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

Browse Source 
Pull scheduler updates from Ingo Molnar:
 "The main changes in this cycle were:

   - Optimized support for Intel "Cluster-on-Die" (CoD) topologies (Dave
     Hansen)

   - Various sched/idle refinements for better idle handling (Nicolas
     Pitre, Daniel Lezcano, Chuansheng Liu, Vincent Guittot)

   - sched/numa updates and optimizations (Rik van Riel)

   - sysbench speedup (Vincent Guittot)

   - capacity calculation cleanups/refactoring (Vincent Guittot)

   - Various cleanups to thread group iteration (Oleg Nesterov)

   - Double-rq-lock removal optimization and various refactorings
     (Kirill Tkhai)

   - various sched/deadline fixes

  ... and lots of other changes"

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (72 commits)
  sched/dl: Use dl_bw_of() under rcu_read_lock_sched()
  sched/fair: Delete resched_cpu() from idle_balance()
  sched, time: Fix build error with 64 bit cputime_t on 32 bit systems
  sched: Improve sysbench performance by fixing spurious active migration
  sched/x86: Fix up typo in topology detection
  x86, sched: Add new topology for multi-NUMA-node CPUs
  sched/rt: Use resched_curr() in task_tick_rt()
  sched: Use rq->rd in sched_setaffinity() under RCU read lock
  sched: cleanup: Rename 'out_unlock' to 'out_free_new_mask'
  sched: Use dl_bw_of() under RCU read lock
  sched/fair: Remove duplicate code from can_migrate_task()
  sched, mips, ia64: Remove __ARCH_WANT_UNLOCKED_CTXSW
  sched: print_rq(): Don't use tasklist_lock
  sched: normalize_rt_tasks(): Don't use _irqsave for tasklist_lock, use task_rq_lock()
  sched: Fix the task-group check in tg_has_rt_tasks()
  sched/fair: Leverage the idle state info when choosing the "idlest" cpu
  sched: Let the scheduler see CPU idle states
  sched/deadline: Fix inter- exclusive cpusets migrations
  sched/deadline: Clear dl_entity params when setscheduling to different class
  sched/numa: Kill the wrong/dead TASK_DEAD check in task_numa_fault()
  ...
This commit is contained in:
Linus Torvalds
2014-10-13 16:23:15 +02:00
parent 13ead805c5 f10e00f4bf
commit faafcba3b5
55 changed files with 1076 additions and 553 deletions
Download Patch File Download Diff File Expand all files Collapse all files

47
kernel/exit.c
View File

@@ -115,32 +115,33 @@ static void __exit_signal(struct task_struct *tsk)
if (tsk == sig->curr_target)
sig->curr_target = next_thread(tsk);
/*
* Accumulate here the counters for all threads but the
* group leader as they die, so they can be added into
* the process-wide totals when those are taken.
* The group leader stays around as a zombie as long
* as there are other threads. When it gets reaped,
* the exit.c code will add its counts into these totals.
* We won't ever get here for the group leader, since it
* will have been the last reference on the signal_struct.
*/
task_cputime(tsk, &utime, &stime);
sig->utime += utime;
sig->stime += stime;
sig->gtime += task_gtime(tsk);
sig->min_flt += tsk->min_flt;
sig->maj_flt += tsk->maj_flt;
sig->nvcsw += tsk->nvcsw;
sig->nivcsw += tsk->nivcsw;
sig->inblock += task_io_get_inblock(tsk);
sig->oublock += task_io_get_oublock(tsk);
task_io_accounting_add(&sig->ioac, &tsk->ioac);
sig->sum_sched_runtime += tsk->se.sum_exec_runtime;
}
/*
* Accumulate here the counters for all threads but the group leader
* as they die, so they can be added into the process-wide totals
* when those are taken. The group leader stays around as a zombie as
* long as there are other threads. When it gets reaped, the exit.c
* code will add its counts into these totals. We won't ever get here
* for the group leader, since it will have been the last reference on
* the signal_struct.
*/
task_cputime(tsk, &utime, &stime);
write_seqlock(&sig->stats_lock);
sig->utime += utime;
sig->stime += stime;
sig->gtime += task_gtime(tsk);
sig->min_flt += tsk->min_flt;
sig->maj_flt += tsk->maj_flt;
sig->nvcsw += tsk->nvcsw;
sig->nivcsw += tsk->nivcsw;
sig->inblock += task_io_get_inblock(tsk);
sig->oublock += task_io_get_oublock(tsk);
task_io_accounting_add(&sig->ioac, &tsk->ioac);
sig->sum_sched_runtime += tsk->se.sum_exec_runtime;
sig->nr_threads--;
__unhash_process(tsk, group_dead);
write_sequnlock(&sig->stats_lock);
/*
* Do this under ->siglock, we can race with another thread
@@ -1046,6 +1047,7 @@ static int wait_task_zombie(struct wait_opts *wo, struct task_struct *p)
spin_lock_irq(&p->real_parent->sighand->siglock);
psig = p->real_parent->signal;
sig = p->signal;
write_seqlock(&psig->stats_lock);
psig->cutime += tgutime + sig->cutime;
psig->cstime += tgstime + sig->cstime;
psig->cgtime += task_gtime(p) + sig->gtime + sig->cgtime;
@@ -1068,6 +1070,7 @@ static int wait_task_zombie(struct wait_opts *wo, struct task_struct *p)
psig->cmaxrss = maxrss;
task_io_accounting_add(&psig->ioac, &p->ioac);
task_io_accounting_add(&psig->ioac, &sig->ioac);
write_sequnlock(&psig->stats_lock);
spin_unlock_irq(&p->real_parent->sighand->siglock);
}

13
kernel/fork.c
View File

@@ -294,11 +294,18 @@ int __weak arch_dup_task_struct(struct task_struct *dst,
return 0;
}
void set_task_stack_end_magic(struct task_struct *tsk)
{
unsigned long *stackend;
stackend = end_of_stack(tsk);
*stackend = STACK_END_MAGIC; /* for overflow detection */
}
static struct task_struct *dup_task_struct(struct task_struct *orig)
{
struct task_struct *tsk;
struct thread_info *ti;
unsigned long *stackend;
int node = tsk_fork_get_node(orig);
int err;
@@ -328,8 +335,7 @@ static struct task_struct *dup_task_struct(struct task_struct *orig)
setup_thread_stack(tsk, orig);
clear_user_return_notifier(tsk);
clear_tsk_need_resched(tsk);
stackend = end_of_stack(tsk);
*stackend = STACK_END_MAGIC; /* for overflow detection */
set_task_stack_end_magic(tsk);
#ifdef CONFIG_CC_STACKPROTECTOR
tsk->stack_canary = get_random_int();
@@ -1067,6 +1073,7 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk)
sig->curr_target = tsk;
init_sigpending(&sig->shared_pending);
INIT_LIST_HEAD(&sig->posix_timers);
seqlock_init(&sig->stats_lock);
hrtimer_init(&sig->real_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
sig->real_timer.function = it_real_fn;

5
kernel/sched/auto_group.c
View File

@@ -148,11 +148,8 @@ autogroup_move_group(struct task_struct *p, struct autogroup *ag)
if (!ACCESS_ONCE(sysctl_sched_autogroup_enabled))
goto out;
t = p;
do {
for_each_thread(p, t)
sched_move_task(t);
} while_each_thread(p, t);
out:
unlock_task_sighand(p, &flags);
autogroup_kref_put(prev);

295
kernel/sched/core.c
View File

@@ -317,9 +317,12 @@ static inline struct rq *__task_rq_lock(struct task_struct *p)
for (;;) {
rq = task_rq(p);
raw_spin_lock(&rq->lock);
if (likely(rq == task_rq(p)))
if (likely(rq == task_rq(p) && !task_on_rq_migrating(p)))
return rq;
raw_spin_unlock(&rq->lock);
while (unlikely(task_on_rq_migrating(p)))
cpu_relax();
}
}
@@ -336,10 +339,13 @@ static struct rq *task_rq_lock(struct task_struct *p, unsigned long *flags)
raw_spin_lock_irqsave(&p->pi_lock, *flags);
rq = task_rq(p);
raw_spin_lock(&rq->lock);
if (likely(rq == task_rq(p)))
if (likely(rq == task_rq(p) && !task_on_rq_migrating(p)))
return rq;
raw_spin_unlock(&rq->lock);
raw_spin_unlock_irqrestore(&p->pi_lock, *flags);
while (unlikely(task_on_rq_migrating(p)))
cpu_relax();
}
}
@@ -433,7 +439,15 @@ static void __hrtick_start(void *arg)
void hrtick_start(struct rq *rq, u64 delay)
{
struct hrtimer *timer = &rq->hrtick_timer;
ktime_t time = ktime_add_ns(timer->base->get_time(), delay);
ktime_t time;
s64 delta;
/*
* Don't schedule slices shorter than 10000ns, that just
* doesn't make sense and can cause timer DoS.
*/
delta = max_t(s64, delay, 10000LL);
time = ktime_add_ns(timer->base->get_time(), delta);
hrtimer_set_expires(timer, time);
@@ -1027,7 +1041,7 @@ void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags)
* A queue event has occurred, and we're going to schedule. In
* this case, we can save a useless back to back clock update.
*/
if (rq->curr->on_rq && test_tsk_need_resched(rq->curr))
if (task_on_rq_queued(rq->curr) && test_tsk_need_resched(rq->curr))
rq->skip_clock_update = 1;
}
@@ -1072,7 +1086,7 @@ void set_task_cpu(struct task_struct *p, unsigned int new_cpu)
static void __migrate_swap_task(struct task_struct *p, int cpu)
{
if (p->on_rq) {
if (task_on_rq_queued(p)) {
struct rq *src_rq, *dst_rq;
src_rq = task_rq(p);
@@ -1198,7 +1212,7 @@ static int migration_cpu_stop(void *data);
unsigned long wait_task_inactive(struct task_struct *p, long match_state)
{
unsigned long flags;
int running, on_rq;
int running, queued;
unsigned long ncsw;
struct rq *rq;
@@ -1236,7 +1250,7 @@ unsigned long wait_task_inactive(struct task_struct *p, long match_state)
rq = task_rq_lock(p, &flags);
trace_sched_wait_task(p);
running = task_running(rq, p);
on_rq = p->on_rq;
queued = task_on_rq_queued(p);
ncsw = 0;
if (!match_state || p->state == match_state)
ncsw = p->nvcsw | LONG_MIN; /* sets MSB */
@@ -1268,7 +1282,7 @@ unsigned long wait_task_inactive(struct task_struct *p, long match_state)
* running right now), it's preempted, and we should
* yield - it could be a while.
*/
if (unlikely(on_rq)) {
if (unlikely(queued)) {
ktime_t to = ktime_set(0, NSEC_PER_SEC/HZ);
set_current_state(TASK_UNINTERRUPTIBLE);
@@ -1462,7 +1476,7 @@ ttwu_stat(struct task_struct *p, int cpu, int wake_flags)
static void ttwu_activate(struct rq *rq, struct task_struct *p, int en_flags)
{
activate_task(rq, p, en_flags);
p->on_rq = 1;
p->on_rq = TASK_ON_RQ_QUEUED;
/* if a worker is waking up, notify workqueue */
if (p->flags & PF_WQ_WORKER)
@@ -1521,7 +1535,7 @@ static int ttwu_remote(struct task_struct *p, int wake_flags)
int ret = 0;
rq = __task_rq_lock(p);
if (p->on_rq) {
if (task_on_rq_queued(p)) {
/* check_preempt_curr() may use rq clock */
update_rq_clock(rq);
ttwu_do_wakeup(rq, p, wake_flags);
@@ -1604,6 +1618,25 @@ static void ttwu_queue_remote(struct task_struct *p, int cpu)
}
}
void wake_up_if_idle(int cpu)
{
struct rq *rq = cpu_rq(cpu);
unsigned long flags;
if (!is_idle_task(rq->curr))
return;
if (set_nr_if_polling(rq->idle)) {
trace_sched_wake_idle_without_ipi(cpu);
} else {
raw_spin_lock_irqsave(&rq->lock, flags);
if (is_idle_task(rq->curr))
smp_send_reschedule(cpu);
/* Else cpu is not in idle, do nothing here */
raw_spin_unlock_irqrestore(&rq->lock, flags);
}
}
bool cpus_share_cache(int this_cpu, int that_cpu)
{
return per_cpu(sd_llc_id, this_cpu) == per_cpu(sd_llc_id, that_cpu);
@@ -1726,7 +1759,7 @@ static void try_to_wake_up_local(struct task_struct *p)
if (!(p->state & TASK_NORMAL))
goto out;
if (!p->on_rq)
if (!task_on_rq_queued(p))
ttwu_activate(rq, p, ENQUEUE_WAKEUP);
ttwu_do_wakeup(rq, p, 0);
@@ -1759,6 +1792,20 @@ int wake_up_state(struct task_struct *p, unsigned int state)
return try_to_wake_up(p, state, 0);
}
/*
* This function clears the sched_dl_entity static params.
*/
void __dl_clear_params(struct task_struct *p)
{
struct sched_dl_entity *dl_se = &p->dl;
dl_se->dl_runtime = 0;
dl_se->dl_deadline = 0;
dl_se->dl_period = 0;
dl_se->flags = 0;
dl_se->dl_bw = 0;
}
/*
* Perform scheduler related setup for a newly forked process p.
* p is forked by current.
@@ -1783,10 +1830,7 @@ static void __sched_fork(unsigned long clone_flags, struct task_struct *p)
RB_CLEAR_NODE(&p->dl.rb_node);
hrtimer_init(&p->dl.dl_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
p->dl.dl_runtime = p->dl.runtime = 0;
p->dl.dl_deadline = p->dl.deadline = 0;
p->dl.dl_period = 0;
p->dl.flags = 0;
__dl_clear_params(p);
INIT_LIST_HEAD(&p->rt.run_list);
@@ -1961,6 +2005,8 @@ unsigned long to_ratio(u64 period, u64 runtime)
#ifdef CONFIG_SMP
inline struct dl_bw *dl_bw_of(int i)
{
rcu_lockdep_assert(rcu_read_lock_sched_held(),
"sched RCU must be held");
return &cpu_rq(i)->rd->dl_bw;
}
@@ -1969,6 +2015,8 @@ static inline int dl_bw_cpus(int i)
struct root_domain *rd = cpu_rq(i)->rd;
int cpus = 0;
rcu_lockdep_assert(rcu_read_lock_sched_held(),
"sched RCU must be held");
for_each_cpu_and(i, rd->span, cpu_active_mask)
cpus++;
@@ -2079,7 +2127,7 @@ void wake_up_new_task(struct task_struct *p)
init_task_runnable_average(p);
rq = __task_rq_lock(p);
activate_task(rq, p, 0);
p->on_rq = 1;
p->on_rq = TASK_ON_RQ_QUEUED;
trace_sched_wakeup_new(p, true);
check_preempt_curr(rq, p, WF_FORK);
#ifdef CONFIG_SMP
@@ -2271,10 +2319,6 @@ asmlinkage __visible void schedule_tail(struct task_struct *prev)
*/
post_schedule(rq);
#ifdef __ARCH_WANT_UNLOCKED_CTXSW
/* In this case, finish_task_switch does not reenable preemption */
preempt_enable();
#endif
if (current->set_child_tid)
put_user(task_pid_vnr(current), current->set_child_tid);
}
@@ -2317,9 +2361,7 @@ context_switch(struct rq *rq, struct task_struct *prev,
* of the scheduler it's an obvious special-case), so we
* do an early lockdep release here:
*/
#ifndef __ARCH_WANT_UNLOCKED_CTXSW
spin_release(&rq->lock.dep_map, 1, _THIS_IP_);
#endif
context_tracking_task_switch(prev, next);
/* Here we just switch the register state and the stack. */
@@ -2447,7 +2489,7 @@ static u64 do_task_delta_exec(struct task_struct *p, struct rq *rq)
* project cycles that may never be accounted to this
* thread, breaking clock_gettime().
*/
if (task_current(rq, p) && p->on_rq) {
if (task_current(rq, p) && task_on_rq_queued(p)) {
update_rq_clock(rq);
ns = rq_clock_task(rq) - p->se.exec_start;
if ((s64)ns < 0)
@@ -2493,7 +2535,7 @@ unsigned long long task_sched_runtime(struct task_struct *p)
* If we see ->on_cpu without ->on_rq, the task is leaving, and has
* been accounted, so we're correct here as well.
*/
if (!p->on_cpu || !p->on_rq)
if (!p->on_cpu || !task_on_rq_queued(p))
return p->se.sum_exec_runtime;
#endif
@@ -2656,6 +2698,9 @@ static noinline void __schedule_bug(struct task_struct *prev)
*/
static inline void schedule_debug(struct task_struct *prev)
{
#ifdef CONFIG_SCHED_STACK_END_CHECK
BUG_ON(unlikely(task_stack_end_corrupted(prev)));
#endif
/*
* Test if we are atomic. Since do_exit() needs to call into
* schedule() atomically, we ignore that path. Otherwise whine
@@ -2797,7 +2842,7 @@ need_resched:
switch_count = &prev->nvcsw;
}
if (prev->on_rq || rq->skip_clock_update < 0)
if (task_on_rq_queued(prev) || rq->skip_clock_update < 0)
update_rq_clock(rq);
next = pick_next_task(rq, prev);
@@ -2962,7 +3007,7 @@ EXPORT_SYMBOL(default_wake_function);
*/
void rt_mutex_setprio(struct task_struct *p, int prio)
{
int oldprio, on_rq, running, enqueue_flag = 0;
int oldprio, queued, running, enqueue_flag = 0;
struct rq *rq;
const struct sched_class *prev_class;
@@ -2991,12 +3036,12 @@ void rt_mutex_setprio(struct task_struct *p, int prio)
trace_sched_pi_setprio(p, prio);
oldprio = p->prio;
prev_class = p->sched_class;
on_rq = p->on_rq;
queued = task_on_rq_queued(p);
running = task_current(rq, p);
if (on_rq)
if (queued)
dequeue_task(rq, p, 0);
if (running)
p->sched_class->put_prev_task(rq, p);
put_prev_task(rq, p);
/*
* Boosting condition are:
@@ -3033,7 +3078,7 @@ void rt_mutex_setprio(struct task_struct *p, int prio)
if (running)
p->sched_class->set_curr_task(rq);
if (on_rq)
if (queued)
enqueue_task(rq, p, enqueue_flag);
check_class_changed(rq, p, prev_class, oldprio);
@@ -3044,7 +3089,7 @@ out_unlock:
void set_user_nice(struct task_struct *p, long nice)
{
int old_prio, delta, on_rq;
int old_prio, delta, queued;
unsigned long flags;
struct rq *rq;
@@ -3065,8 +3110,8 @@ void set_user_nice(struct task_struct *p, long nice)
p->static_prio = NICE_TO_PRIO(nice);
goto out_unlock;
}
on_rq = p->on_rq;
if (on_rq)
queued = task_on_rq_queued(p);
if (queued)
dequeue_task(rq, p, 0);
p->static_prio = NICE_TO_PRIO(nice);
@@ -3075,7 +3120,7 @@ void set_user_nice(struct task_struct *p, long nice)
p->prio = effective_prio(p);
delta = p->prio - old_prio;
if (on_rq) {
if (queued) {
enqueue_task(rq, p, 0);
/*
* If the task increased its priority or is running and
@@ -3347,7 +3392,7 @@ static int __sched_setscheduler(struct task_struct *p,
{
int newprio = dl_policy(attr->sched_policy) ? MAX_DL_PRIO - 1 :
MAX_RT_PRIO - 1 - attr->sched_priority;
int retval, oldprio, oldpolicy = -1, on_rq, running;
int retval, oldprio, oldpolicy = -1, queued, running;
int policy = attr->sched_policy;
unsigned long flags;
const struct sched_class *prev_class;
@@ -3544,19 +3589,19 @@ change:
return 0;
}
on_rq = p->on_rq;
queued = task_on_rq_queued(p);
running = task_current(rq, p);
if (on_rq)
if (queued)
dequeue_task(rq, p, 0);
if (running)
p->sched_class->put_prev_task(rq, p);
put_prev_task(rq, p);
prev_class = p->sched_class;
__setscheduler(rq, p, attr);
if (running)
p->sched_class->set_curr_task(rq);
if (on_rq) {
if (queued) {
/*
* We enqueue to tail when the priority of a task is
* increased (user space view).
@@ -3980,14 +4025,14 @@ long sched_setaffinity(pid_t pid, const struct cpumask *in_mask)
rcu_read_lock();
if (!ns_capable(__task_cred(p)->user_ns, CAP_SYS_NICE)) {
rcu_read_unlock();
goto out_unlock;
goto out_free_new_mask;
}
rcu_read_unlock();
}
retval = security_task_setscheduler(p);
if (retval)
goto out_unlock;
goto out_free_new_mask;
cpuset_cpus_allowed(p, cpus_allowed);
@@ -4000,13 +4045,14 @@ long sched_setaffinity(pid_t pid, const struct cpumask *in_mask)
* root_domain.
*/
#ifdef CONFIG_SMP
if (task_has_dl_policy(p)) {
const struct cpumask *span = task_rq(p)->rd->span;
if (dl_bandwidth_enabled() && !cpumask_subset(span, new_mask)) {
if (task_has_dl_policy(p) && dl_bandwidth_enabled()) {
rcu_read_lock();
if (!cpumask_subset(task_rq(p)->rd->span, new_mask)) {
retval = -EBUSY;
goto out_unlock;
rcu_read_unlock();
goto out_free_new_mask;
}
rcu_read_unlock();
}
#endif
again:
@@ -4024,7 +4070,7 @@ again:
goto again;
}
}
out_unlock:
out_free_new_mask:
free_cpumask_var(new_mask);
out_free_cpus_allowed:
free_cpumask_var(cpus_allowed);
@@ -4508,7 +4554,7 @@ void show_state_filter(unsigned long state_filter)
" task PC stack pid father\n");
#endif
rcu_read_lock();
do_each_thread(g, p) {
for_each_process_thread(g, p) {
/*
* reset the NMI-timeout, listing all files on a slow
* console might take a lot of time:
@@ -4516,7 +4562,7 @@ void show_state_filter(unsigned long state_filter)
touch_nmi_watchdog();
if (!state_filter || (p->state & state_filter))
sched_show_task(p);
} while_each_thread(g, p);
}
touch_all_softlockup_watchdogs();
@@ -4571,7 +4617,7 @@ void init_idle(struct task_struct *idle, int cpu)
rcu_read_unlock();
rq->curr = rq->idle = idle;
idle->on_rq = 1;
idle->on_rq = TASK_ON_RQ_QUEUED;
#if defined(CONFIG_SMP)
idle->on_cpu = 1;
#endif
@@ -4592,6 +4638,33 @@ void init_idle(struct task_struct *idle, int cpu)
}
#ifdef CONFIG_SMP
/*
* move_queued_task - move a queued task to new rq.
*
* Returns (locked) new rq. Old rq's lock is released.
*/
static struct rq *move_queued_task(struct task_struct *p, int new_cpu)
{
struct rq *rq = task_rq(p);
lockdep_assert_held(&rq->lock);
dequeue_task(rq, p, 0);
p->on_rq = TASK_ON_RQ_MIGRATING;
set_task_cpu(p, new_cpu);
raw_spin_unlock(&rq->lock);
rq = cpu_rq(new_cpu);
raw_spin_lock(&rq->lock);
BUG_ON(task_cpu(p) != new_cpu);
p->on_rq = TASK_ON_RQ_QUEUED;
enqueue_task(rq, p, 0);
check_preempt_curr(rq, p, 0);
return rq;
}
void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
{
if (p->sched_class && p->sched_class->set_cpus_allowed)
@@ -4648,14 +4721,15 @@ int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask)
goto out;
dest_cpu = cpumask_any_and(cpu_active_mask, new_mask);
if (p->on_rq) {
if (task_running(rq, p) || p->state == TASK_WAKING) {
struct migration_arg arg = { p, dest_cpu };
/* Need help from migration thread: drop lock and wait. */
task_rq_unlock(rq, p, &flags);
stop_one_cpu(cpu_of(rq), migration_cpu_stop, &arg);
tlb_migrate_finish(p->mm);
return 0;
}
} else if (task_on_rq_queued(p))
rq = move_queued_task(p, dest_cpu);
out:
task_rq_unlock(rq, p, &flags);
@@ -4676,20 +4750,20 @@ EXPORT_SYMBOL_GPL(set_cpus_allowed_ptr);
*/
static int __migrate_task(struct task_struct *p, int src_cpu, int dest_cpu)
{
struct rq *rq_dest, *rq_src;
struct rq *rq;
int ret = 0;
if (unlikely(!cpu_active(dest_cpu)))
return ret;
rq_src = cpu_rq(src_cpu);
rq_dest = cpu_rq(dest_cpu);
rq = cpu_rq(src_cpu);
raw_spin_lock(&p->pi_lock);
double_rq_lock(rq_src, rq_dest);
raw_spin_lock(&rq->lock);
/* Already moved. */
if (task_cpu(p) != src_cpu)
goto done;
/* Affinity changed (again). */
if (!cpumask_test_cpu(dest_cpu, tsk_cpus_allowed(p)))
goto fail;
@@ -4698,16 +4772,12 @@ static int __migrate_task(struct task_struct *p, int src_cpu, int dest_cpu)
* If we're not on a rq, the next wake-up will ensure we're
* placed properly.
*/
if (p->on_rq) {
dequeue_task(rq_src, p, 0);
set_task_cpu(p, dest_cpu);
enqueue_task(rq_dest, p, 0);
check_preempt_curr(rq_dest, p, 0);
}
if (task_on_rq_queued(p))
rq = move_queued_task(p, dest_cpu);
done:
ret = 1;
fail:
double_rq_unlock(rq_src, rq_dest);
raw_spin_unlock(&rq->lock);
raw_spin_unlock(&p->pi_lock);
return ret;
}
@@ -4739,22 +4809,22 @@ void sched_setnuma(struct task_struct *p, int nid)
{
struct rq *rq;
unsigned long flags;
bool on_rq, running;
bool queued, running;
rq = task_rq_lock(p, &flags);
on_rq = p->on_rq;
queued = task_on_rq_queued(p);
running = task_current(rq, p);
if (on_rq)
if (queued)
dequeue_task(rq, p, 0);
if (running)
p->sched_class->put_prev_task(rq, p);
put_prev_task(rq, p);
p->numa_preferred_nid = nid;
if (running)
p->sched_class->set_curr_task(rq);
if (on_rq)
if (queued)
enqueue_task(rq, p, 0);
task_rq_unlock(rq, p, &flags);
}
@@ -4774,6 +4844,12 @@ static int migration_cpu_stop(void *data)
* be on another cpu but it doesn't matter.
*/
local_irq_disable();
/*
* We need to explicitly wake pending tasks before running
* __migrate_task() such that we will not miss enforcing cpus_allowed
* during wakeups, see set_cpus_allowed_ptr()'s TASK_WAKING test.
*/
sched_ttwu_pending();
__migrate_task(arg->task, raw_smp_processor_id(), arg->dest_cpu);
local_irq_enable();
return 0;
@@ -5184,6 +5260,7 @@ static int sched_cpu_inactive(struct notifier_block *nfb,
{
unsigned long flags;
long cpu = (long)hcpu;
struct dl_bw *dl_b;
switch (action & ~CPU_TASKS_FROZEN) {
case CPU_DOWN_PREPARE:
@@ -5191,15 +5268,19 @@ static int sched_cpu_inactive(struct notifier_block *nfb,
/* explicitly allow suspend */
if (!(action & CPU_TASKS_FROZEN)) {
struct dl_bw *dl_b = dl_bw_of(cpu);
bool overflow;
int cpus;
rcu_read_lock_sched();
dl_b = dl_bw_of(cpu);
raw_spin_lock_irqsave(&dl_b->lock, flags);
cpus = dl_bw_cpus(cpu);
overflow = __dl_overflow(dl_b, cpus, 0, 0);
raw_spin_unlock_irqrestore(&dl_b->lock, flags);
rcu_read_unlock_sched();
if (overflow)
return notifier_from_errno(-EBUSY);
}
@@ -5742,7 +5823,7 @@ build_overlap_sched_groups(struct sched_domain *sd, int cpu)
const struct cpumask *span = sched_domain_span(sd);
struct cpumask *covered = sched_domains_tmpmask;
struct sd_data *sdd = sd->private;
struct sched_domain *child;
struct sched_domain *sibling;
int i;
cpumask_clear(covered);
@@ -5753,10 +5834,10 @@ build_overlap_sched_groups(struct sched_domain *sd, int cpu)
if (cpumask_test_cpu(i, covered))
continue;
child = *per_cpu_ptr(sdd->sd, i);
sibling = *per_cpu_ptr(sdd->sd, i);
/* See the comment near build_group_mask(). */
if (!cpumask_test_cpu(i, sched_domain_span(child)))
if (!cpumask_test_cpu(i, sched_domain_span(sibling)))
continue;
sg = kzalloc_node(sizeof(struct sched_group) + cpumask_size(),
@@ -5766,10 +5847,9 @@ build_overlap_sched_groups(struct sched_domain *sd, int cpu)
goto fail;
sg_span = sched_group_cpus(sg);
if (child->child) {
child = child->child;
cpumask_copy(sg_span, sched_domain_span(child));
} else
if (sibling->child)
cpumask_copy(sg_span, sched_domain_span(sibling->child));
else
cpumask_set_cpu(i, sg_span);
cpumask_or(covered, covered, sg_span);
@@ -7120,13 +7200,13 @@ static void normalize_task(struct rq *rq, struct task_struct *p)
.sched_policy = SCHED_NORMAL,
};
int old_prio = p->prio;
int on_rq;
int queued;
on_rq = p->on_rq;
if (on_rq)
queued = task_on_rq_queued(p);
if (queued)
dequeue_task(rq, p, 0);
__setscheduler(rq, p, &attr);
if (on_rq) {
if (queued) {
enqueue_task(rq, p, 0);
resched_curr(rq);
}
@@ -7140,12 +7220,12 @@ void normalize_rt_tasks(void)
unsigned long flags;
struct rq *rq;
read_lock_irqsave(&tasklist_lock, flags);
do_each_thread(g, p) {
read_lock(&tasklist_lock);
for_each_process_thread(g, p) {
/*
* Only normalize user tasks:
*/
if (!p->mm)
if (p->flags & PF_KTHREAD)
continue;
p->se.exec_start = 0;
@@ -7160,21 +7240,16 @@ void normalize_rt_tasks(void)
* Renice negative nice level userspace
* tasks back to 0:
*/
if (task_nice(p) < 0 && p->mm)
if (task_nice(p) < 0)
set_user_nice(p, 0);
continue;
}
raw_spin_lock(&p->pi_lock);
rq = __task_rq_lock(p);
rq = task_rq_lock(p, &flags);
normalize_task(rq, p);
__task_rq_unlock(rq);
raw_spin_unlock(&p->pi_lock);
} while_each_thread(g, p);
read_unlock_irqrestore(&tasklist_lock, flags);
task_rq_unlock(rq, p, &flags);
}
read_unlock(&tasklist_lock);
}
#endif /* CONFIG_MAGIC_SYSRQ */
@@ -7314,19 +7389,19 @@ void sched_offline_group(struct task_group *tg)
void sched_move_task(struct task_struct *tsk)
{
struct task_group *tg;
int on_rq, running;
int queued, running;
unsigned long flags;
struct rq *rq;
rq = task_rq_lock(tsk, &flags);
running = task_current(rq, tsk);
on_rq = tsk->on_rq;
queued = task_on_rq_queued(tsk);
if (on_rq)
if (queued)
dequeue_task(rq, tsk, 0);
if (unlikely(running))
tsk->sched_class->put_prev_task(rq, tsk);
put_prev_task(rq, tsk);
tg = container_of(task_css_check(tsk, cpu_cgrp_id,
lockdep_is_held(&tsk->sighand->siglock)),
@@ -7336,14 +7411,14 @@ void sched_move_task(struct task_struct *tsk)
#ifdef CONFIG_FAIR_GROUP_SCHED
if (tsk->sched_class->task_move_group)
tsk->sched_class->task_move_group(tsk, on_rq);
tsk->sched_class->task_move_group(tsk, queued);
else
#endif
set_task_rq(tsk, task_cpu(tsk));
if (unlikely(running))
tsk->sched_class->set_curr_task(rq);
if (on_rq)
if (queued)
enqueue_task(rq, tsk, 0);
task_rq_unlock(rq, tsk, &flags);
@@ -7361,10 +7436,10 @@ static inline int tg_has_rt_tasks(struct task_group *tg)
{
struct task_struct *g, *p;
do_each_thread(g, p) {
if (rt_task(p) && task_rq(p)->rt.tg == tg)
for_each_process_thread(g, p) {
if (rt_task(p) && task_group(p) == tg)
return 1;
} while_each_thread(g, p);
}
return 0;
}
@@ -7573,6 +7648,7 @@ static int sched_dl_global_constraints(void)
u64 runtime = global_rt_runtime();
u64 period = global_rt_period();
u64 new_bw = to_ratio(period, runtime);
struct dl_bw *dl_b;
int cpu, ret = 0;
unsigned long flags;
@@ -7586,13 +7662,16 @@ static int sched_dl_global_constraints(void)
* solutions is welcome!
*/
for_each_possible_cpu(cpu) {
struct dl_bw *dl_b = dl_bw_of(cpu);
rcu_read_lock_sched();
dl_b = dl_bw_of(cpu);
raw_spin_lock_irqsave(&dl_b->lock, flags);
if (new_bw < dl_b->total_bw)
ret = -EBUSY;
raw_spin_unlock_irqrestore(&dl_b->lock, flags);
rcu_read_unlock_sched();
if (ret)
break;
}
@@ -7603,6 +7682,7 @@ static int sched_dl_global_constraints(void)
static void sched_dl_do_global(void)
{
u64 new_bw = -1;
struct dl_bw *dl_b;
int cpu;
unsigned long flags;
@@ -7616,11 +7696,14 @@ static void sched_dl_do_global(void)
* FIXME: As above...
*/
for_each_possible_cpu(cpu) {
struct dl_bw *dl_b = dl_bw_of(cpu);
rcu_read_lock_sched();
dl_b = dl_bw_of(cpu);
raw_spin_lock_irqsave(&dl_b->lock, flags);
dl_b->bw = new_bw;
raw_spin_unlock_irqrestore(&dl_b->lock, flags);
rcu_read_unlock_sched();
}
}
@@ -8001,7 +8084,7 @@ static int tg_cfs_schedulable_down(struct task_group *tg, void *data)
struct cfs_bandwidth *parent_b = &tg->parent->cfs_bandwidth;
quota = normalize_cfs_quota(tg, d);
parent_quota = parent_b->hierarchal_quota;
parent_quota = parent_b->hierarchical_quota;
/*
* ensure max(child_quota) <= parent_quota, inherit when no
@@ -8012,7 +8095,7 @@ static int tg_cfs_schedulable_down(struct task_group *tg, void *data)
else if (parent_quota != RUNTIME_INF && quota > parent_quota)
return -EINVAL;
}
cfs_b->hierarchal_quota = quota;
cfs_b->hierarchical_quota = quota;
return 0;
}

4
kernel/sched/cpudeadline.c
View File

@@ -107,9 +107,7 @@ int cpudl_find(struct cpudl *cp, struct task_struct *p,
int best_cpu = -1;
const struct sched_dl_entity *dl_se = &p->dl;
if (later_mask && cpumask_and(later_mask, cp->free_cpus,
&p->cpus_allowed) && cpumask_and(later_mask,
later_mask, cpu_active_mask)) {
if (later_mask && cpumask_and(later_mask, later_mask, cp->free_cpus)) {
best_cpu = cpumask_any(later_mask);
goto out;
} else if (cpumask_test_cpu(cpudl_maximum(cp), &p->cpus_allowed) &&

64
kernel/sched/cputime.c
View File

@@ -288,24 +288,29 @@ void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times)
struct signal_struct *sig = tsk->signal;
cputime_t utime, stime;
struct task_struct *t;
times->utime = sig->utime;
times->stime = sig->stime;
times->sum_exec_runtime = sig->sum_sched_runtime;
unsigned int seq, nextseq;
unsigned long flags;
rcu_read_lock();
/* make sure we can trust tsk->thread_group list */
if (!likely(pid_alive(tsk)))
goto out;
t = tsk;
/* Attempt a lockless read on the first round. */
nextseq = 0;
do {
task_cputime(t, &utime, &stime);
times->utime += utime;
times->stime += stime;
times->sum_exec_runtime += task_sched_runtime(t);
} while_each_thread(tsk, t);
out:
seq = nextseq;
flags = read_seqbegin_or_lock_irqsave(&sig->stats_lock, &seq);
times->utime = sig->utime;
times->stime = sig->stime;
times->sum_exec_runtime = sig->sum_sched_runtime;
for_each_thread(tsk, t) {
task_cputime(t, &utime, &stime);
times->utime += utime;
times->stime += stime;
times->sum_exec_runtime += task_sched_runtime(t);
}
/* If lockless access failed, take the lock. */
nextseq = 1;
} while (need_seqretry(&sig->stats_lock, seq));
done_seqretry_irqrestore(&sig->stats_lock, seq, flags);
rcu_read_unlock();
}
@@ -549,6 +554,23 @@ drop_precision:
return (__force cputime_t) scaled;
}
/*
* Atomically advance counter to the new value. Interrupts, vcpu
* scheduling, and scaling inaccuracies can cause cputime_advance
* to be occasionally called with a new value smaller than counter.
* Let's enforce atomicity.
*
* Normally a caller will only go through this loop once, or not
* at all in case a previous caller updated counter the same jiffy.
*/
static void cputime_advance(cputime_t *counter, cputime_t new)
{
cputime_t old;
while (new > (old = ACCESS_ONCE(*counter)))
cmpxchg_cputime(counter, old, new);
}
/*
* Adjust tick based cputime random precision against scheduler
* runtime accounting.
@@ -594,13 +616,8 @@ static void cputime_adjust(struct task_cputime *curr,
utime = rtime - stime;
}
/*
* If the tick based count grows faster than the scheduler one,
* the result of the scaling may go backward.
* Let's enforce monotonicity.
*/
prev->stime = max(prev->stime, stime);
prev->utime = max(prev->utime, utime);
cputime_advance(&prev->stime, stime);
cputime_advance(&prev->utime, utime);
out:
*ut = prev->utime;
@@ -617,9 +634,6 @@ void task_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st)
cputime_adjust(&cputime, &p->prev_cputime, ut, st);
}
/*
* Must be called with siglock held.
*/
void thread_group_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st)
{
struct task_cputime cputime;

33
kernel/sched/deadline.c
View File

@@ -530,7 +530,7 @@ again:
update_rq_clock(rq);
dl_se->dl_throttled = 0;
dl_se->dl_yielded = 0;
if (p->on_rq) {
if (task_on_rq_queued(p)) {
enqueue_task_dl(rq, p, ENQUEUE_REPLENISH);
if (task_has_dl_policy(rq->curr))
check_preempt_curr_dl(rq, p, 0);
@@ -997,10 +997,7 @@ static void check_preempt_curr_dl(struct rq *rq, struct task_struct *p,
#ifdef CONFIG_SCHED_HRTICK
static void start_hrtick_dl(struct rq *rq, struct task_struct *p)
{
s64 delta = p->dl.dl_runtime - p->dl.runtime;
if (delta > 10000)
hrtick_start(rq, p->dl.runtime);
hrtick_start(rq, p->dl.runtime);
}
#endif
@@ -1030,7 +1027,7 @@ struct task_struct *pick_next_task_dl(struct rq *rq, struct task_struct *prev)
* means a stop task can slip in, in which case we need to
* re-start task selection.
*/
if (rq->stop && rq->stop->on_rq)
if (rq->stop && task_on_rq_queued(rq->stop))
return RETRY_TASK;
}
@@ -1124,10 +1121,8 @@ static void set_curr_task_dl(struct rq *rq)
static int pick_dl_task(struct rq *rq, struct task_struct *p, int cpu)
{
if (!task_running(rq, p) &&
(cpu < 0 || cpumask_test_cpu(cpu, &p->cpus_allowed)) &&
(p->nr_cpus_allowed > 1))
cpumask_test_cpu(cpu, tsk_cpus_allowed(p)))
return 1;
return 0;
}
@@ -1169,6 +1164,13 @@ static int find_later_rq(struct task_struct *task)
if (task->nr_cpus_allowed == 1)
return -1;
/*
* We have to consider system topology and task affinity
* first, then we can look for a suitable cpu.
*/
cpumask_copy(later_mask, task_rq(task)->rd->span);
cpumask_and(later_mask, later_mask, cpu_active_mask);
cpumask_and(later_mask, later_mask, &task->cpus_allowed);
best_cpu = cpudl_find(&task_rq(task)->rd->cpudl,
task, later_mask);
if (best_cpu == -1)
@@ -1257,7 +1259,8 @@ static struct rq *find_lock_later_rq(struct task_struct *task, struct rq *rq)
if (unlikely(task_rq(task) != rq ||
!cpumask_test_cpu(later_rq->cpu,
&task->cpus_allowed) ||
task_running(rq, task) || !task->on_rq)) {
task_running(rq, task) ||
!task_on_rq_queued(task))) {
double_unlock_balance(rq, later_rq);
later_rq = NULL;
break;
@@ -1296,7 +1299,7 @@ static struct task_struct *pick_next_pushable_dl_task(struct rq *rq)
BUG_ON(task_current(rq, p));
BUG_ON(p->nr_cpus_allowed <= 1);
BUG_ON(!p->on_rq);
BUG_ON(!task_on_rq_queued(p));
BUG_ON(!dl_task(p));
return p;
@@ -1443,7 +1446,7 @@ static int pull_dl_task(struct rq *this_rq)
dl_time_before(p->dl.deadline,
this_rq->dl.earliest_dl.curr))) {
WARN_ON(p == src_rq->curr);
WARN_ON(!p->on_rq);
WARN_ON(!task_on_rq_queued(p));
/*
* Then we pull iff p has actually an earlier
@@ -1569,6 +1572,8 @@ static void switched_from_dl(struct rq *rq, struct task_struct *p)
if (hrtimer_active(&p->dl.dl_timer) && !dl_policy(p->policy))
hrtimer_try_to_cancel(&p->dl.dl_timer);
__dl_clear_params(p);
#ifdef CONFIG_SMP
/*
* Since this might be the only -deadline task on the rq,
@@ -1596,7 +1601,7 @@ static void switched_to_dl(struct rq *rq, struct task_struct *p)
if (unlikely(p->dl.dl_throttled))
return;
if (p->on_rq && rq->curr != p) {
if (task_on_rq_queued(p) && rq->curr != p) {
#ifdef CONFIG_SMP
if (rq->dl.overloaded && push_dl_task(rq) && rq != task_rq(p))
/* Only reschedule if pushing failed */
@@ -1614,7 +1619,7 @@ static void switched_to_dl(struct rq *rq, struct task_struct *p)
static void prio_changed_dl(struct rq *rq, struct task_struct *p,
int oldprio)
{
if (p->on_rq || rq->curr == p) {
if (task_on_rq_queued(p) || rq->curr == p) {
#ifdef CONFIG_SMP
/*
* This might be too much, but unfortunately

13
kernel/sched/debug.c
View File

@@ -150,7 +150,6 @@ print_task(struct seq_file *m, struct rq *rq, struct task_struct *p)
static void print_rq(struct seq_file *m, struct rq *rq, int rq_cpu)
{
struct task_struct *g, *p;
unsigned long flags;
SEQ_printf(m,
"\nrunnable tasks:\n"
@@ -159,16 +158,14 @@ static void print_rq(struct seq_file *m, struct rq *rq, int rq_cpu)
"------------------------------------------------------"
"----------------------------------------------------\n");
read_lock_irqsave(&tasklist_lock, flags);
do_each_thread(g, p) {
rcu_read_lock();
for_each_process_thread(g, p) {
if (task_cpu(p) != rq_cpu)
continue;
print_task(m, rq, p);
} while_each_thread(g, p);
read_unlock_irqrestore(&tasklist_lock, flags);
}
rcu_read_unlock();
}
void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
@@ -333,9 +330,7 @@ do { \
print_cfs_stats(m, cpu);
print_rt_stats(m, cpu);
rcu_read_lock();
print_rq(m, rq, cpu);
rcu_read_unlock();
spin_unlock_irqrestore(&sched_debug_lock, flags);
SEQ_printf(m, "\n");
}

483
kernel/sched/fair.c
View File

@@ -23,6 +23,7 @@
#include <linux/latencytop.h>
#include <linux/sched.h>
#include <linux/cpumask.h>
#include <linux/cpuidle.h>
#include <linux/slab.h>
#include <linux/profile.h>
#include <linux/interrupt.h>
@@ -665,6 +666,7 @@ static u64 sched_vslice(struct cfs_rq *cfs_rq, struct sched_entity *se)
}
#ifdef CONFIG_SMP
static int select_idle_sibling(struct task_struct *p, int cpu);
static unsigned long task_h_load(struct task_struct *p);
static inline void __update_task_entity_contrib(struct sched_entity *se);
@@ -1038,7 +1040,8 @@ struct numa_stats {
*/
static void update_numa_stats(struct numa_stats *ns, int nid)
{
int cpu, cpus = 0;
int smt, cpu, cpus = 0;
unsigned long capacity;
memset(ns, 0, sizeof(*ns));
for_each_cpu(cpu, cpumask_of_node(nid)) {
@@ -1062,8 +1065,12 @@ static void update_numa_stats(struct numa_stats *ns, int nid)
if (!cpus)
return;
ns->task_capacity =
DIV_ROUND_CLOSEST(ns->compute_capacity, SCHED_CAPACITY_SCALE);
/* smt := ceil(cpus / capacity), assumes: 1 < smt_power < 2 */
smt = DIV_ROUND_UP(SCHED_CAPACITY_SCALE * cpus, ns->compute_capacity);
capacity = cpus / smt; /* cores */
ns->task_capacity = min_t(unsigned, capacity,
DIV_ROUND_CLOSEST(ns->compute_capacity, SCHED_CAPACITY_SCALE));
ns->has_free_capacity = (ns->nr_running < ns->task_capacity);
}
@@ -1206,7 +1213,7 @@ static void task_numa_compare(struct task_numa_env *env,
if (!cur) {
/* Is there capacity at our destination? */
if (env->src_stats.has_free_capacity &&
if (env->src_stats.nr_running <= env->src_stats.task_capacity &&
!env->dst_stats.has_free_capacity)
goto unlock;
@@ -1252,6 +1259,13 @@ balance:
if (load_too_imbalanced(src_load, dst_load, env))
goto unlock;
/*
* One idle CPU per node is evaluated for a task numa move.
* Call select_idle_sibling to maybe find a better one.
*/
if (!cur)
env->dst_cpu = select_idle_sibling(env->p, env->dst_cpu);
assign:
task_numa_assign(env, cur, imp);
unlock:
@@ -1775,7 +1789,7 @@ void task_numa_free(struct task_struct *p)
list_del(&p->numa_entry);
grp->nr_tasks--;
spin_unlock_irqrestore(&grp->lock, flags);
rcu_assign_pointer(p->numa_group, NULL);
RCU_INIT_POINTER(p->numa_group, NULL);
put_numa_group(grp);
}
@@ -1804,10 +1818,6 @@ void task_numa_fault(int last_cpupid, int mem_node, int pages, int flags)
if (!p->mm)
return;
/* Do not worry about placement if exiting */
if (p->state == TASK_DEAD)
return;
/* Allocate buffer to track faults on a per-node basis */
if (unlikely(!p->numa_faults_memory)) {
int size = sizeof(*p->numa_faults_memory) *
@@ -2211,8 +2221,8 @@ static __always_inline u64 decay_load(u64 val, u64 n)
/*
* As y^PERIOD = 1/2, we can combine
* y^n = 1/2^(n/PERIOD) * k^(n%PERIOD)
* With a look-up table which covers k^n (n<PERIOD)
* y^n = 1/2^(n/PERIOD) * y^(n%PERIOD)
* With a look-up table which covers y^n (n<PERIOD)
*
* To achieve constant time decay_load.
*/
@@ -2377,6 +2387,9 @@ static inline void __update_cfs_rq_tg_load_contrib(struct cfs_rq *cfs_rq,
tg_contrib = cfs_rq->runnable_load_avg + cfs_rq->blocked_load_avg;
tg_contrib -= cfs_rq->tg_load_contrib;
if (!tg_contrib)
return;
if (force_update || abs(tg_contrib) > cfs_rq->tg_load_contrib / 8) {
atomic_long_add(tg_contrib, &tg->load_avg);
cfs_rq->tg_load_contrib += tg_contrib;
@@ -3892,14 +3905,6 @@ static void hrtick_start_fair(struct rq *rq, struct task_struct *p)
resched_curr(rq);
return;
}
/*
* Don't schedule slices shorter than 10000ns, that just
* doesn't make sense. Rely on vruntime for fairness.
*/
if (rq->curr != p)
delta = max_t(s64, 10000LL, delta);
hrtick_start(rq, delta);
}
}
@@ -4087,7 +4092,7 @@ static unsigned long capacity_of(int cpu)
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);
unsigned long nr_running = ACCESS_ONCE(rq->cfs.h_nr_running);
unsigned long load_avg = rq->cfs.runnable_load_avg;
if (nr_running)
@@ -4276,8 +4281,8 @@ static int wake_wide(struct task_struct *p)
static int wake_affine(struct sched_domain *sd, struct task_struct *p, int sync)
{
s64 this_load, load;
s64 this_eff_load, prev_eff_load;
int idx, this_cpu, prev_cpu;
unsigned long tl_per_task;
struct task_group *tg;
unsigned long weight;
int balanced;
@@ -4320,47 +4325,30 @@ static int wake_affine(struct sched_domain *sd, struct task_struct *p, int sync)
* Otherwise check if either cpus are near enough in load to allow this
* task to be woken on this_cpu.
*/
if (this_load > 0) {
s64 this_eff_load, prev_eff_load;
this_eff_load = 100;
this_eff_load *= capacity_of(prev_cpu);
this_eff_load = 100;
this_eff_load *= capacity_of(prev_cpu);
prev_eff_load = 100 + (sd->imbalance_pct - 100) / 2;
prev_eff_load *= capacity_of(this_cpu);
if (this_load > 0) {
this_eff_load *= this_load +
effective_load(tg, this_cpu, weight, weight);
prev_eff_load = 100 + (sd->imbalance_pct - 100) / 2;
prev_eff_load *= capacity_of(this_cpu);
prev_eff_load *= load + effective_load(tg, prev_cpu, 0, weight);
}
balanced = this_eff_load <= prev_eff_load;
} else
balanced = true;
/*
* If the currently running task will sleep within
* a reasonable amount of time then attract this newly
* woken task:
*/
if (sync && balanced)
return 1;
balanced = this_eff_load <= prev_eff_load;
schedstat_inc(p, se.statistics.nr_wakeups_affine_attempts);
tl_per_task = cpu_avg_load_per_task(this_cpu);
if (balanced ||
(this_load <= load &&
this_load + target_load(prev_cpu, idx) <= tl_per_task)) {
/*
* This domain has SD_WAKE_AFFINE and
* p is cache cold in this domain, and
* there is no bad imbalance.
*/
schedstat_inc(sd, ttwu_move_affine);
schedstat_inc(p, se.statistics.nr_wakeups_affine);
if (!balanced)
return 0;
return 1;
}
return 0;
schedstat_inc(sd, ttwu_move_affine);
schedstat_inc(p, se.statistics.nr_wakeups_affine);
return 1;
}
/*
@@ -4428,20 +4416,46 @@ static int
find_idlest_cpu(struct sched_group *group, struct task_struct *p, int this_cpu)
{
unsigned long load, min_load = ULONG_MAX;
int idlest = -1;
unsigned int min_exit_latency = UINT_MAX;
u64 latest_idle_timestamp = 0;
int least_loaded_cpu = this_cpu;
int shallowest_idle_cpu = -1;
int i;
/* Traverse only the allowed CPUs */
for_each_cpu_and(i, sched_group_cpus(group), tsk_cpus_allowed(p)) {
load = weighted_cpuload(i);
if (load < min_load || (load == min_load && i == this_cpu)) {
min_load = load;
idlest = i;
if (idle_cpu(i)) {
struct rq *rq = cpu_rq(i);
struct cpuidle_state *idle = idle_get_state(rq);
if (idle && idle->exit_latency < min_exit_latency) {
/*
* We give priority to a CPU whose idle state
* has the smallest exit latency irrespective
* of any idle timestamp.
*/
min_exit_latency = idle->exit_latency;
latest_idle_timestamp = rq->idle_stamp;
shallowest_idle_cpu = i;
} else if ((!idle || idle->exit_latency == min_exit_latency) &&
rq->idle_stamp > latest_idle_timestamp) {
/*
* If equal or no active idle state, then
* the most recently idled CPU might have
* a warmer cache.
*/
latest_idle_timestamp = rq->idle_stamp;
shallowest_idle_cpu = i;
}
} else {
load = weighted_cpuload(i);
if (load < min_load || (load == min_load && i == this_cpu)) {
min_load = load;
least_loaded_cpu = i;
}
}
}
return idlest;
return shallowest_idle_cpu != -1 ? shallowest_idle_cpu : least_loaded_cpu;
}
/*
@@ -4513,11 +4527,8 @@ select_task_rq_fair(struct task_struct *p, int prev_cpu, int sd_flag, int wake_f
if (p->nr_cpus_allowed == 1)
return prev_cpu;
if (sd_flag & SD_BALANCE_WAKE) {
if (cpumask_test_cpu(cpu, tsk_cpus_allowed(p)))
want_affine = 1;
new_cpu = prev_cpu;
}
if (sd_flag & SD_BALANCE_WAKE)
want_affine = cpumask_test_cpu(cpu, tsk_cpus_allowed(p));
rcu_read_lock();
for_each_domain(cpu, tmp) {
@@ -4704,7 +4715,7 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p, int wake_
return;
/*
* This is possible from callers such as move_task(), in which we
* This is possible from callers such as attach_tasks(), in which we
* unconditionally check_prempt_curr() after an enqueue (which may have
* lead to a throttle). This both saves work and prevents false
* next-buddy nomination below.
@@ -5112,20 +5123,9 @@ struct lb_env {
unsigned int loop_max;
enum fbq_type fbq_type;
struct list_head tasks;
};
/*
* move_task - move a task from one runqueue to another runqueue.
* Both runqueues must be locked.
*/
static void move_task(struct task_struct *p, struct lb_env *env)
{
deactivate_task(env->src_rq, p, 0);
set_task_cpu(p, env->dst_cpu);
activate_task(env->dst_rq, p, 0);
check_preempt_curr(env->dst_rq, p, 0);
}
/*
* Is this task likely cache-hot:
*/
@@ -5133,6 +5133,8 @@ static int task_hot(struct task_struct *p, struct lb_env *env)
{
s64 delta;
lockdep_assert_held(&env->src_rq->lock);
if (p->sched_class != &fair_sched_class)
return 0;
@@ -5252,6 +5254,9 @@ static
int can_migrate_task(struct task_struct *p, struct lb_env *env)
{
int tsk_cache_hot = 0;
lockdep_assert_held(&env->src_rq->lock);
/*
* We do not migrate tasks that are:
* 1) throttled_lb_pair, or
@@ -5310,24 +5315,12 @@ int can_migrate_task(struct task_struct *p, struct lb_env *env)
if (!tsk_cache_hot)
tsk_cache_hot = migrate_degrades_locality(p, env);
if (migrate_improves_locality(p, env)) {
#ifdef CONFIG_SCHEDSTATS
if (migrate_improves_locality(p, env) || !tsk_cache_hot ||
env->sd->nr_balance_failed > env->sd->cache_nice_tries) {
if (tsk_cache_hot) {
schedstat_inc(env->sd, lb_hot_gained[env->idle]);
schedstat_inc(p, se.statistics.nr_forced_migrations);
}
#endif
return 1;
}
if (!tsk_cache_hot ||
env->sd->nr_balance_failed > env->sd->cache_nice_tries) {
if (tsk_cache_hot) {
schedstat_inc(env->sd, lb_hot_gained[env->idle]);
schedstat_inc(p, se.statistics.nr_forced_migrations);
}
return 1;
}
@@ -5336,47 +5329,63 @@ int can_migrate_task(struct task_struct *p, struct lb_env *env)
}
/*
* move_one_task tries to move exactly one task from busiest to this_rq, as
* part of active balancing operations within "domain".
* Returns 1 if successful and 0 otherwise.
*
* Called with both runqueues locked.
* detach_task() -- detach the task for the migration specified in env
*/
static int move_one_task(struct lb_env *env)
static void detach_task(struct task_struct *p, struct lb_env *env)
{
lockdep_assert_held(&env->src_rq->lock);
deactivate_task(env->src_rq, p, 0);
p->on_rq = TASK_ON_RQ_MIGRATING;
set_task_cpu(p, env->dst_cpu);
}
/*
* detach_one_task() -- tries to dequeue exactly one task from env->src_rq, as
* part of active balancing operations within "domain".
*
* Returns a task if successful and NULL otherwise.
*/
static struct task_struct *detach_one_task(struct lb_env *env)
{
struct task_struct *p, *n;
lockdep_assert_held(&env->src_rq->lock);
list_for_each_entry_safe(p, n, &env->src_rq->cfs_tasks, se.group_node) {
if (!can_migrate_task(p, env))
continue;
move_task(p, env);
detach_task(p, env);
/*
* Right now, this is only the second place move_task()
* is called, so we can safely collect move_task()
* stats here rather than inside move_task().
* Right now, this is only the second place where
* lb_gained[env->idle] is updated (other is detach_tasks)
* so we can safely collect stats here rather than
* inside detach_tasks().
*/
schedstat_inc(env->sd, lb_gained[env->idle]);
return 1;
return p;
}
return 0;
return NULL;
}
static const unsigned int sched_nr_migrate_break = 32;
/*
* move_tasks tries to move up to imbalance weighted load from busiest to
* this_rq, as part of a balancing operation within domain "sd".
* Returns 1 if successful and 0 otherwise.
* detach_tasks() -- tries to detach up to imbalance weighted load from
* busiest_rq, as part of a balancing operation within domain "sd".
*
* Called with both runqueues locked.
* Returns number of detached tasks if successful and 0 otherwise.
*/
static int move_tasks(struct lb_env *env)
static int detach_tasks(struct lb_env *env)
{
struct list_head *tasks = &env->src_rq->cfs_tasks;
struct task_struct *p;
unsigned long load;
int pulled = 0;
int detached = 0;
lockdep_assert_held(&env->src_rq->lock);
if (env->imbalance <= 0)
return 0;
@@ -5407,14 +5416,16 @@ static int move_tasks(struct lb_env *env)
if ((load / 2) > env->imbalance)
goto next;
move_task(p, env);
pulled++;
detach_task(p, env);
list_add(&p->se.group_node, &env->tasks);
detached++;
env->imbalance -= load;
#ifdef CONFIG_PREEMPT
/*
* NEWIDLE balancing is a source of latency, so preemptible
* kernels will stop after the first task is pulled to minimize
* kernels will stop after the first task is detached to minimize
* the critical section.
*/
if (env->idle == CPU_NEWLY_IDLE)
@@ -5434,13 +5445,58 @@ next:
}
/*
* Right now, this is one of only two places move_task() is called,
* so we can safely collect move_task() stats here rather than
* inside move_task().
* Right now, this is one of only two places we collect this stat
* so we can safely collect detach_one_task() stats here rather
* than inside detach_one_task().
*/
schedstat_add(env->sd, lb_gained[env->idle], pulled);
schedstat_add(env->sd, lb_gained[env->idle], detached);
return pulled;
return detached;
}
/*
* attach_task() -- attach the task detached by detach_task() to its new rq.
*/
static void attach_task(struct rq *rq, struct task_struct *p)
{
lockdep_assert_held(&rq->lock);
BUG_ON(task_rq(p) != rq);
p->on_rq = TASK_ON_RQ_QUEUED;
activate_task(rq, p, 0);
check_preempt_curr(rq, p, 0);
}
/*
* attach_one_task() -- attaches the task returned from detach_one_task() to
* its new rq.
*/
static void attach_one_task(struct rq *rq, struct task_struct *p)
{
raw_spin_lock(&rq->lock);
attach_task(rq, p);
raw_spin_unlock(&rq->lock);
}
/*
* attach_tasks() -- attaches all tasks detached by detach_tasks() to their
* new rq.
*/
static void attach_tasks(struct lb_env *env)
{
struct list_head *tasks = &env->tasks;
struct task_struct *p;
raw_spin_lock(&env->dst_rq->lock);
while (!list_empty(tasks)) {
p = list_first_entry(tasks, struct task_struct, se.group_node);
list_del_init(&p->se.group_node);
attach_task(env->dst_rq, p);
}
raw_spin_unlock(&env->dst_rq->lock);
}
#ifdef CONFIG_FAIR_GROUP_SCHED
@@ -5559,6 +5615,13 @@ static unsigned long task_h_load(struct task_struct *p)
#endif
/********** Helpers for find_busiest_group ************************/
enum group_type {
group_other = 0,
group_imbalanced,
group_overloaded,
};
/*
* sg_lb_stats - stats of a sched_group required for load_balancing
*/
@@ -5572,7 +5635,7 @@ struct sg_lb_stats {
unsigned int group_capacity_factor;
unsigned int idle_cpus;
unsigned int group_weight;
int group_imb; /* Is there an imbalance in the group ? */
enum group_type group_type;
int group_has_free_capacity;
#ifdef CONFIG_NUMA_BALANCING
unsigned int nr_numa_running;
@@ -5610,6 +5673,8 @@ static inline void init_sd_lb_stats(struct sd_lb_stats *sds)
.total_capacity = 0UL,
.busiest_stat = {
.avg_load = 0UL,
.sum_nr_running = 0,
.group_type = group_other,
},
};
}
@@ -5652,19 +5717,17 @@ unsigned long __weak arch_scale_freq_capacity(struct sched_domain *sd, int cpu)
return default_scale_capacity(sd, cpu);
}
static unsigned long default_scale_smt_capacity(struct sched_domain *sd, int cpu)
static unsigned long default_scale_cpu_capacity(struct sched_domain *sd, int cpu)
{
unsigned long weight = sd->span_weight;
unsigned long smt_gain = sd->smt_gain;
if ((sd->flags & SD_SHARE_CPUCAPACITY) && (sd->span_weight > 1))
return sd->smt_gain / sd->span_weight;
smt_gain /= weight;
return smt_gain;
return SCHED_CAPACITY_SCALE;
}
unsigned long __weak arch_scale_smt_capacity(struct sched_domain *sd, int cpu)
unsigned long __weak arch_scale_cpu_capacity(struct sched_domain *sd, int cpu)
{
return default_scale_smt_capacity(sd, cpu);
return default_scale_cpu_capacity(sd, cpu);
}
static unsigned long scale_rt_capacity(int cpu)
@@ -5703,18 +5766,15 @@ static unsigned long scale_rt_capacity(int cpu)
static void update_cpu_capacity(struct sched_domain *sd, int cpu)
{
unsigned long weight = sd->span_weight;
unsigned long capacity = SCHED_CAPACITY_SCALE;
struct sched_group *sdg = sd->groups;
if ((sd->flags & SD_SHARE_CPUCAPACITY) && weight > 1) {
if (sched_feat(ARCH_CAPACITY))
capacity *= arch_scale_smt_capacity(sd, cpu);
else
capacity *= default_scale_smt_capacity(sd, cpu);
if (sched_feat(ARCH_CAPACITY))
capacity *= arch_scale_cpu_capacity(sd, cpu);
else
capacity *= default_scale_cpu_capacity(sd, cpu);
capacity >>= SCHED_CAPACITY_SHIFT;
}
capacity >>= SCHED_CAPACITY_SHIFT;
sdg->sgc->capacity_orig = capacity;
@@ -5891,6 +5951,18 @@ static inline int sg_capacity_factor(struct lb_env *env, struct sched_group *gro
return capacity_factor;
}
static enum group_type
group_classify(struct sched_group *group, struct sg_lb_stats *sgs)
{
if (sgs->sum_nr_running > sgs->group_capacity_factor)
return group_overloaded;
if (sg_imbalanced(group))
return group_imbalanced;
return group_other;
}
/**
* update_sg_lb_stats - Update sched_group's statistics for load balancing.
* @env: The load balancing environment.
@@ -5920,7 +5992,7 @@ static inline void update_sg_lb_stats(struct lb_env *env,
load = source_load(i, load_idx);
sgs->group_load += load;
sgs->sum_nr_running += rq->nr_running;
sgs->sum_nr_running += rq->cfs.h_nr_running;
if (rq->nr_running > 1)
*overload = true;
@@ -5942,9 +6014,8 @@ static inline void update_sg_lb_stats(struct lb_env *env,
sgs->load_per_task = sgs->sum_weighted_load / sgs->sum_nr_running;
sgs->group_weight = group->group_weight;
sgs->group_imb = sg_imbalanced(group);
sgs->group_capacity_factor = sg_capacity_factor(env, group);
sgs->group_type = group_classify(group, sgs);
if (sgs->group_capacity_factor > sgs->sum_nr_running)
sgs->group_has_free_capacity = 1;
@@ -5968,13 +6039,19 @@ static bool update_sd_pick_busiest(struct lb_env *env,
struct sched_group *sg,
struct sg_lb_stats *sgs)
{
if (sgs->avg_load <= sds->busiest_stat.avg_load)
return false;
struct sg_lb_stats *busiest = &sds->busiest_stat;
if (sgs->sum_nr_running > sgs->group_capacity_factor)
if (sgs->group_type > busiest->group_type)
return true;
if (sgs->group_imb)
if (sgs->group_type < busiest->group_type)
return false;
if (sgs->avg_load <= busiest->avg_load)
return false;
/* This is the busiest node in its class. */
if (!(env->sd->flags & SD_ASYM_PACKING))
return true;
/*
@@ -5982,8 +6059,7 @@ static bool update_sd_pick_busiest(struct lb_env *env,
* numbered CPUs in the group, therefore mark all groups
* higher than ourself as busy.
*/
if ((env->sd->flags & SD_ASYM_PACKING) && sgs->sum_nr_running &&
env->dst_cpu < group_first_cpu(sg)) {
if (sgs->sum_nr_running && env->dst_cpu < group_first_cpu(sg)) {
if (!sds->busiest)
return true;
@@ -6228,7 +6304,7 @@ static inline void calculate_imbalance(struct lb_env *env, struct sd_lb_stats *s
local = &sds->local_stat;
busiest = &sds->busiest_stat;
if (busiest->group_imb) {
if (busiest->group_type == group_imbalanced) {
/*
* In the group_imb case we cannot rely on group-wide averages
* to ensure cpu-load equilibrium, look at wider averages. XXX
@@ -6248,12 +6324,11 @@ static inline void calculate_imbalance(struct lb_env *env, struct sd_lb_stats *s
return fix_small_imbalance(env, sds);
}
if (!busiest->group_imb) {
/*
* Don't want to pull so many tasks that a group would go idle.
* Except of course for the group_imb case, since then we might
* have to drop below capacity to reach cpu-load equilibrium.
*/
/*
* If there aren't any idle cpus, avoid creating some.
*/
if (busiest->group_type == group_overloaded &&
local->group_type == group_overloaded) {
load_above_capacity =
(busiest->sum_nr_running - busiest->group_capacity_factor);
@@ -6337,7 +6412,7 @@ static struct sched_group *find_busiest_group(struct lb_env *env)
* work because they assume all things are equal, which typically
* isn't true due to cpus_allowed constraints and the like.
*/
if (busiest->group_imb)
if (busiest->group_type == group_imbalanced)
goto force_balance;
/* SD_BALANCE_NEWIDLE trumps SMP nice when underutilized */
@@ -6346,7 +6421,7 @@ static struct sched_group *find_busiest_group(struct lb_env *env)
goto force_balance;
/*
* If the local group is more busy than the selected busiest group
* If the local group is busier than the selected busiest group
* don't try and pull any tasks.
*/
if (local->avg_load >= busiest->avg_load)
@@ -6361,13 +6436,14 @@ static struct sched_group *find_busiest_group(struct lb_env *env)
if (env->idle == CPU_IDLE) {
/*
* This cpu is idle. If the busiest group load doesn't
* have more tasks than the number of available cpu's and
* there is no imbalance between this and busiest group
* wrt to idle cpu's, it is balanced.
* This cpu is idle. If the busiest group is not overloaded
* and there is no imbalance between this and busiest group
* wrt idle cpus, it is balanced. The imbalance becomes
* significant if the diff is greater than 1 otherwise we
* might end up to just move the imbalance on another group
*/
if ((local->idle_cpus < busiest->idle_cpus) &&
busiest->sum_nr_running <= busiest->group_weight)
if ((busiest->group_type != group_overloaded) &&
(local->idle_cpus <= (busiest->idle_cpus + 1)))
goto out_balanced;
} else {
/*
@@ -6550,6 +6626,7 @@ static int load_balance(int this_cpu, struct rq *this_rq,
.loop_break = sched_nr_migrate_break,
.cpus = cpus,
.fbq_type = all,
.tasks = LIST_HEAD_INIT(env.tasks),
};
/*
@@ -6599,23 +6676,30 @@ redo:
env.loop_max = min(sysctl_sched_nr_migrate, busiest->nr_running);
more_balance:
local_irq_save(flags);
double_rq_lock(env.dst_rq, busiest);
raw_spin_lock_irqsave(&busiest->lock, flags);
/*
* cur_ld_moved - load moved in current iteration
* ld_moved - cumulative load moved across iterations
*/
cur_ld_moved = move_tasks(&env);
ld_moved += cur_ld_moved;
double_rq_unlock(env.dst_rq, busiest);
local_irq_restore(flags);
cur_ld_moved = detach_tasks(&env);
/*
* some other cpu did the load balance for us.
* We've detached some tasks from busiest_rq. Every
* task is masked "TASK_ON_RQ_MIGRATING", so we can safely
* unlock busiest->lock, and we are able to be sure
* that nobody can manipulate the tasks in parallel.
* See task_rq_lock() family for the details.
*/
if (cur_ld_moved && env.dst_cpu != smp_processor_id())
resched_cpu(env.dst_cpu);
raw_spin_unlock(&busiest->lock);
if (cur_ld_moved) {
attach_tasks(&env);
ld_moved += cur_ld_moved;
}
local_irq_restore(flags);
if (env.flags & LBF_NEED_BREAK) {
env.flags &= ~LBF_NEED_BREAK;
@@ -6665,10 +6749,8 @@ more_balance:
if (sd_parent) {
int *group_imbalance = &sd_parent->groups->sgc->imbalance;
if ((env.flags & LBF_SOME_PINNED) && env.imbalance > 0) {
if ((env.flags & LBF_SOME_PINNED) && env.imbalance > 0)
*group_imbalance = 1;
} else if (*group_imbalance)
*group_imbalance = 0;
}
/* All tasks on this runqueue were pinned by CPU affinity */
@@ -6679,7 +6761,7 @@ more_balance:
env.loop_break = sched_nr_migrate_break;
goto redo;
}
goto out_balanced;
goto out_all_pinned;
}
}
@@ -6744,7 +6826,7 @@ more_balance:
* If we've begun active balancing, start to back off. This
* case may not be covered by the all_pinned logic if there
* is only 1 task on the busy runqueue (because we don't call
* move_tasks).
* detach_tasks).
*/
if (sd->balance_interval < sd->max_interval)
sd->balance_interval *= 2;
@@ -6753,6 +6835,23 @@ more_balance:
goto out;
out_balanced:
/*
* We reach balance although we may have faced some affinity
* constraints. Clear the imbalance flag if it was set.
*/
if (sd_parent) {
int *group_imbalance = &sd_parent->groups->sgc->imbalance;
if (*group_imbalance)
*group_imbalance = 0;
}
out_all_pinned:
/*
* We reach balance because all tasks are pinned at this level so
* we can't migrate them. Let the imbalance flag set so parent level
* can try to migrate them.
*/
schedstat_inc(sd, lb_balanced[idle]);
sd->nr_balance_failed = 0;
@@ -6914,6 +7013,7 @@ static int active_load_balance_cpu_stop(void *data)
int target_cpu = busiest_rq->push_cpu;
struct rq *target_rq = cpu_rq(target_cpu);
struct sched_domain *sd;
struct task_struct *p = NULL;
raw_spin_lock_irq(&busiest_rq->lock);
@@ -6933,9 +7033,6 @@ static int active_load_balance_cpu_stop(void *data)
*/
BUG_ON(busiest_rq == target_rq);
/* move a task from busiest_rq to target_rq */
double_lock_balance(busiest_rq, target_rq);
/* Search for an sd spanning us and the target CPU. */
rcu_read_lock();
for_each_domain(target_cpu, sd) {
@@ -6956,16 +7053,22 @@ static int active_load_balance_cpu_stop(void *data)
schedstat_inc(sd, alb_count);
if (move_one_task(&env))
p = detach_one_task(&env);
if (p)
schedstat_inc(sd, alb_pushed);
else
schedstat_inc(sd, alb_failed);
}
rcu_read_unlock();
double_unlock_balance(busiest_rq, target_rq);
out_unlock:
busiest_rq->active_balance = 0;
raw_spin_unlock_irq(&busiest_rq->lock);
raw_spin_unlock(&busiest_rq->lock);
if (p)
attach_one_task(target_rq, p);
local_irq_enable();
return 0;
}
@@ -7465,7 +7568,7 @@ static void task_fork_fair(struct task_struct *p)
static void
prio_changed_fair(struct rq *rq, struct task_struct *p, int oldprio)
{
if (!p->se.on_rq)
if (!task_on_rq_queued(p))
return;
/*
@@ -7490,11 +7593,11 @@ static void switched_from_fair(struct rq *rq, struct task_struct *p)
* switched back to the fair class the enqueue_entity(.flags=0) will
* do the right thing.
*
* If it's on_rq, then the dequeue_entity(.flags=0) will already
* have normalized the vruntime, if it's !on_rq, then only when
* If it's queued, then the dequeue_entity(.flags=0) will already
* have normalized the vruntime, if it's !queued, then only when
* the task is sleeping will it still have non-normalized vruntime.
*/
if (!p->on_rq && p->state != TASK_RUNNING) {
if (!task_on_rq_queued(p) && p->state != TASK_RUNNING) {
/*
* Fix up our vruntime so that the current sleep doesn't
* cause 'unlimited' sleep bonus.
@@ -7521,15 +7624,15 @@ static void switched_from_fair(struct rq *rq, struct task_struct *p)
*/
static void switched_to_fair(struct rq *rq, struct task_struct *p)
{
struct sched_entity *se = &p->se;
#ifdef CONFIG_FAIR_GROUP_SCHED
struct sched_entity *se = &p->se;
/*
* Since the real-depth could have been changed (only FAIR
* class maintain depth value), reset depth properly.
*/
se->depth = se->parent ? se->parent->depth + 1 : 0;
#endif
if (!se->on_rq)
if (!task_on_rq_queued(p))
return;
/*
@@ -7575,7 +7678,7 @@ void init_cfs_rq(struct cfs_rq *cfs_rq)
}
#ifdef CONFIG_FAIR_GROUP_SCHED
static void task_move_group_fair(struct task_struct *p, int on_rq)
static void task_move_group_fair(struct task_struct *p, int queued)
{
struct sched_entity *se = &p->se;
struct cfs_rq *cfs_rq;
@@ -7594,7 +7697,7 @@ static void task_move_group_fair(struct task_struct *p, int on_rq)
* fair sleeper stuff for the first placement, but who cares.
*/
/*
* When !on_rq, vruntime of the task has usually NOT been normalized.
* When !queued, vruntime of the task has usually NOT been normalized.
* But there are some cases where it has already been normalized:
*
* - Moving a forked child which is waiting for being woken up by
@@ -7605,14 +7708,14 @@ static void task_move_group_fair(struct task_struct *p, int on_rq)
* To prevent boost or penalty in the new cfs_rq caused by delta
* min_vruntime between the two cfs_rqs, we skip vruntime adjustment.
*/
if (!on_rq && (!se->sum_exec_runtime || p->state == TASK_WAKING))
on_rq = 1;
if (!queued && (!se->sum_exec_runtime || p->state == TASK_WAKING))
queued = 1;
if (!on_rq)
if (!queued)
se->vruntime -= cfs_rq_of(se)->min_vruntime;
set_task_rq(p, task_cpu(p));
se->depth = se->parent ? se->parent->depth + 1 : 0;
if (!on_rq) {
if (!queued) {
cfs_rq = cfs_rq_of(se);
se->vruntime += cfs_rq->min_vruntime;
#ifdef CONFIG_SMP

6
kernel/sched/idle.c
View File

@@ -147,6 +147,9 @@ use_default:
clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER, &dev->cpu))
goto use_default;
/* Take note of the planned idle state. */
idle_set_state(this_rq(), &drv->states[next_state]);
/*
* Enter the idle state previously returned by the governor decision.
* This function will block until an interrupt occurs and will take
@@ -154,6 +157,9 @@ use_default:
*/
entered_state = cpuidle_enter(drv, dev, next_state);
/* The cpu is no longer idle or about to enter idle. */
idle_set_state(this_rq(), NULL);
if (broadcast)
clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT, &dev->cpu);

21
kernel/sched/rt.c
View File

@@ -1448,7 +1448,7 @@ pick_next_task_rt(struct rq *rq, struct task_struct *prev)
* means a dl or stop task can slip in, in which case we need
* to re-start task selection.
*/
if (unlikely((rq->stop && rq->stop->on_rq) ||
if (unlikely((rq->stop && task_on_rq_queued(rq->stop)) ||
rq->dl.dl_nr_running))
return RETRY_TASK;
}
@@ -1468,8 +1468,7 @@ pick_next_task_rt(struct rq *rq, struct task_struct *prev)
p = _pick_next_task_rt(rq);
/* The running task is never eligible for pushing */
if (p)
dequeue_pushable_task(rq, p);
dequeue_pushable_task(rq, p);
set_post_schedule(rq);
@@ -1624,7 +1623,7 @@ static struct rq *find_lock_lowest_rq(struct task_struct *task, struct rq *rq)
!cpumask_test_cpu(lowest_rq->cpu,
tsk_cpus_allowed(task)) ||
task_running(rq, task) ||
!task->on_rq)) {
!task_on_rq_queued(task))) {
double_unlock_balance(rq, lowest_rq);
lowest_rq = NULL;
@@ -1658,7 +1657,7 @@ static struct task_struct *pick_next_pushable_task(struct rq *rq)
BUG_ON(task_current(rq, p));
BUG_ON(p->nr_cpus_allowed <= 1);
BUG_ON(!p->on_rq);
BUG_ON(!task_on_rq_queued(p));
BUG_ON(!rt_task(p));
return p;
@@ -1809,7 +1808,7 @@ static int pull_rt_task(struct rq *this_rq)
*/
if (p && (p->prio < this_rq->rt.highest_prio.curr)) {
WARN_ON(p == src_rq->curr);
WARN_ON(!p->on_rq);
WARN_ON(!task_on_rq_queued(p));
/*
* There's a chance that p is higher in priority
@@ -1870,7 +1869,7 @@ static void set_cpus_allowed_rt(struct task_struct *p,
BUG_ON(!rt_task(p));
if (!p->on_rq)
if (!task_on_rq_queued(p))
return;
weight = cpumask_weight(new_mask);
@@ -1936,7 +1935,7 @@ static void switched_from_rt(struct rq *rq, struct task_struct *p)
* we may need to handle the pulling of RT tasks
* now.
*/
if (!p->on_rq || rq->rt.rt_nr_running)
if (!task_on_rq_queued(p) || rq->rt.rt_nr_running)
return;
if (pull_rt_task(rq))
@@ -1970,7 +1969,7 @@ static void switched_to_rt(struct rq *rq, struct task_struct *p)
* If that current running task is also an RT task
* then see if we can move to another run queue.
*/
if (p->on_rq && rq->curr != p) {
if (task_on_rq_queued(p) && rq->curr != p) {
#ifdef CONFIG_SMP
if (p->nr_cpus_allowed > 1 && rq->rt.overloaded &&
/* Don't resched if we changed runqueues */
@@ -1989,7 +1988,7 @@ static void switched_to_rt(struct rq *rq, struct task_struct *p)
static void
prio_changed_rt(struct rq *rq, struct task_struct *p, int oldprio)
{
if (!p->on_rq)
if (!task_on_rq_queued(p))
return;
if (rq->curr == p) {
@@ -2073,7 +2072,7 @@ static void task_tick_rt(struct rq *rq, struct task_struct *p, int queued)
for_each_sched_rt_entity(rt_se) {
if (rt_se->run_list.prev != rt_se->run_list.next) {
requeue_task_rt(rq, p, 0);
set_tsk_need_resched(p);
resched_curr(rq);
return;
}
}

80
kernel/sched/sched.h
View File

@@ -14,6 +14,11 @@
#include "cpuacct.h"
struct rq;
struct cpuidle_state;
/* task_struct::on_rq states: */
#define TASK_ON_RQ_QUEUED 1
#define TASK_ON_RQ_MIGRATING 2
extern __read_mostly int scheduler_running;
@@ -126,6 +131,9 @@ struct rt_bandwidth {
u64 rt_runtime;
struct hrtimer rt_period_timer;
};
void __dl_clear_params(struct task_struct *p);
/*
* To keep the bandwidth of -deadline tasks and groups under control
* we need some place where:
@@ -184,7 +192,7 @@ struct cfs_bandwidth {
raw_spinlock_t lock;
ktime_t period;
u64 quota, runtime;
s64 hierarchal_quota;
s64 hierarchical_quota;
u64 runtime_expires;
int idle, timer_active;
@@ -636,6 +644,11 @@ struct rq {
#ifdef CONFIG_SMP
struct llist_head wake_list;
#endif
#ifdef CONFIG_CPU_IDLE
/* Must be inspected within a rcu lock section */
struct cpuidle_state *idle_state;
#endif
};
static inline int cpu_of(struct rq *rq)
@@ -647,7 +660,7 @@ static inline int cpu_of(struct rq *rq)
#endif
}
DECLARE_PER_CPU(struct rq, runqueues);
DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
#define cpu_rq(cpu) (&per_cpu(runqueues, (cpu)))
#define this_rq() (&__get_cpu_var(runqueues))
@@ -942,6 +955,15 @@ static inline int task_running(struct rq *rq, struct task_struct *p)
#endif
}
static inline int task_on_rq_queued(struct task_struct *p)
{
return p->on_rq == TASK_ON_RQ_QUEUED;
}
static inline int task_on_rq_migrating(struct task_struct *p)
{
return p->on_rq == TASK_ON_RQ_MIGRATING;
}
#ifndef prepare_arch_switch
# define prepare_arch_switch(next) do { } while (0)
@@ -953,7 +975,6 @@ static inline int task_running(struct rq *rq, struct task_struct *p)
# define finish_arch_post_lock_switch() do { } while (0)
#endif
#ifndef __ARCH_WANT_UNLOCKED_CTXSW
static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next)
{
#ifdef CONFIG_SMP
@@ -991,35 +1012,6 @@ static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev)
raw_spin_unlock_irq(&rq->lock);
}
#else /* __ARCH_WANT_UNLOCKED_CTXSW */
static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next)
{
#ifdef CONFIG_SMP
/*
* We can optimise this out completely for !SMP, because the
* SMP rebalancing from interrupt is the only thing that cares
* here.
*/
next->on_cpu = 1;
#endif
raw_spin_unlock(&rq->lock);
}
static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev)
{
#ifdef CONFIG_SMP
/*
* After ->on_cpu is cleared, the task can be moved to a different CPU.
* We must ensure this doesn't happen until the switch is completely
* finished.
*/
smp_wmb();
prev->on_cpu = 0;
#endif
local_irq_enable();
}
#endif /* __ARCH_WANT_UNLOCKED_CTXSW */
/*
* wake flags
*/
@@ -1180,6 +1172,30 @@ static inline void idle_exit_fair(struct rq *rq) { }
#endif
#ifdef CONFIG_CPU_IDLE
static inline void idle_set_state(struct rq *rq,
struct cpuidle_state *idle_state)
{
rq->idle_state = idle_state;
}
static inline struct cpuidle_state *idle_get_state(struct rq *rq)
{
WARN_ON(!rcu_read_lock_held());
return rq->idle_state;
}
#else
static inline void idle_set_state(struct rq *rq,
struct cpuidle_state *idle_state)
{
}
static inline struct cpuidle_state *idle_get_state(struct rq *rq)
{
return NULL;
}
#endif
extern void sysrq_sched_debug_show(void);
extern void sched_init_granularity(void);
extern void update_max_interval(void);

2
kernel/sched/stop_task.c
View File

@@ -28,7 +28,7 @@ pick_next_task_stop(struct rq *rq, struct task_struct *prev)
{
struct task_struct *stop = rq->stop;
if (!stop || !stop->on_rq)
if (!stop || !task_on_rq_queued(stop))
return NULL;
put_prev_task(rq, prev);

22
kernel/smp.c
View File

@@ -13,6 +13,7 @@
#include <linux/gfp.h>
#include <linux/smp.h>
#include <linux/cpu.h>
#include <linux/sched.h>
#include "smpboot.h"
@@ -699,3 +700,24 @@ void kick_all_cpus_sync(void)
smp_call_function(do_nothing, NULL, 1);
}
EXPORT_SYMBOL_GPL(kick_all_cpus_sync);
/**
* wake_up_all_idle_cpus - break all cpus out of idle
* wake_up_all_idle_cpus try to break all cpus which is in idle state even
* including idle polling cpus, for non-idle cpus, we will do nothing
* for them.
*/
void wake_up_all_idle_cpus(void)
{
int cpu;
preempt_disable();
for_each_online_cpu(cpu) {
if (cpu == smp_processor_id())
continue;
wake_up_if_idle(cpu);
}
preempt_enable();
}
EXPORT_SYMBOL_GPL(wake_up_all_idle_cpus);

2
kernel/sys.c
View File

@@ -869,11 +869,9 @@ void do_sys_times(struct tms *tms)
{
cputime_t tgutime, tgstime, cutime, cstime;
spin_lock_irq(&current->sighand->siglock);
thread_group_cputime_adjusted(current, &tgutime, &tgstime);
cutime = current->signal->cutime;
cstime = current->signal->cstime;
spin_unlock_irq(&current->sighand->siglock);
tms->tms_utime = cputime_to_clock_t(tgutime);
tms->tms_stime = cputime_to_clock_t(tgstime);
tms->tms_cutime = cputime_to_clock_t(cutime);

1
kernel/time/hrtimer.c
View File

@@ -1776,7 +1776,6 @@ schedule_hrtimeout_range_clock(ktime_t *expires, unsigned long delta,
*/
if (!expires) {
schedule();
__set_current_state(TASK_RUNNING);
return -EINTR;
}

14
kernel/time/posix-cpu-timers.c
View File

@@ -272,22 +272,8 @@ static int posix_cpu_clock_get_task(struct task_struct *tsk,
if (same_thread_group(tsk, current))
err = cpu_clock_sample(which_clock, tsk, &rtn);
} else {
unsigned long flags;
struct sighand_struct *sighand;
/*
* while_each_thread() is not yet entirely RCU safe,
* keep locking the group while sampling process
* clock for now.
*/
sighand = lock_task_sighand(tsk, &flags);
if (!sighand)
return err;
if (tsk == current || thread_group_leader(tsk))
err = cpu_clock_sample_group(which_clock, tsk, &rtn);
unlock_task_sighand(tsk, &flags);
}
if (!err)

3
kernel/trace/ring_buffer_benchmark.c
View File

@@ -205,7 +205,6 @@ static void ring_buffer_consumer(void)
break;
schedule();
__set_current_state(TASK_RUNNING);
}
reader_finish = 0;
complete(&read_done);
@@ -379,7 +378,6 @@ static int ring_buffer_consumer_thread(void *arg)
break;
schedule();
__set_current_state(TASK_RUNNING);
}
__set_current_state(TASK_RUNNING);
@@ -407,7 +405,6 @@ static int ring_buffer_producer_thread(void *arg)
trace_printk("Sleeping for 10 secs\n");
set_current_state(TASK_INTERRUPTIBLE);
schedule_timeout(HZ * SLEEP_TIME);
__set_current_state(TASK_RUNNING);
}
if (kill_test)

4
kernel/trace/trace_stack.c
View File

@@ -13,7 +13,6 @@
#include <linux/sysctl.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/magic.h>
#include <asm/setup.h>
@@ -171,8 +170,7 @@ check_stack(unsigned long ip, unsigned long *stack)
i++;
}
if ((current != &init_task &&
*(end_of_stack(current)) != STACK_END_MAGIC)) {
if (task_stack_end_corrupted(current)) {
print_max_stack();
BUG();
}