#include <linux/cpuset.h>
#include <linux/percpu.h>
#include <linux/kthread.h>
+#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/sysctl.h>
#include <linux/syscalls.h>
#include <linux/debugfs.h>
#include <linux/ctype.h>
#include <linux/ftrace.h>
+#include <trace/sched.h>
#include <asm/tlb.h>
#include <asm/irq_regs.h>
*/
#define RUNTIME_INF ((u64)~0ULL)
+DEFINE_TRACE(sched_wait_task);
+DEFINE_TRACE(sched_wakeup);
+DEFINE_TRACE(sched_wakeup_new);
+DEFINE_TRACE(sched_switch);
+DEFINE_TRACE(sched_migrate_task);
+
#ifdef CONFIG_SMP
/*
* Divide a load by a sched group cpu_power : (load / sg->__cpu_power)
hrtimer_init(&rt_b->rt_period_timer,
CLOCK_MONOTONIC, HRTIMER_MODE_REL);
rt_b->rt_period_timer.function = sched_rt_period_timer;
- rt_b->rt_period_timer.cb_mode = HRTIMER_CB_IRQSAFE_NO_SOFTIRQ;
+ rt_b->rt_period_timer.cb_mode = HRTIMER_CB_IRQSAFE_UNLOCKED;
+}
+
+static inline int rt_bandwidth_enabled(void)
+{
+ return sysctl_sched_rt_runtime >= 0;
}
static void start_rt_bandwidth(struct rt_bandwidth *rt_b)
{
ktime_t now;
- if (rt_b->rt_runtime == RUNTIME_INF)
+ if (rt_bandwidth_enabled() && rt_b->rt_runtime == RUNTIME_INF)
return;
if (hrtimer_active(&rt_b->rt_period_timer))
now = hrtimer_cb_get_time(&rt_b->rt_period_timer);
hrtimer_forward(&rt_b->rt_period_timer, now, rt_b->rt_period);
- hrtimer_start(&rt_b->rt_period_timer,
- rt_b->rt_period_timer.expires,
- HRTIMER_MODE_ABS);
+ hrtimer_start_expires(&rt_b->rt_period_timer,
+ HRTIMER_MODE_ABS);
}
spin_unlock(&rt_b->rt_runtime_lock);
}
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;
#endif /* CONFIG_RT_GROUP_SCHED */
-#else /* !CONFIG_FAIR_GROUP_SCHED */
+#else /* !CONFIG_USER_SCHED */
#define root_task_group init_task_group
-#endif /* CONFIG_FAIR_GROUP_SCHED */
+#endif /* CONFIG_USER_SCHED */
/* task_group_lock serializes add/remove of task groups and also changes to
* a task group's cpu shares.
u64 exec_clock;
u64 min_vruntime;
- u64 pair_start;
struct rb_root tasks_timeline;
struct rb_node *rb_leftmost;
* 'curr' points to currently running entity on this cfs_rq.
* It is set to NULL otherwise (i.e when none are currently running).
*/
- struct sched_entity *curr, *next;
+ struct sched_entity *curr, *next, *last;
- unsigned long nr_spread_over;
+ unsigned int nr_spread_over;
#ifdef CONFIG_FAIR_GROUP_SCHED
struct rq *rq; /* cpu runqueue to which this cfs_rq is attached */
#endif
#ifdef CONFIG_SCHED_HRTICK
- unsigned long hrtick_flags;
- ktime_t hrtick_expire;
+#ifdef CONFIG_SMP
+ int hrtick_csd_pending;
+ struct call_single_data hrtick_csd;
+#endif
struct hrtimer hrtick_timer;
#endif
/* BKL stats */
unsigned int bkl_count;
#endif
- struct lock_class_key rq_lock_key;
};
static DEFINE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
-static inline void check_preempt_curr(struct rq *rq, struct task_struct *p)
+static inline void check_preempt_curr(struct rq *rq, struct task_struct *p, int sync)
{
- rq->curr->sched_class->check_preempt_curr(rq, p);
+ rq->curr->sched_class->check_preempt_curr(rq, p, sync);
}
static inline int cpu_of(struct rq *rq)
/*
* ratelimit for updating the group shares.
- * default: 0.5ms
+ * default: 0.25ms
+ */
+unsigned int sysctl_sched_shares_ratelimit = 250000;
+
+/*
+ * Inject some fuzzyness into changing the per-cpu group shares
+ * this avoids remote rq-locks at the expense of fairness.
+ * default: 4
*/
-const_debug unsigned int sysctl_sched_shares_ratelimit = 500000;
+unsigned int sysctl_sched_shares_thresh = 4;
/*
* period over which we measure -rt task cpu usage in us.
static inline u64 global_rt_runtime(void)
{
- if (sysctl_sched_rt_period < 0)
+ if (sysctl_sched_rt_runtime < 0)
return RUNTIME_INF;
return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC;
}
}
+void task_rq_unlock_wait(struct task_struct *p)
+{
+ struct rq *rq = task_rq(p);
+
+ smp_mb(); /* spin-unlock-wait is not a full memory barrier */
+ spin_unlock_wait(&rq->lock);
+}
+
static void __task_rq_unlock(struct rq *rq)
__releases(rq->lock)
{
return rq;
}
-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.
* 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 */
- HRTICK_BLOCK, /* stop hrtick operations */
-};
/*
* Use hrtick when:
{
if (!sched_feat(HRTICK))
return 0;
- if (unlikely(test_bit(HRTICK_BLOCK, &rq->hrtick_flags)))
+ if (!cpu_active(cpu_of(rq)))
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))
}
/*
- * 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.
*/
}
#ifdef CONFIG_SMP
-static void hotplug_hrtick_disable(int cpu)
+/*
+ * called from hardirq (IPI) context
+ */
+static void __hrtick_start(void *arg)
{
- struct rq *rq = cpu_rq(cpu);
- unsigned long flags;
+ struct rq *rq = arg;
- spin_lock_irqsave(&rq->lock, flags);
- rq->hrtick_flags = 0;
- __set_bit(HRTICK_BLOCK, &rq->hrtick_flags);
- spin_unlock_irqrestore(&rq->lock, flags);
-
- hrtick_clear(rq);
+ spin_lock(&rq->lock);
+ hrtimer_restart(&rq->hrtick_timer);
+ rq->hrtick_csd_pending = 0;
+ spin_unlock(&rq->lock);
}
-static void hotplug_hrtick_enable(int cpu)
+/*
+ * Called to set the hrtick timer state.
+ *
+ * called with rq->lock held and irqs disabled
+ */
+static void hrtick_start(struct rq *rq, u64 delay)
{
- struct rq *rq = cpu_rq(cpu);
- unsigned long flags;
+ struct hrtimer *timer = &rq->hrtick_timer;
+ ktime_t time = ktime_add_ns(timer->base->get_time(), delay);
- spin_lock_irqsave(&rq->lock, flags);
- __clear_bit(HRTICK_BLOCK, &rq->hrtick_flags);
- spin_unlock_irqrestore(&rq->lock, flags);
+ hrtimer_set_expires(timer, time);
+
+ if (rq == this_rq()) {
+ hrtimer_restart(timer);
+ } else if (!rq->hrtick_csd_pending) {
+ __smp_call_function_single(cpu_of(rq), &rq->hrtick_csd);
+ rq->hrtick_csd_pending = 1;
+ }
}
static int
case CPU_DOWN_PREPARE_FROZEN:
case CPU_DEAD:
case CPU_DEAD_FROZEN:
- hotplug_hrtick_disable(cpu);
- return NOTIFY_OK;
-
- case CPU_UP_PREPARE:
- case CPU_UP_PREPARE_FROZEN:
- case CPU_DOWN_FAILED:
- case CPU_DOWN_FAILED_FROZEN:
- case CPU_ONLINE:
- case CPU_ONLINE_FROZEN:
- hotplug_hrtick_enable(cpu);
+ hrtick_clear(cpu_rq(cpu));
return NOTIFY_OK;
}
return NOTIFY_DONE;
}
-static void init_hrtick(void)
+static __init void init_hrtick(void)
{
hotcpu_notifier(hotplug_hrtick, 0);
}
-#endif /* CONFIG_SMP */
+#else
+/*
+ * Called to set the hrtick timer state.
+ *
+ * called with rq->lock held and irqs disabled
+ */
+static void hrtick_start(struct rq *rq, u64 delay)
+{
+ hrtimer_start(&rq->hrtick_timer, ns_to_ktime(delay), HRTIMER_MODE_REL);
+}
-static void init_rq_hrtick(struct rq *rq)
+static inline void init_hrtick(void)
{
- 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;
}
+#endif /* CONFIG_SMP */
-void hrtick_resched(void)
+static void init_rq_hrtick(struct rq *rq)
{
- struct rq *rq;
- unsigned long flags;
+#ifdef CONFIG_SMP
+ rq->hrtick_csd_pending = 0;
- if (!test_thread_flag(TIF_HRTICK_RESCHED))
- return;
+ rq->hrtick_csd.flags = 0;
+ rq->hrtick_csd.func = __hrtick_start;
+ rq->hrtick_csd.info = rq;
+#endif
- local_irq_save(flags);
- rq = cpu_rq(smp_processor_id());
- hrtick_set(rq);
- local_irq_restore(flags);
+ hrtimer_init(&rq->hrtick_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+ rq->hrtick_timer.function = hrtick;
+ rq->hrtick_timer.cb_mode = HRTIMER_CB_IRQSAFE_PERCPU;
}
-#else
+#else /* CONFIG_SCHED_HRTICK */
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)
-{
-}
-
static inline void init_hrtick(void)
{
}
-#endif
+#endif /* CONFIG_SCHED_HRTICK */
/*
* 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, int tif_bit)
+static void resched_task(struct task_struct *p)
{
int cpu;
assert_spin_locked(&task_rq(p)->lock);
- if (unlikely(test_tsk_thread_flag(p, tif_bit)))
+ if (unlikely(test_tsk_thread_flag(p, TIF_NEED_RESCHED)))
return;
- set_tsk_thread_flag(p, tif_bit);
+ set_tsk_thread_flag(p, TIF_NEED_RESCHED);
cpu = task_cpu(p);
if (cpu == smp_processor_id())
#endif /* CONFIG_NO_HZ */
#else /* !CONFIG_SMP */
-static void __resched_task(struct task_struct *p, int tif_bit)
+static void resched_task(struct task_struct *p)
{
assert_spin_locked(&task_rq(p)->lock);
- set_tsk_thread_flag(p, tif_bit);
+ set_tsk_need_resched(p);
}
#endif /* CONFIG_SMP */
update_load_sub(&rq->load, load);
}
-#ifdef CONFIG_SMP
-static unsigned long source_load(int cpu, int type);
-static unsigned long target_load(int cpu, int type);
-static int task_hot(struct task_struct *p, u64 now, struct sched_domain *sd);
-
-static unsigned long cpu_avg_load_per_task(int cpu)
-{
- struct rq *rq = cpu_rq(cpu);
-
- if (rq->nr_running)
- rq->avg_load_per_task = rq->load.weight / rq->nr_running;
-
- return rq->avg_load_per_task;
-}
-
-#ifdef CONFIG_FAIR_GROUP_SCHED
-
-typedef void (*tg_visitor)(struct task_group *, int, struct sched_domain *);
+#if (defined(CONFIG_SMP) && defined(CONFIG_FAIR_GROUP_SCHED)) || defined(CONFIG_RT_GROUP_SCHED)
+typedef int (*tg_visitor)(struct task_group *, void *);
/*
* Iterate the full tree, calling @down when first entering a node and @up when
* leaving it for the final time.
*/
-static void
-walk_tg_tree(tg_visitor down, tg_visitor up, int cpu, struct sched_domain *sd)
+static int walk_tg_tree(tg_visitor down, tg_visitor up, void *data)
{
struct task_group *parent, *child;
+ int ret;
rcu_read_lock();
parent = &root_task_group;
down:
- (*down)(parent, cpu, sd);
+ ret = (*down)(parent, data);
+ if (ret)
+ goto out_unlock;
list_for_each_entry_rcu(child, &parent->children, siblings) {
parent = child;
goto down;
up:
continue;
}
- (*up)(parent, cpu, sd);
+ ret = (*up)(parent, data);
+ if (ret)
+ goto out_unlock;
child = parent;
parent = parent->parent;
if (parent)
goto up;
+out_unlock:
rcu_read_unlock();
+
+ return ret;
+}
+
+static int tg_nop(struct task_group *tg, void *data)
+{
+ return 0;
+}
+#endif
+
+#ifdef CONFIG_SMP
+static unsigned long source_load(int cpu, int type);
+static unsigned long target_load(int cpu, int type);
+static int task_hot(struct task_struct *p, u64 now, struct sched_domain *sd);
+
+static unsigned long cpu_avg_load_per_task(int cpu)
+{
+ struct rq *rq = cpu_rq(cpu);
+ unsigned long nr_running = ACCESS_ONCE(rq->nr_running);
+
+ if (nr_running)
+ rq->avg_load_per_task = rq->load.weight / nr_running;
+ else
+ rq->avg_load_per_task = 0;
+
+ return rq->avg_load_per_task;
}
+#ifdef CONFIG_FAIR_GROUP_SCHED
+
static void __set_se_shares(struct sched_entity *se, unsigned long shares);
/*
* Calculate and set the cpu's group shares.
*/
static void
-__update_group_shares_cpu(struct task_group *tg, int cpu,
- unsigned long sd_shares, unsigned long sd_rq_weight)
+update_group_shares_cpu(struct task_group *tg, int cpu,
+ unsigned long sd_shares, unsigned long sd_rq_weight)
{
int boost = 0;
unsigned long shares;
*
*/
shares = (sd_shares * rq_weight) / (sd_rq_weight + 1);
+ shares = clamp_t(unsigned long, shares, MIN_SHARES, MAX_SHARES);
- /*
- * record the actual number of shares, not the boosted amount.
- */
- tg->cfs_rq[cpu]->shares = boost ? 0 : shares;
- tg->cfs_rq[cpu]->rq_weight = rq_weight;
+ if (abs(shares - tg->se[cpu]->load.weight) >
+ sysctl_sched_shares_thresh) {
+ struct rq *rq = cpu_rq(cpu);
+ unsigned long flags;
- if (shares < MIN_SHARES)
- shares = MIN_SHARES;
- else if (shares > MAX_SHARES)
- shares = MAX_SHARES;
+ spin_lock_irqsave(&rq->lock, flags);
+ /*
+ * record the actual number of shares, not the boosted amount.
+ */
+ tg->cfs_rq[cpu]->shares = boost ? 0 : shares;
+ tg->cfs_rq[cpu]->rq_weight = rq_weight;
- __set_se_shares(tg->se[cpu], shares);
+ __set_se_shares(tg->se[cpu], shares);
+ spin_unlock_irqrestore(&rq->lock, flags);
+ }
}
/*
* This needs to be done in a bottom-up fashion because the rq weight of a
* parent group depends on the shares of its child groups.
*/
-static void
-tg_shares_up(struct task_group *tg, int cpu, struct sched_domain *sd)
+static int tg_shares_up(struct task_group *tg, void *data)
{
unsigned long rq_weight = 0;
unsigned long shares = 0;
+ struct sched_domain *sd = data;
int i;
for_each_cpu_mask(i, sd->span) {
if (!rq_weight)
rq_weight = cpus_weight(sd->span) * NICE_0_LOAD;
- for_each_cpu_mask(i, sd->span) {
- struct rq *rq = cpu_rq(i);
- unsigned long flags;
+ for_each_cpu_mask(i, sd->span)
+ update_group_shares_cpu(tg, i, shares, rq_weight);
- spin_lock_irqsave(&rq->lock, flags);
- __update_group_shares_cpu(tg, i, shares, rq_weight);
- spin_unlock_irqrestore(&rq->lock, flags);
- }
+ return 0;
}
/*
* This needs to be done in a top-down fashion because the load of a child
* group is a fraction of its parents load.
*/
-static void
-tg_load_down(struct task_group *tg, int cpu, struct sched_domain *sd)
+static int tg_load_down(struct task_group *tg, void *data)
{
unsigned long load;
+ long cpu = (long)data;
if (!tg->parent) {
load = cpu_rq(cpu)->load.weight;
}
tg->cfs_rq[cpu]->h_load = load;
-}
-static void
-tg_nop(struct task_group *tg, int cpu, struct sched_domain *sd)
-{
+ return 0;
}
static void update_shares(struct sched_domain *sd)
if (elapsed >= (s64)(u64)sysctl_sched_shares_ratelimit) {
sd->last_update = now;
- walk_tg_tree(tg_nop, tg_shares_up, 0, sd);
+ walk_tg_tree(tg_nop, tg_shares_up, sd);
}
}
spin_lock(&rq->lock);
}
-static void update_h_load(int cpu)
+static void update_h_load(long cpu)
{
- walk_tg_tree(tg_load_down, tg_nop, cpu, NULL);
+ walk_tg_tree(tg_load_down, tg_nop, (void *)cpu);
}
#else
/*
* Buddy candidates are cache hot:
*/
- if (sched_feat(CACHE_HOT_BUDDY) && (&p->se == cfs_rq_of(&p->se)->next))
+ if (sched_feat(CACHE_HOT_BUDDY) &&
+ (&p->se == cfs_rq_of(&p->se)->next ||
+ &p->se == cfs_rq_of(&p->se)->last))
return 1;
if (p->sched_class != &fair_sched_class)
clock_offset = old_rq->clock - new_rq->clock;
+ trace_sched_migrate_task(p, task_cpu(p), new_cpu);
+
#ifdef CONFIG_SCHEDSTATS
if (p->se.wait_start)
p->se.wait_start -= clock_offset;
/*
* 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.
*/
-void wait_task_inactive(struct task_struct *p)
+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 (;;) {
* return false if the runqueue has changed and p
* is actually now running somewhere else!
*/
- while (task_running(rq, p))
+ while (task_running(rq, p)) {
+ if (match_state && unlikely(p->state != match_state))
+ return 0;
cpu_relax();
+ }
/*
* Ok, time to look more closely! We need the rq
* just go back and repeat.
*/
rq = task_rq_lock(p, &flags);
+ trace_sched_wait_task(rq, p);
running = task_running(rq, p);
on_rq = p->se.on_rq;
+ ncsw = 0;
+ if (!match_state || p->state == match_state)
+ ncsw = p->nvcsw | LONG_MIN; /* sets MSB */
task_rq_unlock(rq, &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?
*
*/
break;
}
+
+ return ncsw;
}
/***
success = 1;
out_running:
- trace_mark(kernel_sched_wakeup,
- "pid %d state %ld ## rq %p task %p rq->curr %p",
- p->pid, p->state, rq, p, rq->curr);
- check_preempt_curr(rq, p);
+ trace_sched_wakeup(rq, p);
+ check_preempt_curr(rq, p, sync);
p->state = TASK_RUNNING;
#ifdef CONFIG_SMP
p->sched_class->task_new(rq, p);
inc_nr_running(rq);
}
- trace_mark(kernel_sched_wakeup_new,
- "pid %d state %ld ## rq %p task %p rq->curr %p",
- p->pid, p->state, rq, p, rq->curr);
- check_preempt_curr(rq, p);
+ trace_sched_wakeup_new(rq, p);
+ check_preempt_curr(rq, p, 0);
#ifdef CONFIG_SMP
if (p->sched_class->task_wake_up)
p->sched_class->task_wake_up(rq, p);
struct mm_struct *mm, *oldmm;
prepare_task_switch(rq, prev, next);
- trace_mark(kernel_sched_schedule,
- "prev_pid %d next_pid %d prev_state %ld "
- "## rq %p prev %p next %p",
- prev->pid, next->pid, prev->state,
- rq, prev, next);
+ trace_sched_switch(rq, prev, next);
mm = next->mm;
oldmm = prev->active_mm;
/*
} else {
if (rq1 < rq2) {
spin_lock(&rq1->lock);
- spin_lock(&rq2->lock);
+ spin_lock_nested(&rq2->lock, SINGLE_DEPTH_NESTING);
} else {
spin_lock(&rq2->lock);
- spin_lock(&rq1->lock);
+ spin_lock_nested(&rq1->lock, SINGLE_DEPTH_NESTING);
}
}
update_rq_clock(rq1);
if (busiest < this_rq) {
spin_unlock(&this_rq->lock);
spin_lock(&busiest->lock);
- spin_lock(&this_rq->lock);
+ spin_lock_nested(&this_rq->lock, SINGLE_DEPTH_NESTING);
ret = 1;
} else
- spin_lock(&busiest->lock);
+ spin_lock_nested(&busiest->lock, SINGLE_DEPTH_NESTING);
}
return ret;
}
+static void double_unlock_balance(struct rq *this_rq, struct rq *busiest)
+ __releases(busiest->lock)
+{
+ spin_unlock(&busiest->lock);
+ lock_set_subclass(&this_rq->lock.dep_map, 0, _RET_IP_);
+}
+
/*
* If dest_cpu is allowed for this process, migrate the task to it.
* This is accomplished by forcing the cpu_allowed mask to only
rq = task_rq_lock(p, &flags);
if (!cpu_isset(dest_cpu, p->cpus_allowed)
- || unlikely(cpu_is_offline(dest_cpu)))
+ || unlikely(!cpu_active(dest_cpu)))
goto out;
/* force the process onto the specified CPU */
* Note that idle threads have a prio of MAX_PRIO, for this test
* to be always true for them.
*/
- check_preempt_curr(this_rq, p);
+ check_preempt_curr(this_rq, p, 0);
}
/*
} else
this_load_per_task = cpu_avg_load_per_task(this_cpu);
- if (max_load - this_load + 2*busiest_load_per_task >=
+ if (max_load - this_load + busiest_load_per_task >=
busiest_load_per_task * imbn) {
*imbalance = busiest_load_per_task;
return busiest;
ld_moved = move_tasks(this_rq, this_cpu, busiest,
imbalance, sd, CPU_NEWLY_IDLE,
&all_pinned);
- spin_unlock(&busiest->lock);
+ double_unlock_balance(this_rq, busiest);
if (unlikely(all_pinned)) {
cpu_clear(cpu_of(busiest), *cpus);
else
schedstat_inc(sd, alb_failed);
}
- spin_unlock(&target_rq->lock);
+ double_unlock_balance(busiest_rq, target_rq);
}
#ifdef CONFIG_NO_HZ
/*
* If we are going offline and still the leader, give up!
*/
- if (cpu_is_offline(cpu) &&
+ if (!cpu_active(cpu) &&
atomic_read(&nohz.load_balancer) == cpu) {
if (atomic_cmpxchg(&nohz.load_balancer, cpu, -1) != cpu)
BUG();
EXPORT_PER_CPU_SYMBOL(kstat);
/*
- * Return p->sum_exec_runtime plus any more ns on the sched_clock
- * that have not yet been banked in case the task is currently running.
+ * Return any ns on the sched_clock that have not yet been banked in
+ * @p in case that task is currently running.
*/
-unsigned long long task_sched_runtime(struct task_struct *p)
+unsigned long long task_delta_exec(struct task_struct *p)
{
unsigned long flags;
- u64 ns, delta_exec;
struct rq *rq;
+ u64 ns = 0;
rq = task_rq_lock(p, &flags);
- ns = p->se.sum_exec_runtime;
+
if (task_current(rq, p)) {
+ u64 delta_exec;
+
update_rq_clock(rq);
delta_exec = rq->clock - p->se.exec_start;
if ((s64)delta_exec > 0)
- ns += delta_exec;
+ ns = delta_exec;
}
+
task_rq_unlock(rq, &flags);
return ns;
cputime64_t tmp;
p->utime = cputime_add(p->utime, cputime);
+ account_group_user_time(p, cputime);
/* Add user time to cpustat. */
tmp = cputime_to_cputime64(cputime);
cpustat->nice = cputime64_add(cpustat->nice, tmp);
else
cpustat->user = cputime64_add(cpustat->user, tmp);
+ /* Account for user time used */
+ acct_update_integrals(p);
}
/*
tmp = cputime_to_cputime64(cputime);
p->utime = cputime_add(p->utime, cputime);
+ account_group_user_time(p, cputime);
p->gtime = cputime_add(p->gtime, cputime);
cpustat->user = cputime64_add(cpustat->user, tmp);
}
p->stime = cputime_add(p->stime, cputime);
+ account_group_system_time(p, cputime);
/* Add system time to cpustat. */
tmp = cputime_to_cputime64(cputime);
if (p == rq->idle) {
p->stime = cputime_add(p->stime, steal);
+ account_group_system_time(p, steal);
if (atomic_read(&rq->nr_iowait) > 0)
cpustat->iowait = cputime64_add(cpustat->iowait, tmp);
else
}
/*
+ * 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;
+
+ /*
+ * Use CFS's precise accounting:
+ */
+ 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;
+
+ /*
+ * Use CFS's precise accounting. (we subtract utime from
+ * the total, to make sure the total observed by userspace
+ * grows monotonically - apps rely on that):
+ */
+ 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;
+}
+
+/*
* This function gets called by the timer code, with HZ frequency.
* We call it with interrupts disabled.
*
struct task_struct *prev, *next;
unsigned long *switch_count;
struct rq *rq;
- int cpu, hrtick = sched_feat(HRTICK);
+ int cpu;
need_resched:
preempt_disable();
schedule_debug(prev);
- if (hrtick)
+ if (sched_feat(HRTICK))
hrtick_clear(rq);
- /*
- * Do the rq-clock update outside the rq lock:
- */
- local_irq_disable();
+ spin_lock_irq(&rq->lock);
update_rq_clock(rq);
- spin_lock(&rq->lock);
clear_tsk_need_resched(prev);
if (prev->state && !(preempt_count() & PREEMPT_ACTIVE)) {
} else
spin_unlock_irq(&rq->lock);
- if (hrtick)
- hrtick_set(rq);
-
if (unlikely(reacquire_kernel_lock(current) < 0))
goto need_resched_nonpreemptible;
}
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.
+ */
void complete(struct completion *x)
{
unsigned long 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.
+ */
void complete_all(struct completion *x)
{
unsigned long flags;
wait.flags |= WQ_FLAG_EXCLUSIVE;
__add_wait_queue_tail(&x->wait, &wait);
do {
- if ((state == TASK_INTERRUPTIBLE &&
- signal_pending(current)) ||
- (state == TASK_KILLABLE &&
- fatal_signal_pending(current))) {
+ if (signal_pending_state(state, current)) {
timeout = -ERESTARTSYS;
break;
}
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)
{
}
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);
}
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)
}
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);
}
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)
{
return -EPERM;
}
+ if (user) {
#ifdef CONFIG_RT_GROUP_SCHED
- /*
- * Do not allow realtime tasks into groups that have no runtime
- * assigned.
- */
- if (user
- && rt_policy(policy) && task_group(p)->rt_bandwidth.rt_runtime == 0)
- return -EPERM;
+ /*
+ * Do not allow realtime tasks into groups that have no runtime
+ * assigned.
+ */
+ if (rt_bandwidth_enabled() && rt_policy(policy) &&
+ task_group(p)->rt_bandwidth.rt_runtime == 0)
+ return -EPERM;
#endif
- retval = security_task_setscheduler(p, policy, param);
- if (retval)
- return retval;
+ 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:
struct rq *rq = cpu_rq(cpu);
unsigned long flags;
+ spin_lock_irqsave(&rq->lock, flags);
+
__sched_fork(idle);
idle->se.exec_start = sched_clock();
idle->cpus_allowed = cpumask_of_cpu(cpu);
__set_task_cpu(idle, cpu);
- spin_lock_irqsave(&rq->lock, flags);
rq->curr = rq->idle = idle;
#if defined(CONFIG_SMP) && defined(__ARCH_WANT_UNLOCKED_CTXSW)
idle->oncpu = 1;
* The idle tasks have their own, simple scheduling class:
*/
idle->sched_class = &idle_sched_class;
+ ftrace_graph_init_task(idle);
}
/*
sysctl_sched_latency = limit;
sysctl_sched_wakeup_granularity *= factor;
+
+ sysctl_sched_shares_ratelimit *= factor;
}
#ifdef CONFIG_SMP
struct rq *rq_dest, *rq_src;
int ret = 0, on_rq;
- if (unlikely(cpu_is_offline(dest_cpu)))
+ if (unlikely(!cpu_active(dest_cpu)))
return ret;
rq_src = cpu_rq(src_cpu);
set_task_cpu(p, dest_cpu);
if (on_rq) {
activate_task(rq_dest, p, 0);
- check_preempt_curr(rq_dest, p);
+ check_preempt_curr(rq_dest, p, 0);
}
done:
ret = 1;
static struct ctl_table *
sd_alloc_ctl_domain_table(struct sched_domain *sd)
{
- struct ctl_table *table = sd_alloc_ctl_entry(12);
+ struct ctl_table *table = sd_alloc_ctl_entry(13);
if (table == NULL)
return NULL;
sizeof(int), 0644, proc_dointvec_minmax);
set_table_entry(&table[10], "flags", &sd->flags,
sizeof(int), 0644, proc_dointvec_minmax);
- /* &table[11] is terminator */
+ set_table_entry(&table[11], "name", sd->name,
+ CORENAME_MAX_SIZE, 0444, proc_dostring);
+ /* &table[12] is terminator */
return table;
}
.priority = 10
};
-void __init migration_init(void)
+static int __init migration_init(void)
{
void *cpu = (void *)(long)smp_processor_id();
int err;
BUG_ON(err == NOTIFY_BAD);
migration_call(&migration_notifier, CPU_ONLINE, cpu);
register_cpu_notifier(&migration_notifier);
+
+ return err;
}
+early_initcall(migration_init);
#endif
#ifdef CONFIG_SMP
struct sched_domain *tmp;
/* Remove the sched domains which do not contribute to scheduling. */
- for (tmp = sd; tmp; tmp = tmp->parent) {
+ 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)) {
/* Setup the mask of cpus configured for isolated domains */
static int __init isolated_cpu_setup(char *str)
{
- int ints[NR_CPUS], i;
+ static int __initdata ints[NR_CPUS];
+ int i;
str = get_options(str, ARRAY_SIZE(ints), ints);
cpus_clear(cpu_isolated_map);
* 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)
error:
free_sched_groups(cpu_map, tmpmask);
SCHED_CPUMASK_FREE((void *)allmasks);
+ kfree(rd);
return -ENOMEM;
#endif
}
}
/*
- * Free current domain masks.
- * Called after all cpus are attached to NULL domain.
- */
-static void free_sched_domains(void)
-{
- ndoms_cur = 0;
- if (doms_cur != &fallback_doms)
- kfree(doms_cur);
- doms_cur = &fallback_doms;
-}
-
-/*
* Set up scheduler domains and groups. Callers must hold the hotplug lock.
* For now this just excludes isolated cpus, but could be used to
* exclude other special cases in the future.
*
* 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,
- * and partition_sched_domains() will fallback to the single partition
- * 'fallback_doms'.
+ * 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_map.
+ * ndoms_new == 0 is a special case for destroying existing domains,
+ * and it will not create the default domain.
*
* Call with hotplug lock held
*/
void partition_sched_domains(int ndoms_new, cpumask_t *doms_new,
struct sched_domain_attr *dattr_new)
{
- int i, j;
+ int i, j, n;
mutex_lock(&sched_domains_mutex);
/* always unregister in case we don't destroy any domains */
unregister_sched_domain_sysctl();
- if (doms_new == NULL) {
- ndoms_new = 1;
- doms_new = &fallback_doms;
- cpus_andnot(doms_new[0], cpu_online_map, cpu_isolated_map);
- dattr_new = NULL;
- }
+ n = doms_new ? ndoms_new : 0;
/* Destroy deleted domains */
for (i = 0; i < ndoms_cur; i++) {
- for (j = 0; j < ndoms_new; j++) {
+ for (j = 0; j < n; j++) {
if (cpus_equal(doms_cur[i], doms_new[j])
&& dattrs_equal(dattr_cur, i, dattr_new, j))
goto match1;
;
}
+ if (doms_new == NULL) {
+ ndoms_cur = 0;
+ doms_new = &fallback_doms;
+ cpus_andnot(doms_new[0], cpu_online_map, cpu_isolated_map);
+ dattr_new = NULL;
+ }
+
/* Build new domains */
for (i = 0; i < ndoms_new; i++) {
for (j = 0; j < ndoms_cur; j++) {
#if defined(CONFIG_SCHED_MC) || defined(CONFIG_SCHED_SMT)
int arch_reinit_sched_domains(void)
{
- int err;
-
get_online_cpus();
- mutex_lock(&sched_domains_mutex);
- detach_destroy_domains(&cpu_online_map);
- free_sched_domains();
- err = arch_init_sched_domains(&cpu_online_map);
- mutex_unlock(&sched_domains_mutex);
+
+ /* Destroy domains first to force the rebuild */
+ partition_sched_domains(0, NULL, NULL);
+
+ rebuild_sched_domains();
put_online_cpus();
- return err;
+ return 0;
}
static ssize_t sched_power_savings_store(const char *buf, size_t count, int smt)
}
#ifdef CONFIG_SCHED_MC
-static ssize_t sched_mc_power_savings_show(struct sys_device *dev,
- struct sysdev_attribute *attr, char *page)
+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 sys_device *dev,
- struct sysdev_attribute *attr,
+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_ATTR(sched_mc_power_savings, 0644, sched_mc_power_savings_show,
- sched_mc_power_savings_store);
+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 sys_device *dev,
- struct sysdev_attribute *attr, char *page)
+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 sys_device *dev,
- struct sysdev_attribute *attr,
+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_ATTR(sched_smt_power_savings, 0644, sched_smt_power_savings_show,
+static SYSDEV_CLASS_ATTR(sched_smt_power_savings, 0644,
+ sched_smt_power_savings_show,
sched_smt_power_savings_store);
#endif
}
#endif /* CONFIG_SCHED_MC || CONFIG_SCHED_SMT */
+#ifndef CONFIG_CPUSETS
/*
- * Force a reinitialization of the sched domains hierarchy. The domains
- * and groups cannot be updated in place without racing with the balancing
- * code, so we temporarily attach all running cpus to the NULL domain
- * which will prevent rebalancing while the sched domains are recalculated.
+ * 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)
+{
int cpu = (int)(long)hcpu;
switch (action) {
case CPU_DOWN_PREPARE:
case CPU_DOWN_PREPARE_FROZEN:
disable_runtime(cpu_rq(cpu));
- /* fall-through */
- case CPU_UP_PREPARE:
- case CPU_UP_PREPARE_FROZEN:
- detach_destroy_domains(&cpu_online_map);
- free_sched_domains();
return NOTIFY_OK;
-
case CPU_DOWN_FAILED:
case CPU_DOWN_FAILED_FROZEN:
case CPU_ONLINE:
case CPU_ONLINE_FROZEN:
enable_runtime(cpu_rq(cpu));
- /* fall-through */
- case CPU_UP_CANCELED:
- case CPU_UP_CANCELED_FROZEN:
- case CPU_DEAD:
- case CPU_DEAD_FROZEN:
- /*
- * Fall through and re-initialise the domains.
- */
- break;
+ return NOTIFY_OK;
+
default:
return NOTIFY_DONE;
}
-
-#ifndef CONFIG_CPUSETS
- /*
- * Create default domain partitioning if cpusets are disabled.
- * Otherwise we let cpusets rebuild the domains based on the
- * current setup.
- */
-
- /* The hotplug lock is already held by cpu_up/cpu_down */
- arch_init_sched_domains(&cpu_online_map);
-#endif
-
- return NOTIFY_OK;
}
void __init sched_init_smp(void)
cpu_set(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);
+
init_hrtick();
/* Move init over to a non-isolated CPU */
rq = cpu_rq(i);
spin_lock_init(&rq->lock);
- lockdep_set_class(&rq->lock, &rq->rq_lock_key);
rq->nr_running = 0;
init_cfs_rq(&rq->cfs, rq);
init_rt_rq(&rq->rt, rq);
#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();
- }
+ if ((!in_atomic() && !irqs_disabled()) ||
+ system_state != SYSTEM_RUNNING || oops_in_progress)
+ return;
+ if (time_before(jiffies, prev_jiffy + HZ) && prev_jiffy)
+ return;
+ prev_jiffy = jiffies;
+
+ printk(KERN_ERR
+ "BUG: sleeping function called from invalid context at %s:%d\n",
+ file, line);
+ printk(KERN_ERR
+ "in_atomic(): %d, irqs_disabled(): %d, pid: %d, name: %s\n",
+ in_atomic(), irqs_disabled(),
+ current->pid, current->comm);
+
+ debug_show_held_locks(current);
+ if (irqs_disabled())
+ print_irqtrace_events(current);
+ dump_stack();
#endif
}
EXPORT_SYMBOL(__might_sleep);
WARN_ON(!parent); /* root should already exist */
tg->parent = parent;
- list_add_rcu(&tg->siblings, &parent->children);
INIT_LIST_HEAD(&tg->children);
+ list_add_rcu(&tg->siblings, &parent->children);
spin_unlock_irqrestore(&task_group_lock, flags);
return tg;
static unsigned long to_ratio(u64 period, u64 runtime)
{
if (runtime == RUNTIME_INF)
- return 1ULL << 16;
+ return 1ULL << 20;
- return div64_u64(runtime << 16, period);
+ return div64_u64(runtime << 20, period);
}
-#ifdef CONFIG_CGROUP_SCHED
-static int __rt_schedulable(struct task_group *tg, u64 period, u64 runtime)
+/* Must be called with tasklist_lock held */
+static inline int tg_has_rt_tasks(struct task_group *tg)
{
- struct task_group *tgi, *parent = tg->parent;
- unsigned long total = 0;
+ struct task_struct *g, *p;
- if (!parent) {
- if (global_rt_period() < period)
- return 0;
+ do_each_thread(g, p) {
+ if (rt_task(p) && rt_rq_of_se(&p->rt)->tg == tg)
+ return 1;
+ } while_each_thread(g, p);
- return to_ratio(period, runtime) <
- to_ratio(global_rt_period(), global_rt_runtime());
- }
+ return 0;
+}
- if (ktime_to_ns(parent->rt_bandwidth.rt_period) < period)
- return 0;
+struct rt_schedulable_data {
+ struct task_group *tg;
+ u64 rt_period;
+ u64 rt_runtime;
+};
- rcu_read_lock();
- list_for_each_entry_rcu(tgi, &parent->children, siblings) {
- if (tgi == tg)
- continue;
+static int tg_schedulable(struct task_group *tg, void *data)
+{
+ struct rt_schedulable_data *d = data;
+ struct task_group *child;
+ unsigned long total, sum = 0;
+ u64 period, runtime;
+
+ period = ktime_to_ns(tg->rt_bandwidth.rt_period);
+ runtime = tg->rt_bandwidth.rt_runtime;
- total += to_ratio(ktime_to_ns(tgi->rt_bandwidth.rt_period),
- tgi->rt_bandwidth.rt_runtime);
+ if (tg == d->tg) {
+ period = d->rt_period;
+ runtime = d->rt_runtime;
}
- rcu_read_unlock();
- return total + to_ratio(period, runtime) <=
- to_ratio(ktime_to_ns(parent->rt_bandwidth.rt_period),
- parent->rt_bandwidth.rt_runtime);
-}
-#elif defined CONFIG_USER_SCHED
-static int __rt_schedulable(struct task_group *tg, u64 period, u64 runtime)
-{
- struct task_group *tgi;
- unsigned long total = 0;
- unsigned long global_ratio =
- to_ratio(global_rt_period(), global_rt_runtime());
+ /*
+ * Cannot have more runtime than the period.
+ */
+ if (runtime > period && runtime != RUNTIME_INF)
+ return -EINVAL;
- rcu_read_lock();
- list_for_each_entry_rcu(tgi, &task_groups, list) {
- if (tgi == tg)
- continue;
+ /*
+ * Ensure we don't starve existing RT tasks.
+ */
+ if (rt_bandwidth_enabled() && !runtime && tg_has_rt_tasks(tg))
+ return -EBUSY;
+
+ total = to_ratio(period, runtime);
- total += to_ratio(ktime_to_ns(tgi->rt_bandwidth.rt_period),
- tgi->rt_bandwidth.rt_runtime);
+ /*
+ * Nobody can have more than the global setting allows.
+ */
+ if (total > to_ratio(global_rt_period(), global_rt_runtime()))
+ return -EINVAL;
+
+ /*
+ * The sum of our children's runtime should not exceed our own.
+ */
+ list_for_each_entry_rcu(child, &tg->children, siblings) {
+ period = ktime_to_ns(child->rt_bandwidth.rt_period);
+ runtime = child->rt_bandwidth.rt_runtime;
+
+ if (child == d->tg) {
+ period = d->rt_period;
+ runtime = d->rt_runtime;
+ }
+
+ sum += to_ratio(period, runtime);
}
- rcu_read_unlock();
- return total + to_ratio(period, runtime) < global_ratio;
+ if (sum > total)
+ return -EINVAL;
+
+ return 0;
}
-#endif
-/* Must be called with tasklist_lock held */
-static inline int tg_has_rt_tasks(struct task_group *tg)
+static int __rt_schedulable(struct task_group *tg, u64 period, u64 runtime)
{
- struct task_struct *g, *p;
- do_each_thread(g, p) {
- if (rt_task(p) && rt_rq_of_se(&p->rt)->tg == tg)
- return 1;
- } while_each_thread(g, p);
- return 0;
+ struct rt_schedulable_data data = {
+ .tg = tg,
+ .rt_period = period,
+ .rt_runtime = runtime,
+ };
+
+ return walk_tg_tree(tg_schedulable, tg_nop, &data);
}
static int tg_set_bandwidth(struct task_group *tg,
mutex_lock(&rt_constraints_mutex);
read_lock(&tasklist_lock);
- if (rt_runtime == 0 && tg_has_rt_tasks(tg)) {
- err = -EBUSY;
+ err = __rt_schedulable(tg, rt_period, rt_runtime);
+ if (err)
goto unlock;
- }
- if (!__rt_schedulable(tg, rt_period, rt_runtime)) {
- err = -EINVAL;
- goto unlock;
- }
spin_lock_irq(&tg->rt_bandwidth.rt_runtime_lock);
tg->rt_bandwidth.rt_period = ns_to_ktime(rt_period);
static int sched_rt_global_constraints(void)
{
- struct task_group *tg = &root_task_group;
- u64 rt_runtime, rt_period;
+ u64 runtime, period;
int ret = 0;
- rt_period = ktime_to_ns(tg->rt_bandwidth.rt_period);
- rt_runtime = tg->rt_bandwidth.rt_runtime;
+ if (sysctl_sched_rt_period <= 0)
+ return -EINVAL;
+
+ runtime = global_rt_runtime();
+ period = global_rt_period();
+
+ /*
+ * Sanity check on the sysctl variables.
+ */
+ if (runtime > period && runtime != RUNTIME_INF)
+ return -EINVAL;
mutex_lock(&rt_constraints_mutex);
- if (!__rt_schedulable(tg, rt_period, rt_runtime))
- ret = -EINVAL;
+ read_lock(&tasklist_lock);
+ ret = __rt_schedulable(NULL, 0, 0);
+ read_unlock(&tasklist_lock);
mutex_unlock(&rt_constraints_mutex);
return ret;
unsigned long flags;
int i;
+ if (sysctl_sched_rt_period <= 0)
+ return -EINVAL;
+
spin_lock_irqsave(&def_rt_bandwidth.rt_runtime_lock, flags);
for_each_possible_cpu(i) {
struct rt_rq *rt_rq = &cpu_rq(i)->rt;
if (!cgrp->parent) {
/* This is early initialization for the top cgroup */
- init_task_group.css.cgroup = cgrp;
return &init_task_group.css;
}
if (IS_ERR(tg))
return ERR_PTR(-ENOMEM);
- /* Bind the cgroup to task_group object we just created */
- tg->css.cgroup = cgrp;
-
return &tg->css;
}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff