct rq *rq, struct task_group *tg,
+ struct cfs_rq *cfs_rq, struct sched_entity *se,
+ int cpu, int add)
+{
+ tg->cfs_rq[cpu] = cfs_rq;
+ init_cfs_rq(cfs_rq, rq);
+ cfs_rq->tg = tg;
+ if (add)
+ list_add(&cfs_rq->leaf_cfs_rq_list, &rq->leaf_cfs_rq_list);
+
+ tg->se[cpu] = se;
+ se->cfs_rq = &rq->cfs;
+ se->my_q = cfs_rq;
+ se->load.weight = tg->shares;
+ se->load.inv_weight = div64_64(1ULL<<32, se->load.weight);
+ se->parent = NULL;
+}
+
+static void init_tg_rt_entry(struct rq *rq, struct task_group *tg,
+ struct rt_rq *rt_rq, struct sched_rt_entity *rt_se,
+ int cpu, int add)
+{
+ tg->rt_rq[cpu] = rt_rq;
+ init_rt_rq(rt_rq, rq);
+ rt_rq->tg = tg;
+ rt_rq->rt_se = rt_se;
+ if (add)
+ list_add(&rt_rq->leaf_rt_rq_list, &rq->leaf_rt_rq_list);
+
+ tg->rt_se[cpu] = rt_se;
+ rt_se->rt_rq = &rq->rt;
+ rt_se->my_q = rt_rq;
+ rt_se->parent = NULL;
+ INIT_LIST_HEAD(&rt_se->run_list);
+}
+#endif
+
void __init sched_init(void)
{
int highest_cpu = 0;
init_defrootdomain();
#endif
+#ifdef CONFIG_FAIR_GROUP_SCHED
+ list_add(&init_task_group.list, &task_groups);
+#endif
+
for_each_possible_cpu(i) {
- struct rt_prio_array *array;
struct rq *rq;
rq = cpu_rq(i);
rq->nr_running = 0;
rq->clock = 1;
init_cfs_rq(&rq->cfs, rq);
+ init_rt_rq(&rq->rt, rq);
#ifdef CONFIG_FAIR_GROUP_SCHED
- INIT_LIST_HEAD(&rq->leaf_cfs_rq_list);
- {
- struct cfs_rq *cfs_rq = &per_cpu(init_cfs_rq, i);
- struct sched_entity *se =
- &per_cpu(init_sched_entity, i);
-
- init_cfs_rq_p[i] = cfs_rq;
- init_cfs_rq(cfs_rq, rq);
- cfs_rq->tg = &init_task_group;
- list_add(&cfs_rq->leaf_cfs_rq_list,
- &rq->leaf_cfs_rq_list);
-
- init_sched_entity_p[i] = se;
- se->cfs_rq = &rq->cfs;
- se->my_q = cfs_rq;
- se->load.weight = init_task_group_load;
- se->load.inv_weight =
- div64_64(1ULL<<32, init_task_group_load);
- se->parent = NULL;
- }
init_task_group.shares = init_task_group_load;
+ INIT_LIST_HEAD(&rq->leaf_cfs_rq_list);
+ init_tg_cfs_entry(rq, &init_task_group,
+ &per_cpu(init_cfs_rq, i),
+ &per_cpu(init_sched_entity, i), i, 1);
+
+ init_task_group.rt_ratio = sysctl_sched_rt_ratio; /* XXX */
+ INIT_LIST_HEAD(&rq->leaf_rt_rq_list);
+ init_tg_rt_entry(rq, &init_task_group,
+ &per_cpu(init_rt_rq, i),
+ &per_cpu(init_sched_rt_entity, i), i, 1);
#endif
+ rq->rt_period_expire = 0;
+ rq->rt_throttled = 0;
for (j = 0; j < CPU_LOAD_IDX_MAX; j++)
rq->cpu_load[j] = 0;
#ifdef CONFIG_SMP
rq->sd = NULL;
rq->rd = NULL;
- rq_attach_root(rq, &def_root_domain);
rq->active_balance = 0;
rq->next_balance = jiffies;
rq->push_cpu = 0;
rq->cpu = i;
rq->migration_thread = NULL;
INIT_LIST_HEAD(&rq->migration_queue);
- rq->rt.highest_prio = MAX_RT_PRIO;
- rq->rt.overloaded = 0;
+ rq_attach_root(rq, &def_root_domain);
#endif
+ init_rq_hrtick(rq);
atomic_set(&rq->nr_iowait, 0);
-
- array = &rq->rt.active;
- for (j = 0; j < MAX_RT_PRIO; j++) {
- INIT_LIST_HEAD(array->queue + j);
- __clear_bit(j, array->bitmap);
- }
highest_cpu = i;
- /* delimiter for bitsearch: */
- __set_bit(MAX_RT_PRIO, array->bitmap);
}
set_load_weight(&init_task);
#ifdef CONFIG_SMP
/*
* distribute shares of all task groups among their schedulable entities,
- * to reflect load distrbution across cpus.
+ * to reflect load distribution across cpus.
*/
static int rebalance_shares(struct sched_domain *sd, int this_cpu)
{
for_each_cpu_mask(i, sdspan)
total_load += tg->cfs_rq[i]->load.weight;
- /* Nothing to do if this group has no load */
+ /* Nothing to do if this group has no load */
if (!total_load)
continue;
* sysctl_sched_max_bal_int_shares represents the maximum interval between
* consecutive calls to rebalance_shares() in the same sched domain.
*
- * These settings allows for the appropriate tradeoff between accuracy of
+ * These settings allows for the appropriate trade-off between accuracy of
* fairness and the associated overhead.
*
*/
}
#endif /* CONFIG_SMP */
+static void free_sched_group(struct task_group *tg)
+{
+ int i;
+
+ for_each_possible_cpu(i) {
+ if (tg->cfs_rq)
+ kfree(tg->cfs_rq[i]);
+ if (tg->se)
+ kfree(tg->se[i]);
+ if (tg->rt_rq)
+ kfree(tg->rt_rq[i]);
+ if (tg->rt_se)
+ kfree(tg->rt_se[i]);
+ }
+
+ kfree(tg->cfs_rq);
+ kfree(tg->se);
+ kfree(tg->rt_rq);
+ kfree(tg->rt_se);
+ kfree(tg);
+}
+
/* allocate runqueue etc for a new task group */
struct task_group *sched_create_group(void)
{
struct task_group *tg;
struct cfs_rq *cfs_rq;
struct sched_entity *se;
+ struct rt_rq *rt_rq;
+ struct sched_rt_entity *rt_se;
struct rq *rq;
int i;
tg->se = kzalloc(sizeof(se) * NR_CPUS, GFP_KERNEL);
if (!tg->se)
goto err;
+ tg->rt_rq = kzalloc(sizeof(rt_rq) * NR_CPUS, GFP_KERNEL);
+ if (!tg->rt_rq)
+ goto err;
+ tg->rt_se = kzalloc(sizeof(rt_se) * NR_CPUS, GFP_KERNEL);
+ if (!tg->rt_se)
+ goto err;
+
+ tg->shares = NICE_0_LOAD;
+ tg->rt_ratio = 0; /* XXX */
for_each_possible_cpu(i) {
rq = cpu_rq(i);
- cfs_rq = kmalloc_node(sizeof(struct cfs_rq), GFP_KERNEL,
- cpu_to_node(i));
+ cfs_rq = kmalloc_node(sizeof(struct cfs_rq),
+ GFP_KERNEL|__GFP_ZERO, cpu_to_node(i));
if (!cfs_rq)
goto err;
- se = kmalloc_node(sizeof(struct sched_entity), GFP_KERNEL,
- cpu_to_node(i));
+ se = kmalloc_node(sizeof(struct sched_entity),
+ GFP_KERNEL|__GFP_ZERO, cpu_to_node(i));
if (!se)
goto err;
- memset(cfs_rq, 0, sizeof(struct cfs_rq));
- memset(se, 0, sizeof(struct sched_entity));
+ rt_rq = kmalloc_node(sizeof(struct rt_rq),
+ GFP_KERNEL|__GFP_ZERO, cpu_to_node(i));
+ if (!rt_rq)
+ goto err;
- tg->cfs_rq[i] = cfs_rq;
- init_cfs_rq(cfs_rq, rq);
- cfs_rq->tg = tg;
+ rt_se = kmalloc_node(sizeof(struct sched_rt_entity),
+ GFP_KERNEL|__GFP_ZERO, cpu_to_node(i));
+ if (!rt_se)
+ goto err;
- tg->se[i] = se;
- se->cfs_rq = &rq->cfs;
- se->my_q = cfs_rq;
- se->load.weight = NICE_0_LOAD;
- se->load.inv_weight = div64_64(1ULL<<32, NICE_0_LOAD);
- se->parent = NULL;
+ init_tg_cfs_entry(rq, tg, cfs_rq, se, i, 0);
+ init_tg_rt_entry(rq, tg, rt_rq, rt_se, i, 0);
}
- tg->shares = NICE_0_LOAD;
-
lock_task_group_list();
for_each_possible_cpu(i) {
rq = cpu_rq(i);
cfs_rq = tg->cfs_rq[i];
list_add_rcu(&cfs_rq->leaf_cfs_rq_list, &rq->leaf_cfs_rq_list);
+ rt_rq = tg->rt_rq[i];
+ list_add_rcu(&rt_rq->leaf_rt_rq_list, &rq->leaf_rt_rq_list);
}
+ list_add_rcu(&tg->list, &task_groups);
unlock_task_group_list();
return tg;
err:
- for_each_possible_cpu(i) {
- if (tg->cfs_rq)
- kfree(tg->cfs_rq[i]);
- if (tg->se)
- kfree(tg->se[i]);
- }
- kfree(tg->cfs_rq);
- kfree(tg->se);
- kfree(tg);
-
+ free_sched_group(tg);
return ERR_PTR(-ENOMEM);
}
/* rcu callback to free various structures associated with a task group */
-static void free_sched_group(struct rcu_head *rhp)
+static void free_sched_group_rcu(struct rcu_head *rhp)
{
- struct task_group *tg = container_of(rhp, struct task_group, rcu);
- struct cfs_rq *cfs_rq;
- struct sched_entity *se;
- int i;
-
/* now it should be safe to free those cfs_rqs */
- for_each_possible_cpu(i) {
- cfs_rq = tg->cfs_rq[i];
- kfree(cfs_rq);
-
- se = tg->se[i];
- kfree(se);
- }
-
- kfree(tg->cfs_rq);
- kfree(tg->se);
- kfree(tg);
+ free_sched_group(container_of(rhp, struct task_group, rcu));
}
/* Destroy runqueue etc associated with a task group */
void sched_destroy_group(struct task_group *tg)
{
struct cfs_rq *cfs_rq = NULL;
+ struct rt_rq *rt_rq = NULL;
int i;
lock_task_group_list();
for_each_possible_cpu(i) {
cfs_rq = tg->cfs_rq[i];
list_del_rcu(&cfs_rq->leaf_cfs_rq_list);
+ rt_rq = tg->rt_rq[i];
+ list_del_rcu(&rt_rq->leaf_rt_rq_list);
}
+ list_del_rcu(&tg->list);
unlock_task_group_list();
BUG_ON(!cfs_rq);
/* wait for possible concurrent references to cfs_rqs complete */
- call_rcu(&tg->rcu, free_sched_group);
+ call_rcu(&tg->rcu, free_sched_group_rcu);
}
/* change task's runqueue when it moves between groups.
rq = task_rq_lock(tsk, &flags);
- if (tsk->sched_class != &fair_sched_class) {
- set_task_cfs_rq(tsk, task_cpu(tsk));
- goto done;
- }
-
update_rq_clock(rq);
running = task_current(rq, tsk);
tsk->sched_class->put_prev_task(rq, tsk);
}
- set_task_cfs_rq(tsk, task_cpu(tsk));
+ set_task_rq(tsk, task_cpu(tsk));
if (on_rq) {
if (unlikely(running))
enqueue_task(rq, tsk, 0);
}
-done:
task_rq_unlock(rq, &flags);
}
return tg->shares;
}
+/*
+ * Ensure the total rt_ratio <= sysctl_sched_rt_ratio
+ */
+int sched_group_set_rt_ratio(struct task_group *tg, unsigned long rt_ratio)
+{
+ struct task_group *tgi;
+ unsigned long total = 0;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(tgi, &task_groups, list)
+ total += tgi->rt_ratio;
+ rcu_read_unlock();
+
+ if (total + rt_ratio - tg->rt_ratio > sysctl_sched_rt_ratio)
+ return -EINVAL;
+
+ tg->rt_ratio = rt_ratio;
+ return 0;
+}
+
+unsigned long sched_group_rt_ratio(struct task_group *tg)
+{
+ return tg->rt_ratio;
+}
+
#endif /* CONFIG_FAIR_GROUP_SCHED */
#ifdef CONFIG_FAIR_CGROUP_SCHED
return (u64) tg->shares;
}
+static int cpu_rt_ratio_write_uint(struct cgroup *cgrp, struct cftype *cftype,
+ u64 rt_ratio_val)
+{
+ return sched_group_set_rt_ratio(cgroup_tg(cgrp), rt_ratio_val);
+}
+
+static u64 cpu_rt_ratio_read_uint(struct cgroup *cgrp, struct cftype *cft)
+{
+ struct task_group *tg = cgroup_tg(cgrp);
+
+ return (u64) tg->rt_ratio;
+}
+
static struct cftype cpu_files[] = {
{
.name = "shares",
.read_uint = cpu_shares_read_uint,
.write_uint = cpu_shares_write_uint,
},
+ {
+ .name = "rt_ratio",
+ .read_uint = cpu_rt_ratio_read_uint,
+ .write_uint = cpu_rt_ratio_write_uint,
+ },
};
static int cpu_cgroup_populate(struct cgroup_subsys *ss, struct cgroup *cont)
projects / powerpc.git / blobdiff