Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (46 commits)
  llist: Add back llist_add_batch() and llist_del_first() prototypes
  sched: Don't use tasklist_lock for debug prints
  sched: Warn on rt throttling
  sched: Unify the ->cpus_allowed mask copy
  sched: Wrap scheduler p->cpus_allowed access
  sched: Request for idle balance during nohz idle load balance
  sched: Use resched IPI to kick off the nohz idle balance
  sched: Fix idle_cpu()
  llist: Remove cpu_relax() usage in cmpxchg loops
  sched: Convert to struct llist
  llist: Add llist_next()
  irq_work: Use llist in the struct irq_work logic
  llist: Return whether list is empty before adding in llist_add()
  llist: Move cpu_relax() to after the cmpxchg()
  llist: Remove the platform-dependent NMI checks
  llist: Make some llist functions inline
  sched, tracing: Show PREEMPT_ACTIVE state in trace_sched_switch
  sched: Remove redundant test in check_preempt_tick()
  sched: Add documentation for bandwidth control
  sched: Return unused runtime on group dequeue
  ...
This commit is contained in:
Linus Torvalds 2011-10-26 17:08:43 +02:00
commit 8a4a8918ed
20 changed files with 1645 additions and 409 deletions

View file

@ -17,54 +17,34 @@
* claimed NULL, 3 -> {pending} : claimed to be enqueued
* pending next, 3 -> {busy} : queued, pending callback
* busy NULL, 2 -> {free, claimed} : callback in progress, can be claimed
*
* We use the lower two bits of the next pointer to keep PENDING and BUSY
* flags.
*/
#define IRQ_WORK_PENDING 1UL
#define IRQ_WORK_BUSY 2UL
#define IRQ_WORK_FLAGS 3UL
static inline bool irq_work_is_set(struct irq_work *entry, int flags)
{
return (unsigned long)entry->next & flags;
}
static inline struct irq_work *irq_work_next(struct irq_work *entry)
{
unsigned long next = (unsigned long)entry->next;
next &= ~IRQ_WORK_FLAGS;
return (struct irq_work *)next;
}
static inline struct irq_work *next_flags(struct irq_work *entry, int flags)
{
unsigned long next = (unsigned long)entry;
next |= flags;
return (struct irq_work *)next;
}
static DEFINE_PER_CPU(struct irq_work *, irq_work_list);
static DEFINE_PER_CPU(struct llist_head, irq_work_list);
/*
* Claim the entry so that no one else will poke at it.
*/
static bool irq_work_claim(struct irq_work *entry)
static bool irq_work_claim(struct irq_work *work)
{
struct irq_work *next, *nflags;
unsigned long flags, nflags;
do {
next = entry->next;
if ((unsigned long)next & IRQ_WORK_PENDING)
for (;;) {
flags = work->flags;
if (flags & IRQ_WORK_PENDING)
return false;
nflags = next_flags(next, IRQ_WORK_FLAGS);
} while (cmpxchg(&entry->next, next, nflags) != next);
nflags = flags | IRQ_WORK_FLAGS;
if (cmpxchg(&work->flags, flags, nflags) == flags)
break;
cpu_relax();
}
return true;
}
void __weak arch_irq_work_raise(void)
{
/*
@ -75,20 +55,15 @@ void __weak arch_irq_work_raise(void)
/*
* Queue the entry and raise the IPI if needed.
*/
static void __irq_work_queue(struct irq_work *entry)
static void __irq_work_queue(struct irq_work *work)
{
struct irq_work *next;
bool empty;
preempt_disable();
do {
next = __this_cpu_read(irq_work_list);
/* Can assign non-atomic because we keep the flags set. */
entry->next = next_flags(next, IRQ_WORK_FLAGS);
} while (this_cpu_cmpxchg(irq_work_list, next, entry) != next);
empty = llist_add(&work->llnode, &__get_cpu_var(irq_work_list));
/* The list was empty, raise self-interrupt to start processing. */
if (!irq_work_next(entry))
if (empty)
arch_irq_work_raise();
preempt_enable();
@ -100,16 +75,16 @@ static void __irq_work_queue(struct irq_work *entry)
*
* Can be re-enqueued while the callback is still in progress.
*/
bool irq_work_queue(struct irq_work *entry)
bool irq_work_queue(struct irq_work *work)
{
if (!irq_work_claim(entry)) {
if (!irq_work_claim(work)) {
/*
* Already enqueued, can't do!
*/
return false;
}
__irq_work_queue(entry);
__irq_work_queue(work);
return true;
}
EXPORT_SYMBOL_GPL(irq_work_queue);
@ -120,34 +95,34 @@ EXPORT_SYMBOL_GPL(irq_work_queue);
*/
void irq_work_run(void)
{
struct irq_work *list;
struct irq_work *work;
struct llist_head *this_list;
struct llist_node *llnode;
if (this_cpu_read(irq_work_list) == NULL)
this_list = &__get_cpu_var(irq_work_list);
if (llist_empty(this_list))
return;
BUG_ON(!in_irq());
BUG_ON(!irqs_disabled());
list = this_cpu_xchg(irq_work_list, NULL);
llnode = llist_del_all(this_list);
while (llnode != NULL) {
work = llist_entry(llnode, struct irq_work, llnode);
while (list != NULL) {
struct irq_work *entry = list;
list = irq_work_next(list);
llnode = llist_next(llnode);
/*
* Clear the PENDING bit, after this point the @entry
* Clear the PENDING bit, after this point the @work
* can be re-used.
*/
entry->next = next_flags(NULL, IRQ_WORK_BUSY);
entry->func(entry);
work->flags = IRQ_WORK_BUSY;
work->func(work);
/*
* Clear the BUSY bit and return to the free state if
* no-one else claimed it meanwhile.
*/
(void)cmpxchg(&entry->next,
next_flags(NULL, IRQ_WORK_BUSY),
NULL);
(void)cmpxchg(&work->flags, IRQ_WORK_BUSY, 0);
}
}
EXPORT_SYMBOL_GPL(irq_work_run);
@ -156,11 +131,11 @@ EXPORT_SYMBOL_GPL(irq_work_run);
* Synchronize against the irq_work @entry, ensures the entry is not
* currently in use.
*/
void irq_work_sync(struct irq_work *entry)
void irq_work_sync(struct irq_work *work)
{
WARN_ON_ONCE(irqs_disabled());
while (irq_work_is_set(entry, IRQ_WORK_BUSY))
while (work->flags & IRQ_WORK_BUSY)
cpu_relax();
}
EXPORT_SYMBOL_GPL(irq_work_sync);

View file

@ -196,10 +196,28 @@ static inline int rt_bandwidth_enabled(void)
return sysctl_sched_rt_runtime >= 0;
}
static void start_bandwidth_timer(struct hrtimer *period_timer, ktime_t period)
{
unsigned long delta;
ktime_t soft, hard, now;
for (;;) {
if (hrtimer_active(period_timer))
break;
now = hrtimer_cb_get_time(period_timer);
hrtimer_forward(period_timer, now, period);
soft = hrtimer_get_softexpires(period_timer);
hard = hrtimer_get_expires(period_timer);
delta = ktime_to_ns(ktime_sub(hard, soft));
__hrtimer_start_range_ns(period_timer, soft, delta,
HRTIMER_MODE_ABS_PINNED, 0);
}
}
static void start_rt_bandwidth(struct rt_bandwidth *rt_b)
{
ktime_t now;
if (!rt_bandwidth_enabled() || rt_b->rt_runtime == RUNTIME_INF)
return;
@ -207,22 +225,7 @@ static void start_rt_bandwidth(struct rt_bandwidth *rt_b)
return;
raw_spin_lock(&rt_b->rt_runtime_lock);
for (;;) {
unsigned long delta;
ktime_t soft, hard;
if (hrtimer_active(&rt_b->rt_period_timer))
break;
now = hrtimer_cb_get_time(&rt_b->rt_period_timer);
hrtimer_forward(&rt_b->rt_period_timer, now, rt_b->rt_period);
soft = hrtimer_get_softexpires(&rt_b->rt_period_timer);
hard = hrtimer_get_expires(&rt_b->rt_period_timer);
delta = ktime_to_ns(ktime_sub(hard, soft));
__hrtimer_start_range_ns(&rt_b->rt_period_timer, soft, delta,
HRTIMER_MODE_ABS_PINNED, 0);
}
start_bandwidth_timer(&rt_b->rt_period_timer, rt_b->rt_period);
raw_spin_unlock(&rt_b->rt_runtime_lock);
}
@ -247,6 +250,24 @@ struct cfs_rq;
static LIST_HEAD(task_groups);
struct cfs_bandwidth {
#ifdef CONFIG_CFS_BANDWIDTH
raw_spinlock_t lock;
ktime_t period;
u64 quota, runtime;
s64 hierarchal_quota;
u64 runtime_expires;
int idle, timer_active;
struct hrtimer period_timer, slack_timer;
struct list_head throttled_cfs_rq;
/* statistics */
int nr_periods, nr_throttled;
u64 throttled_time;
#endif
};
/* task group related information */
struct task_group {
struct cgroup_subsys_state css;
@ -278,6 +299,8 @@ struct task_group {
#ifdef CONFIG_SCHED_AUTOGROUP
struct autogroup *autogroup;
#endif
struct cfs_bandwidth cfs_bandwidth;
};
/* task_group_lock serializes the addition/removal of task groups */
@ -311,7 +334,7 @@ struct task_group root_task_group;
/* CFS-related fields in a runqueue */
struct cfs_rq {
struct load_weight load;
unsigned long nr_running;
unsigned long nr_running, h_nr_running;
u64 exec_clock;
u64 min_vruntime;
@ -377,9 +400,120 @@ struct cfs_rq {
unsigned long load_contribution;
#endif
#ifdef CONFIG_CFS_BANDWIDTH
int runtime_enabled;
u64 runtime_expires;
s64 runtime_remaining;
u64 throttled_timestamp;
int throttled, throttle_count;
struct list_head throttled_list;
#endif
#endif
};
#ifdef CONFIG_FAIR_GROUP_SCHED
#ifdef CONFIG_CFS_BANDWIDTH
static inline struct cfs_bandwidth *tg_cfs_bandwidth(struct task_group *tg)
{
return &tg->cfs_bandwidth;
}
static inline u64 default_cfs_period(void);
static int do_sched_cfs_period_timer(struct cfs_bandwidth *cfs_b, int overrun);
static void do_sched_cfs_slack_timer(struct cfs_bandwidth *cfs_b);
static enum hrtimer_restart sched_cfs_slack_timer(struct hrtimer *timer)
{
struct cfs_bandwidth *cfs_b =
container_of(timer, struct cfs_bandwidth, slack_timer);
do_sched_cfs_slack_timer(cfs_b);
return HRTIMER_NORESTART;
}
static enum hrtimer_restart sched_cfs_period_timer(struct hrtimer *timer)
{
struct cfs_bandwidth *cfs_b =
container_of(timer, struct cfs_bandwidth, period_timer);
ktime_t now;
int overrun;
int idle = 0;
for (;;) {
now = hrtimer_cb_get_time(timer);
overrun = hrtimer_forward(timer, now, cfs_b->period);
if (!overrun)
break;
idle = do_sched_cfs_period_timer(cfs_b, overrun);
}
return idle ? HRTIMER_NORESTART : HRTIMER_RESTART;
}
static void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b)
{
raw_spin_lock_init(&cfs_b->lock);
cfs_b->runtime = 0;
cfs_b->quota = RUNTIME_INF;
cfs_b->period = ns_to_ktime(default_cfs_period());
INIT_LIST_HEAD(&cfs_b->throttled_cfs_rq);
hrtimer_init(&cfs_b->period_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
cfs_b->period_timer.function = sched_cfs_period_timer;
hrtimer_init(&cfs_b->slack_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
cfs_b->slack_timer.function = sched_cfs_slack_timer;
}
static void init_cfs_rq_runtime(struct cfs_rq *cfs_rq)
{
cfs_rq->runtime_enabled = 0;
INIT_LIST_HEAD(&cfs_rq->throttled_list);
}
/* requires cfs_b->lock, may release to reprogram timer */
static void __start_cfs_bandwidth(struct cfs_bandwidth *cfs_b)
{
/*
* The timer may be active because we're trying to set a new bandwidth
* period or because we're racing with the tear-down path
* (timer_active==0 becomes visible before the hrtimer call-back
* terminates). In either case we ensure that it's re-programmed
*/
while (unlikely(hrtimer_active(&cfs_b->period_timer))) {
raw_spin_unlock(&cfs_b->lock);
/* ensure cfs_b->lock is available while we wait */
hrtimer_cancel(&cfs_b->period_timer);
raw_spin_lock(&cfs_b->lock);
/* if someone else restarted the timer then we're done */
if (cfs_b->timer_active)
return;
}
cfs_b->timer_active = 1;
start_bandwidth_timer(&cfs_b->period_timer, cfs_b->period);
}
static void destroy_cfs_bandwidth(struct cfs_bandwidth *cfs_b)
{
hrtimer_cancel(&cfs_b->period_timer);
hrtimer_cancel(&cfs_b->slack_timer);
}
#else
static void init_cfs_rq_runtime(struct cfs_rq *cfs_rq) {}
static void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b) {}
static void destroy_cfs_bandwidth(struct cfs_bandwidth *cfs_b) {}
static inline struct cfs_bandwidth *tg_cfs_bandwidth(struct task_group *tg)
{
return NULL;
}
#endif /* CONFIG_CFS_BANDWIDTH */
#endif /* CONFIG_FAIR_GROUP_SCHED */
/* Real-Time classes' related field in a runqueue: */
struct rt_rq {
struct rt_prio_array active;
@ -510,7 +644,7 @@ struct rq {
unsigned long cpu_power;
unsigned char idle_at_tick;
unsigned char idle_balance;
/* For active balancing */
int post_schedule;
int active_balance;
@ -520,8 +654,6 @@ struct rq {
int cpu;
int online;
unsigned long avg_load_per_task;
u64 rt_avg;
u64 age_stamp;
u64 idle_stamp;
@ -570,7 +702,7 @@ struct rq {
#endif
#ifdef CONFIG_SMP
struct task_struct *wake_list;
struct llist_head wake_list;
#endif
};
@ -1272,6 +1404,18 @@ void wake_up_idle_cpu(int cpu)
smp_send_reschedule(cpu);
}
static inline bool got_nohz_idle_kick(void)
{
return idle_cpu(smp_processor_id()) && this_rq()->nohz_balance_kick;
}
#else /* CONFIG_NO_HZ */
static inline bool got_nohz_idle_kick(void)
{
return false;
}
#endif /* CONFIG_NO_HZ */
static u64 sched_avg_period(void)
@ -1471,24 +1615,28 @@ static inline void dec_cpu_load(struct rq *rq, unsigned long load)
update_load_sub(&rq->load, load);
}
#if (defined(CONFIG_SMP) && defined(CONFIG_FAIR_GROUP_SCHED)) || defined(CONFIG_RT_GROUP_SCHED)
#if defined(CONFIG_RT_GROUP_SCHED) || (defined(CONFIG_FAIR_GROUP_SCHED) && \
(defined(CONFIG_SMP) || defined(CONFIG_CFS_BANDWIDTH)))
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.
* Iterate task_group tree rooted at *from, calling @down when first entering a
* node and @up when leaving it for the final time.
*
* Caller must hold rcu_lock or sufficient equivalent.
*/
static int walk_tg_tree(tg_visitor down, tg_visitor up, void *data)
static int walk_tg_tree_from(struct task_group *from,
tg_visitor down, tg_visitor up, void *data)
{
struct task_group *parent, *child;
int ret;
rcu_read_lock();
parent = &root_task_group;
parent = from;
down:
ret = (*down)(parent, data);
if (ret)
goto out_unlock;
goto out;
list_for_each_entry_rcu(child, &parent->children, siblings) {
parent = child;
goto down;
@ -1497,19 +1645,29 @@ up:
continue;
}
ret = (*up)(parent, data);
if (ret)
goto out_unlock;
if (ret || parent == from)
goto out;
child = parent;
parent = parent->parent;
if (parent)
goto up;
out_unlock:
rcu_read_unlock();
out:
return ret;
}
/*
* Iterate the full tree, calling @down when first entering a node and @up when
* leaving it for the final time.
*
* Caller must hold rcu_lock or sufficient equivalent.
*/
static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data)
{
return walk_tg_tree_from(&root_task_group, down, up, data);
}
static int tg_nop(struct task_group *tg, void *data)
{
return 0;
@ -1569,11 +1727,9 @@ static unsigned long cpu_avg_load_per_task(int 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->load.weight / nr_running;
return rq->avg_load_per_task;
return 0;
}
#ifdef CONFIG_PREEMPT
@ -1806,7 +1962,6 @@ static void activate_task(struct rq *rq, struct task_struct *p, int flags)
rq->nr_uninterruptible--;
enqueue_task(rq, p, flags);
inc_nr_running(rq);
}
/*
@ -1818,7 +1973,6 @@ static void deactivate_task(struct rq *rq, struct task_struct *p, int flags)
rq->nr_uninterruptible++;
dequeue_task(rq, p, flags);
dec_nr_running(rq);
}
#ifdef CONFIG_IRQ_TIME_ACCOUNTING
@ -2390,11 +2544,11 @@ static int select_fallback_rq(int cpu, struct task_struct *p)
/* Look for allowed, online CPU in same node. */
for_each_cpu_and(dest_cpu, nodemask, cpu_active_mask)
if (cpumask_test_cpu(dest_cpu, &p->cpus_allowed))
if (cpumask_test_cpu(dest_cpu, tsk_cpus_allowed(p)))
return dest_cpu;
/* Any allowed, online CPU? */
dest_cpu = cpumask_any_and(&p->cpus_allowed, cpu_active_mask);
dest_cpu = cpumask_any_and(tsk_cpus_allowed(p), cpu_active_mask);
if (dest_cpu < nr_cpu_ids)
return dest_cpu;
@ -2431,7 +2585,7 @@ int select_task_rq(struct task_struct *p, int sd_flags, int wake_flags)
* [ this allows ->select_task() to simply return task_cpu(p) and
* not worry about this generic constraint ]
*/
if (unlikely(!cpumask_test_cpu(cpu, &p->cpus_allowed) ||
if (unlikely(!cpumask_test_cpu(cpu, tsk_cpus_allowed(p)) ||
!cpu_online(cpu)))
cpu = select_fallback_rq(task_cpu(p), p);
@ -2556,42 +2710,26 @@ static int ttwu_remote(struct task_struct *p, int wake_flags)
}
#ifdef CONFIG_SMP
static void sched_ttwu_do_pending(struct task_struct *list)
static void sched_ttwu_pending(void)
{
struct rq *rq = this_rq();
struct llist_node *llist = llist_del_all(&rq->wake_list);
struct task_struct *p;
raw_spin_lock(&rq->lock);
while (list) {
struct task_struct *p = list;
list = list->wake_entry;
while (llist) {
p = llist_entry(llist, struct task_struct, wake_entry);
llist = llist_next(llist);
ttwu_do_activate(rq, p, 0);
}
raw_spin_unlock(&rq->lock);
}
#ifdef CONFIG_HOTPLUG_CPU
static void sched_ttwu_pending(void)
{
struct rq *rq = this_rq();
struct task_struct *list = xchg(&rq->wake_list, NULL);
if (!list)
return;
sched_ttwu_do_pending(list);
}
#endif /* CONFIG_HOTPLUG_CPU */
void scheduler_ipi(void)
{
struct rq *rq = this_rq();
struct task_struct *list = xchg(&rq->wake_list, NULL);
if (!list)
if (llist_empty(&this_rq()->wake_list) && !got_nohz_idle_kick())
return;
/*
@ -2608,25 +2746,21 @@ void scheduler_ipi(void)
* somewhat pessimize the simple resched case.
*/
irq_enter();
sched_ttwu_do_pending(list);
sched_ttwu_pending();
/*
* Check if someone kicked us for doing the nohz idle load balance.
*/
if (unlikely(got_nohz_idle_kick() && !need_resched())) {
this_rq()->idle_balance = 1;
raise_softirq_irqoff(SCHED_SOFTIRQ);
}
irq_exit();
}
static void ttwu_queue_remote(struct task_struct *p, int cpu)
{
struct rq *rq = cpu_rq(cpu);
struct task_struct *next = rq->wake_list;
for (;;) {
struct task_struct *old = next;
p->wake_entry = next;
next = cmpxchg(&rq->wake_list, old, p);
if (next == old)
break;
}
if (!next)
if (llist_add(&p->wake_entry, &cpu_rq(cpu)->wake_list))
smp_send_reschedule(cpu);
}
@ -2847,20 +2981,24 @@ void sched_fork(struct task_struct *p)
*/
p->state = TASK_RUNNING;
/*
* Make sure we do not leak PI boosting priority to the child.
*/
p->prio = current->normal_prio;
/*
* Revert to default priority/policy on fork if requested.
*/
if (unlikely(p->sched_reset_on_fork)) {
if (p->policy == SCHED_FIFO || p->policy == SCHED_RR) {
if (task_has_rt_policy(p)) {
p->policy = SCHED_NORMAL;
p->normal_prio = p->static_prio;
}
if (PRIO_TO_NICE(p->static_prio) < 0) {
p->static_prio = NICE_TO_PRIO(0);
p->normal_prio = p->static_prio;
set_load_weight(p);
}
p->rt_priority = 0;
} else if (PRIO_TO_NICE(p->static_prio) < 0)
p->static_prio = NICE_TO_PRIO(0);
p->prio = p->normal_prio = __normal_prio(p);
set_load_weight(p);
/*
* We don't need the reset flag anymore after the fork. It has
@ -2869,11 +3007,6 @@ void sched_fork(struct task_struct *p)
p->sched_reset_on_fork = 0;
}
/*
* Make sure we do not leak PI boosting priority to the child.
*/
p->prio = current->normal_prio;
if (!rt_prio(p->prio))
p->sched_class = &fair_sched_class;
@ -4116,7 +4249,7 @@ void scheduler_tick(void)
perf_event_task_tick();
#ifdef CONFIG_SMP
rq->idle_at_tick = idle_cpu(cpu);
rq->idle_balance = idle_cpu(cpu);
trigger_load_balance(rq, cpu);
#endif
}
@ -4240,7 +4373,7 @@ pick_next_task(struct rq *rq)
* Optimization: we know that if all tasks are in
* the fair class we can call that function directly:
*/
if (likely(rq->nr_running == rq->cfs.nr_running)) {
if (likely(rq->nr_running == rq->cfs.h_nr_running)) {
p = fair_sched_class.pick_next_task(rq);
if (likely(p))
return p;
@ -5026,7 +5159,20 @@ EXPORT_SYMBOL(task_nice);
*/
int idle_cpu(int cpu)
{
return cpu_curr(cpu) == cpu_rq(cpu)->idle;
struct rq *rq = cpu_rq(cpu);
if (rq->curr != rq->idle)
return 0;
if (rq->nr_running)
return 0;
#ifdef CONFIG_SMP
if (!llist_empty(&rq->wake_list))
return 0;
#endif
return 1;
}
/**
@ -5876,7 +6022,7 @@ void show_state_filter(unsigned long state_filter)
printk(KERN_INFO
" task PC stack pid father\n");
#endif
read_lock(&tasklist_lock);
rcu_read_lock();
do_each_thread(g, p) {
/*
* reset the NMI-timeout, listing all files on a slow
@ -5892,7 +6038,7 @@ void show_state_filter(unsigned long state_filter)
#ifdef CONFIG_SCHED_DEBUG
sysrq_sched_debug_show();
#endif
read_unlock(&tasklist_lock);
rcu_read_unlock();
/*
* Only show locks if all tasks are dumped:
*/
@ -6007,10 +6153,9 @@ void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
{
if (p->sched_class && p->sched_class->set_cpus_allowed)
p->sched_class->set_cpus_allowed(p, new_mask);
else {
cpumask_copy(&p->cpus_allowed, new_mask);
p->rt.nr_cpus_allowed = cpumask_weight(new_mask);
}
cpumask_copy(&p->cpus_allowed, new_mask);
p->rt.nr_cpus_allowed = cpumask_weight(new_mask);
}
/*
@ -6108,7 +6253,7 @@ static int __migrate_task(struct task_struct *p, int src_cpu, int dest_cpu)
if (task_cpu(p) != src_cpu)
goto done;
/* Affinity changed (again). */
if (!cpumask_test_cpu(dest_cpu, &p->cpus_allowed))
if (!cpumask_test_cpu(dest_cpu, tsk_cpus_allowed(p)))
goto fail;
/*
@ -6189,6 +6334,30 @@ static void calc_global_load_remove(struct rq *rq)
rq->calc_load_active = 0;
}
#ifdef CONFIG_CFS_BANDWIDTH
static void unthrottle_offline_cfs_rqs(struct rq *rq)
{
struct cfs_rq *cfs_rq;
for_each_leaf_cfs_rq(rq, cfs_rq) {
struct cfs_bandwidth *cfs_b = tg_cfs_bandwidth(cfs_rq->tg);
if (!cfs_rq->runtime_enabled)
continue;
/*
* clock_task is not advancing so we just need to make sure
* there's some valid quota amount
*/
cfs_rq->runtime_remaining = cfs_b->quota;
if (cfs_rq_throttled(cfs_rq))
unthrottle_cfs_rq(cfs_rq);
}
}
#else
static void unthrottle_offline_cfs_rqs(struct rq *rq) {}
#endif
/*
* Migrate all tasks from the rq, sleeping tasks will be migrated by
* try_to_wake_up()->select_task_rq().
@ -6214,6 +6383,9 @@ static void migrate_tasks(unsigned int dead_cpu)
*/
rq->stop = NULL;
/* Ensure any throttled groups are reachable by pick_next_task */
unthrottle_offline_cfs_rqs(rq);
for ( ; ; ) {
/*
* There's this thread running, bail when that's the only
@ -7957,6 +8129,7 @@ static void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
/* allow initial update_cfs_load() to truncate */
cfs_rq->load_stamp = 1;
#endif
init_cfs_rq_runtime(cfs_rq);
tg->cfs_rq[cpu] = cfs_rq;
tg->se[cpu] = se;
@ -8096,6 +8269,7 @@ void __init sched_init(void)
* We achieve this by letting root_task_group's tasks sit
* directly in rq->cfs (i.e root_task_group->se[] = NULL).
*/
init_cfs_bandwidth(&root_task_group.cfs_bandwidth);
init_tg_cfs_entry(&root_task_group, &rq->cfs, NULL, i, NULL);
#endif /* CONFIG_FAIR_GROUP_SCHED */
@ -8125,7 +8299,6 @@ void __init sched_init(void)
rq_attach_root(rq, &def_root_domain);
#ifdef CONFIG_NO_HZ
rq->nohz_balance_kick = 0;
init_sched_softirq_csd(&per_cpu(remote_sched_softirq_cb, i));
#endif
#endif
init_rq_hrtick(rq);
@ -8336,6 +8509,8 @@ static void free_fair_sched_group(struct task_group *tg)
{
int i;
destroy_cfs_bandwidth(tg_cfs_bandwidth(tg));
for_each_possible_cpu(i) {
if (tg->cfs_rq)
kfree(tg->cfs_rq[i]);
@ -8363,6 +8538,8 @@ int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent)
tg->shares = NICE_0_LOAD;
init_cfs_bandwidth(tg_cfs_bandwidth(tg));
for_each_possible_cpu(i) {
cfs_rq = kzalloc_node(sizeof(struct cfs_rq),
GFP_KERNEL, cpu_to_node(i));
@ -8638,12 +8815,7 @@ unsigned long sched_group_shares(struct task_group *tg)
}
#endif
#ifdef CONFIG_RT_GROUP_SCHED
/*
* Ensure that the real time constraints are schedulable.
*/
static DEFINE_MUTEX(rt_constraints_mutex);
#if defined(CONFIG_RT_GROUP_SCHED) || defined(CONFIG_CFS_BANDWIDTH)
static unsigned long to_ratio(u64 period, u64 runtime)
{
if (runtime == RUNTIME_INF)
@ -8651,6 +8823,13 @@ static unsigned long to_ratio(u64 period, u64 runtime)
return div64_u64(runtime << 20, period);
}
#endif
#ifdef CONFIG_RT_GROUP_SCHED
/*
* Ensure that the real time constraints are schedulable.
*/
static DEFINE_MUTEX(rt_constraints_mutex);
/* Must be called with tasklist_lock held */
static inline int tg_has_rt_tasks(struct task_group *tg)
@ -8671,7 +8850,7 @@ struct rt_schedulable_data {
u64 rt_runtime;
};
static int tg_schedulable(struct task_group *tg, void *data)
static int tg_rt_schedulable(struct task_group *tg, void *data)
{
struct rt_schedulable_data *d = data;
struct task_group *child;
@ -8729,16 +8908,22 @@ static int tg_schedulable(struct task_group *tg, void *data)
static int __rt_schedulable(struct task_group *tg, u64 period, u64 runtime)
{
int ret;
struct rt_schedulable_data data = {
.tg = tg,
.rt_period = period,
.rt_runtime = runtime,
};
return walk_tg_tree(tg_schedulable, tg_nop, &data);
rcu_read_lock();
ret = walk_tg_tree(tg_rt_schedulable, tg_nop, &data);
rcu_read_unlock();
return ret;
}
static int tg_set_bandwidth(struct task_group *tg,
static int tg_set_rt_bandwidth(struct task_group *tg,
u64 rt_period, u64 rt_runtime)
{
int i, err = 0;
@ -8777,7 +8962,7 @@ int sched_group_set_rt_runtime(struct task_group *tg, long rt_runtime_us)
if (rt_runtime_us < 0)
rt_runtime = RUNTIME_INF;
return tg_set_bandwidth(tg, rt_period, rt_runtime);
return tg_set_rt_bandwidth(tg, rt_period, rt_runtime);
}
long sched_group_rt_runtime(struct task_group *tg)
@ -8802,7 +8987,7 @@ int sched_group_set_rt_period(struct task_group *tg, long rt_period_us)
if (rt_period == 0)
return -EINVAL;
return tg_set_bandwidth(tg, rt_period, rt_runtime);
return tg_set_rt_bandwidth(tg, rt_period, rt_runtime);
}
long sched_group_rt_period(struct task_group *tg)
@ -8992,6 +9177,238 @@ static u64 cpu_shares_read_u64(struct cgroup *cgrp, struct cftype *cft)
return (u64) scale_load_down(tg->shares);
}
#ifdef CONFIG_CFS_BANDWIDTH
static DEFINE_MUTEX(cfs_constraints_mutex);
const u64 max_cfs_quota_period = 1 * NSEC_PER_SEC; /* 1s */
const u64 min_cfs_quota_period = 1 * NSEC_PER_MSEC; /* 1ms */
static int __cfs_schedulable(struct task_group *tg, u64 period, u64 runtime);
static int tg_set_cfs_bandwidth(struct task_group *tg, u64 period, u64 quota)
{
int i, ret = 0, runtime_enabled;
struct cfs_bandwidth *cfs_b = tg_cfs_bandwidth(tg);
if (tg == &root_task_group)
return -EINVAL;
/*
* Ensure we have at some amount of bandwidth every period. This is
* to prevent reaching a state of large arrears when throttled via
* entity_tick() resulting in prolonged exit starvation.
*/
if (quota < min_cfs_quota_period || period < min_cfs_quota_period)
return -EINVAL;
/*
* Likewise, bound things on the otherside by preventing insane quota
* periods. This also allows us to normalize in computing quota
* feasibility.
*/
if (period > max_cfs_quota_period)
return -EINVAL;
mutex_lock(&cfs_constraints_mutex);
ret = __cfs_schedulable(tg, period, quota);
if (ret)
goto out_unlock;
runtime_enabled = quota != RUNTIME_INF;
raw_spin_lock_irq(&cfs_b->lock);
cfs_b->period = ns_to_ktime(period);
cfs_b->quota = quota;
__refill_cfs_bandwidth_runtime(cfs_b);
/* restart the period timer (if active) to handle new period expiry */
if (runtime_enabled && cfs_b->timer_active) {
/* force a reprogram */
cfs_b->timer_active = 0;
__start_cfs_bandwidth(cfs_b);
}
raw_spin_unlock_irq(&cfs_b->lock);
for_each_possible_cpu(i) {
struct cfs_rq *cfs_rq = tg->cfs_rq[i];
struct rq *rq = rq_of(cfs_rq);
raw_spin_lock_irq(&rq->lock);
cfs_rq->runtime_enabled = runtime_enabled;
cfs_rq->runtime_remaining = 0;
if (cfs_rq_throttled(cfs_rq))
unthrottle_cfs_rq(cfs_rq);
raw_spin_unlock_irq(&rq->lock);
}
out_unlock:
mutex_unlock(&cfs_constraints_mutex);
return ret;
}
int tg_set_cfs_quota(struct task_group *tg, long cfs_quota_us)
{
u64 quota, period;
period = ktime_to_ns(tg_cfs_bandwidth(tg)->period);
if (cfs_quota_us < 0)
quota = RUNTIME_INF;
else
quota = (u64)cfs_quota_us * NSEC_PER_USEC;
return tg_set_cfs_bandwidth(tg, period, quota);
}
long tg_get_cfs_quota(struct task_group *tg)
{
u64 quota_us;
if (tg_cfs_bandwidth(tg)->quota == RUNTIME_INF)
return -1;
quota_us = tg_cfs_bandwidth(tg)->quota;
do_div(quota_us, NSEC_PER_USEC);
return quota_us;
}
int tg_set_cfs_period(struct task_group *tg, long cfs_period_us)
{
u64 quota, period;
period = (u64)cfs_period_us * NSEC_PER_USEC;
quota = tg_cfs_bandwidth(tg)->quota;
if (period <= 0)
return -EINVAL;
return tg_set_cfs_bandwidth(tg, period, quota);
}
long tg_get_cfs_period(struct task_group *tg)
{
u64 cfs_period_us;
cfs_period_us = ktime_to_ns(tg_cfs_bandwidth(tg)->period);
do_div(cfs_period_us, NSEC_PER_USEC);
return cfs_period_us;
}
static s64 cpu_cfs_quota_read_s64(struct cgroup *cgrp, struct cftype *cft)
{
return tg_get_cfs_quota(cgroup_tg(cgrp));
}
static int cpu_cfs_quota_write_s64(struct cgroup *cgrp, struct cftype *cftype,
s64 cfs_quota_us)
{
return tg_set_cfs_quota(cgroup_tg(cgrp), cfs_quota_us);
}
static u64 cpu_cfs_period_read_u64(struct cgroup *cgrp, struct cftype *cft)
{
return tg_get_cfs_period(cgroup_tg(cgrp));
}
static int cpu_cfs_period_write_u64(struct cgroup *cgrp, struct cftype *cftype,
u64 cfs_period_us)
{
return tg_set_cfs_period(cgroup_tg(cgrp), cfs_period_us);
}
struct cfs_schedulable_data {
struct task_group *tg;
u64 period, quota;
};
/*
* normalize group quota/period to be quota/max_period
* note: units are usecs
*/
static u64 normalize_cfs_quota(struct task_group *tg,
struct cfs_schedulable_data *d)
{
u64 quota, period;
if (tg == d->tg) {
period = d->period;
quota = d->quota;
} else {
period = tg_get_cfs_period(tg);
quota = tg_get_cfs_quota(tg);
}
/* note: these should typically be equivalent */
if (quota == RUNTIME_INF || quota == -1)
return RUNTIME_INF;
return to_ratio(period, quota);
}
static int tg_cfs_schedulable_down(struct task_group *tg, void *data)
{
struct cfs_schedulable_data *d = data;
struct cfs_bandwidth *cfs_b = tg_cfs_bandwidth(tg);
s64 quota = 0, parent_quota = -1;
if (!tg->parent) {
quota = RUNTIME_INF;
} else {
struct cfs_bandwidth *parent_b = tg_cfs_bandwidth(tg->parent);
quota = normalize_cfs_quota(tg, d);
parent_quota = parent_b->hierarchal_quota;
/*
* ensure max(child_quota) <= parent_quota, inherit when no
* limit is set
*/
if (quota == RUNTIME_INF)
quota = parent_quota;
else if (parent_quota != RUNTIME_INF && quota > parent_quota)
return -EINVAL;
}
cfs_b->hierarchal_quota = quota;
return 0;
}
static int __cfs_schedulable(struct task_group *tg, u64 period, u64 quota)
{
int ret;
struct cfs_schedulable_data data = {
.tg = tg,
.period = period,
.quota = quota,
};
if (quota != RUNTIME_INF) {
do_div(data.period, NSEC_PER_USEC);
do_div(data.quota, NSEC_PER_USEC);
}
rcu_read_lock();
ret = walk_tg_tree(tg_cfs_schedulable_down, tg_nop, &data);
rcu_read_unlock();
return ret;
}
static int cpu_stats_show(struct cgroup *cgrp, struct cftype *cft,
struct cgroup_map_cb *cb)
{
struct task_group *tg = cgroup_tg(cgrp);
struct cfs_bandwidth *cfs_b = tg_cfs_bandwidth(tg);
cb->fill(cb, "nr_periods", cfs_b->nr_periods);
cb->fill(cb, "nr_throttled", cfs_b->nr_throttled);
cb->fill(cb, "throttled_time", cfs_b->throttled_time);
return 0;
}
#endif /* CONFIG_CFS_BANDWIDTH */
#endif /* CONFIG_FAIR_GROUP_SCHED */
#ifdef CONFIG_RT_GROUP_SCHED
@ -9026,6 +9443,22 @@ static struct cftype cpu_files[] = {
.write_u64 = cpu_shares_write_u64,
},
#endif
#ifdef CONFIG_CFS_BANDWIDTH
{
.name = "cfs_quota_us",
.read_s64 = cpu_cfs_quota_read_s64,
.write_s64 = cpu_cfs_quota_write_s64,
},
{
.name = "cfs_period_us",
.read_u64 = cpu_cfs_period_read_u64,
.write_u64 = cpu_cfs_period_write_u64,
},
{
.name = "stat",
.read_map = cpu_stats_show,
},
#endif
#ifdef CONFIG_RT_GROUP_SCHED
{
.name = "rt_runtime_us",
@ -9335,4 +9768,3 @@ struct cgroup_subsys cpuacct_subsys = {
.subsys_id = cpuacct_subsys_id,
};
#endif /* CONFIG_CGROUP_CPUACCT */

View file

@ -47,9 +47,6 @@ static int convert_prio(int prio)
return cpupri;
}
#define for_each_cpupri_active(array, idx) \
for_each_set_bit(idx, array, CPUPRI_NR_PRIORITIES)
/**
* cpupri_find - find the best (lowest-pri) CPU in the system
* @cp: The cpupri context
@ -71,11 +68,38 @@ int cpupri_find(struct cpupri *cp, struct task_struct *p,
int idx = 0;
int task_pri = convert_prio(p->prio);
for_each_cpupri_active(cp->pri_active, idx) {
struct cpupri_vec *vec = &cp->pri_to_cpu[idx];
if (task_pri >= MAX_RT_PRIO)
return 0;
if (idx >= task_pri)
break;
for (idx = 0; idx < task_pri; idx++) {
struct cpupri_vec *vec = &cp->pri_to_cpu[idx];
int skip = 0;
if (!atomic_read(&(vec)->count))
skip = 1;
/*
* When looking at the vector, we need to read the counter,
* do a memory barrier, then read the mask.
*
* Note: This is still all racey, but we can deal with it.
* Ideally, we only want to look at masks that are set.
*
* If a mask is not set, then the only thing wrong is that we
* did a little more work than necessary.
*
* If we read a zero count but the mask is set, because of the
* memory barriers, that can only happen when the highest prio
* task for a run queue has left the run queue, in which case,
* it will be followed by a pull. If the task we are processing
* fails to find a proper place to go, that pull request will
* pull this task if the run queue is running at a lower
* priority.
*/
smp_rmb();
/* Need to do the rmb for every iteration */
if (skip)
continue;
if (cpumask_any_and(&p->cpus_allowed, vec->mask) >= nr_cpu_ids)
continue;
@ -115,7 +139,7 @@ void cpupri_set(struct cpupri *cp, int cpu, int newpri)
{
int *currpri = &cp->cpu_to_pri[cpu];
int oldpri = *currpri;
unsigned long flags;
int do_mb = 0;
newpri = convert_prio(newpri);
@ -128,32 +152,46 @@ void cpupri_set(struct cpupri *cp, int cpu, int newpri)
* If the cpu was currently mapped to a different value, we
* need to map it to the new value then remove the old value.
* Note, we must add the new value first, otherwise we risk the
* cpu being cleared from pri_active, and this cpu could be
* missed for a push or pull.
* cpu being missed by the priority loop in cpupri_find.
*/
if (likely(newpri != CPUPRI_INVALID)) {
struct cpupri_vec *vec = &cp->pri_to_cpu[newpri];
raw_spin_lock_irqsave(&vec->lock, flags);
cpumask_set_cpu(cpu, vec->mask);
vec->count++;
if (vec->count == 1)
set_bit(newpri, cp->pri_active);
raw_spin_unlock_irqrestore(&vec->lock, flags);
/*
* When adding a new vector, we update the mask first,
* do a write memory barrier, and then update the count, to
* make sure the vector is visible when count is set.
*/
smp_mb__before_atomic_inc();
atomic_inc(&(vec)->count);
do_mb = 1;
}
if (likely(oldpri != CPUPRI_INVALID)) {
struct cpupri_vec *vec = &cp->pri_to_cpu[oldpri];
raw_spin_lock_irqsave(&vec->lock, flags);
/*
* Because the order of modification of the vec->count
* is important, we must make sure that the update
* of the new prio is seen before we decrement the
* old prio. This makes sure that the loop sees
* one or the other when we raise the priority of
* the run queue. We don't care about when we lower the
* priority, as that will trigger an rt pull anyway.
*
* We only need to do a memory barrier if we updated
* the new priority vec.
*/
if (do_mb)
smp_mb__after_atomic_inc();
vec->count--;
if (!vec->count)
clear_bit(oldpri, cp->pri_active);
/*
* When removing from the vector, we decrement the counter first
* do a memory barrier and then clear the mask.
*/
atomic_dec(&(vec)->count);
smp_mb__after_atomic_inc();
cpumask_clear_cpu(cpu, vec->mask);
raw_spin_unlock_irqrestore(&vec->lock, flags);
}
*currpri = newpri;
@ -175,8 +213,7 @@ int cpupri_init(struct cpupri *cp)
for (i = 0; i < CPUPRI_NR_PRIORITIES; i++) {
struct cpupri_vec *vec = &cp->pri_to_cpu[i];
raw_spin_lock_init(&vec->lock);
vec->count = 0;
atomic_set(&vec->count, 0);
if (!zalloc_cpumask_var(&vec->mask, GFP_KERNEL))
goto cleanup;
}

View file

@ -4,7 +4,6 @@
#include <linux/sched.h>
#define CPUPRI_NR_PRIORITIES (MAX_RT_PRIO + 2)
#define CPUPRI_NR_PRI_WORDS BITS_TO_LONGS(CPUPRI_NR_PRIORITIES)
#define CPUPRI_INVALID -1
#define CPUPRI_IDLE 0
@ -12,14 +11,12 @@
/* values 2-101 are RT priorities 0-99 */
struct cpupri_vec {
raw_spinlock_t lock;
int count;
cpumask_var_t mask;
atomic_t count;
cpumask_var_t mask;
};
struct cpupri {
struct cpupri_vec pri_to_cpu[CPUPRI_NR_PRIORITIES];
long pri_active[CPUPRI_NR_PRI_WORDS];
int cpu_to_pri[NR_CPUS];
};

File diff suppressed because it is too large Load diff

View file

@ -11,11 +11,6 @@ SCHED_FEAT(GENTLE_FAIR_SLEEPERS, 1)
*/
SCHED_FEAT(START_DEBIT, 1)
/*
* Should wakeups try to preempt running tasks.
*/
SCHED_FEAT(WAKEUP_PREEMPT, 1)
/*
* Based on load and program behaviour, see if it makes sense to place
* a newly woken task on the same cpu as the task that woke it --

View file

@ -124,21 +124,33 @@ static void dec_rt_migration(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
update_rt_migration(rt_rq);
}
static inline int has_pushable_tasks(struct rq *rq)
{
return !plist_head_empty(&rq->rt.pushable_tasks);
}
static void enqueue_pushable_task(struct rq *rq, struct task_struct *p)
{
plist_del(&p->pushable_tasks, &rq->rt.pushable_tasks);
plist_node_init(&p->pushable_tasks, p->prio);
plist_add(&p->pushable_tasks, &rq->rt.pushable_tasks);
/* Update the highest prio pushable task */
if (p->prio < rq->rt.highest_prio.next)
rq->rt.highest_prio.next = p->prio;
}
static void dequeue_pushable_task(struct rq *rq, struct task_struct *p)
{
plist_del(&p->pushable_tasks, &rq->rt.pushable_tasks);
}
static inline int has_pushable_tasks(struct rq *rq)
{
return !plist_head_empty(&rq->rt.pushable_tasks);
/* Update the new highest prio pushable task */
if (has_pushable_tasks(rq)) {
p = plist_first_entry(&rq->rt.pushable_tasks,
struct task_struct, pushable_tasks);
rq->rt.highest_prio.next = p->prio;
} else
rq->rt.highest_prio.next = MAX_RT_PRIO;
}
#else
@ -643,6 +655,7 @@ static int sched_rt_runtime_exceeded(struct rt_rq *rt_rq)
if (rt_rq->rt_time > runtime) {
rt_rq->rt_throttled = 1;
printk_once(KERN_WARNING "sched: RT throttling activated\n");
if (rt_rq_throttled(rt_rq)) {
sched_rt_rq_dequeue(rt_rq);
return 1;
@ -698,47 +711,13 @@ static void update_curr_rt(struct rq *rq)
#if defined CONFIG_SMP
static struct task_struct *pick_next_highest_task_rt(struct rq *rq, int cpu);
static inline int next_prio(struct rq *rq)
{
struct task_struct *next = pick_next_highest_task_rt(rq, rq->cpu);
if (next && rt_prio(next->prio))
return next->prio;
else
return MAX_RT_PRIO;
}
static void
inc_rt_prio_smp(struct rt_rq *rt_rq, int prio, int prev_prio)
{
struct rq *rq = rq_of_rt_rq(rt_rq);
if (prio < prev_prio) {
/*
* If the new task is higher in priority than anything on the
* run-queue, we know that the previous high becomes our
* next-highest.
*/
rt_rq->highest_prio.next = prev_prio;
if (rq->online)
cpupri_set(&rq->rd->cpupri, rq->cpu, prio);
} else if (prio == rt_rq->highest_prio.curr)
/*
* If the next task is equal in priority to the highest on
* the run-queue, then we implicitly know that the next highest
* task cannot be any lower than current
*/
rt_rq->highest_prio.next = prio;
else if (prio < rt_rq->highest_prio.next)
/*
* Otherwise, we need to recompute next-highest
*/
rt_rq->highest_prio.next = next_prio(rq);
if (rq->online && prio < prev_prio)
cpupri_set(&rq->rd->cpupri, rq->cpu, prio);
}
static void
@ -746,9 +725,6 @@ dec_rt_prio_smp(struct rt_rq *rt_rq, int prio, int prev_prio)
{
struct rq *rq = rq_of_rt_rq(rt_rq);
if (rt_rq->rt_nr_running && (prio <= rt_rq->highest_prio.next))
rt_rq->highest_prio.next = next_prio(rq);
if (rq->online && rt_rq->highest_prio.curr != prev_prio)
cpupri_set(&rq->rd->cpupri, rq->cpu, rt_rq->highest_prio.curr);
}
@ -961,6 +937,8 @@ enqueue_task_rt(struct rq *rq, struct task_struct *p, int flags)
if (!task_current(rq, p) && p->rt.nr_cpus_allowed > 1)
enqueue_pushable_task(rq, p);
inc_nr_running(rq);
}
static void dequeue_task_rt(struct rq *rq, struct task_struct *p, int flags)
@ -971,6 +949,8 @@ static void dequeue_task_rt(struct rq *rq, struct task_struct *p, int flags)
dequeue_rt_entity(rt_se);
dequeue_pushable_task(rq, p);
dec_nr_running(rq);
}
/*
@ -1017,10 +997,12 @@ select_task_rq_rt(struct task_struct *p, int sd_flag, int flags)
struct rq *rq;
int cpu;
if (sd_flag != SD_BALANCE_WAKE)
return smp_processor_id();
cpu = task_cpu(p);
/* For anything but wake ups, just return the task_cpu */
if (sd_flag != SD_BALANCE_WAKE && sd_flag != SD_BALANCE_FORK)
goto out;
rq = cpu_rq(cpu);
rcu_read_lock();
@ -1059,6 +1041,7 @@ select_task_rq_rt(struct task_struct *p, int sd_flag, int flags)
}
rcu_read_unlock();
out:
return cpu;
}
@ -1178,7 +1161,6 @@ static struct task_struct *pick_next_task_rt(struct rq *rq)
static void put_prev_task_rt(struct rq *rq, struct task_struct *p)
{
update_curr_rt(rq);
p->se.exec_start = 0;
/*
* The previous task needs to be made eligible for pushing
@ -1198,7 +1180,7 @@ static void deactivate_task(struct rq *rq, struct task_struct *p, int sleep);
static int pick_rt_task(struct rq *rq, struct task_struct *p, int cpu)
{
if (!task_running(rq, p) &&
(cpu < 0 || cpumask_test_cpu(cpu, &p->cpus_allowed)) &&
(cpu < 0 || cpumask_test_cpu(cpu, tsk_cpus_allowed(p))) &&
(p->rt.nr_cpus_allowed > 1))
return 1;
return 0;
@ -1343,7 +1325,7 @@ static struct rq *find_lock_lowest_rq(struct task_struct *task, struct rq *rq)
*/
if (unlikely(task_rq(task) != rq ||
!cpumask_test_cpu(lowest_rq->cpu,
&task->cpus_allowed) ||
tsk_cpus_allowed(task)) ||
task_running(rq, task) ||
!task->on_rq)) {
@ -1394,6 +1376,7 @@ static int push_rt_task(struct rq *rq)
{
struct task_struct *next_task;
struct rq *lowest_rq;
int ret = 0;
if (!rq->rt.overloaded)
return 0;
@ -1426,7 +1409,7 @@ retry:
if (!lowest_rq) {
struct task_struct *task;
/*
* find lock_lowest_rq releases rq->lock
* find_lock_lowest_rq releases rq->lock
* so it is possible that next_task has migrated.
*
* We need to make sure that the task is still on the same
@ -1436,12 +1419,11 @@ retry:
task = pick_next_pushable_task(rq);
if (task_cpu(next_task) == rq->cpu && task == next_task) {
/*
* If we get here, the task hasn't moved at all, but
* it has failed to push. We will not try again,
* since the other cpus will pull from us when they
* are ready.
* The task hasn't migrated, and is still the next
* eligible task, but we failed to find a run-queue
* to push it to. Do not retry in this case, since
* other cpus will pull from us when ready.
*/
dequeue_pushable_task(rq, next_task);
goto out;
}
@ -1460,6 +1442,7 @@ retry:
deactivate_task(rq, next_task, 0);
set_task_cpu(next_task, lowest_rq->cpu);
activate_task(lowest_rq, next_task, 0);
ret = 1;
resched_task(lowest_rq->curr);
@ -1468,7 +1451,7 @@ retry:
out:
put_task_struct(next_task);
return 1;
return ret;
}
static void push_rt_tasks(struct rq *rq)
@ -1626,9 +1609,6 @@ static void set_cpus_allowed_rt(struct task_struct *p,
update_rt_migration(&rq->rt);
}
cpumask_copy(&p->cpus_allowed, new_mask);
p->rt.nr_cpus_allowed = weight;
}
/* Assumes rq->lock is held */
@ -1863,4 +1843,3 @@ static void print_rt_stats(struct seq_file *m, int cpu)
rcu_read_unlock();
}
#endif /* CONFIG_SCHED_DEBUG */

View file

@ -34,11 +34,13 @@ static struct task_struct *pick_next_task_stop(struct rq *rq)
static void
enqueue_task_stop(struct rq *rq, struct task_struct *p, int flags)
{
inc_nr_running(rq);
}
static void
dequeue_task_stop(struct rq *rq, struct task_struct *p, int flags)
{
dec_nr_running(rq);
}
static void yield_task_stop(struct rq *rq)

View file

@ -379,6 +379,16 @@ static struct ctl_table kern_table[] = {
.extra2 = &one,
},
#endif
#ifdef CONFIG_CFS_BANDWIDTH
{
.procname = "sched_cfs_bandwidth_slice_us",
.data = &sysctl_sched_cfs_bandwidth_slice,
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = &one,
},
#endif
#ifdef CONFIG_PROVE_LOCKING
{
.procname = "prove_locking",