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authorThomas Gleixner <tglx@linutronix.de>2018-08-05 16:39:29 +0200
committerThomas Gleixner <tglx@linutronix.de>2018-08-05 16:39:29 +0200
commitf2701b77bbd992f3df4631de8493f21db0830452 (patch)
treeb05b2bf8b47002ae81c79aaa9de2a311b8ee075e /kernel/sched
parent18b57ce2eb8c8b9a24174a89250cf5f57c76ecdc (diff)
parentacb1872577b346bd15ab3a3f8dff780d6cca4b70 (diff)
Merge 4.18-rc7 into master to pick up the KVM dependcy
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'kernel/sched')
-rw-r--r--kernel/sched/core.c67
-rw-r--r--kernel/sched/cpufreq_schedutil.c2
-rw-r--r--kernel/sched/deadline.c11
-rw-r--r--kernel/sched/fair.c45
-rw-r--r--kernel/sched/rt.c16
-rw-r--r--kernel/sched/sched.h11
6 files changed, 84 insertions, 68 deletions
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 0f79bb5ffb5a..5ba96d9ddbde 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -7,7 +7,6 @@
*/
#include "sched.h"
-#include <linux/kthread.h>
#include <linux/nospec.h>
#include <linux/kcov.h>
@@ -2724,28 +2723,20 @@ static struct rq *finish_task_switch(struct task_struct *prev)
membarrier_mm_sync_core_before_usermode(mm);
mmdrop(mm);
}
- if (unlikely(prev_state & (TASK_DEAD|TASK_PARKED))) {
- switch (prev_state) {
- case TASK_DEAD:
- if (prev->sched_class->task_dead)
- prev->sched_class->task_dead(prev);
+ if (unlikely(prev_state == TASK_DEAD)) {
+ if (prev->sched_class->task_dead)
+ prev->sched_class->task_dead(prev);
- /*
- * Remove function-return probe instances associated with this
- * task and put them back on the free list.
- */
- kprobe_flush_task(prev);
-
- /* Task is done with its stack. */
- put_task_stack(prev);
+ /*
+ * Remove function-return probe instances associated with this
+ * task and put them back on the free list.
+ */
+ kprobe_flush_task(prev);
- put_task_struct(prev);
- break;
+ /* Task is done with its stack. */
+ put_task_stack(prev);
- case TASK_PARKED:
- kthread_park_complete(prev);
- break;
- }
+ put_task_struct(prev);
}
tick_nohz_task_switch();
@@ -3113,7 +3104,9 @@ static void sched_tick_remote(struct work_struct *work)
struct tick_work *twork = container_of(dwork, struct tick_work, work);
int cpu = twork->cpu;
struct rq *rq = cpu_rq(cpu);
+ struct task_struct *curr;
struct rq_flags rf;
+ u64 delta;
/*
* Handle the tick only if it appears the remote CPU is running in full
@@ -3122,24 +3115,28 @@ static void sched_tick_remote(struct work_struct *work)
* statistics and checks timeslices in a time-independent way, regardless
* of when exactly it is running.
*/
- if (!idle_cpu(cpu) && tick_nohz_tick_stopped_cpu(cpu)) {
- struct task_struct *curr;
- u64 delta;
+ if (idle_cpu(cpu) || !tick_nohz_tick_stopped_cpu(cpu))
+ goto out_requeue;
- rq_lock_irq(rq, &rf);
- update_rq_clock(rq);
- curr = rq->curr;
- delta = rq_clock_task(rq) - curr->se.exec_start;
+ rq_lock_irq(rq, &rf);
+ curr = rq->curr;
+ if (is_idle_task(curr))
+ goto out_unlock;
- /*
- * Make sure the next tick runs within a reasonable
- * amount of time.
- */
- WARN_ON_ONCE(delta > (u64)NSEC_PER_SEC * 3);
- curr->sched_class->task_tick(rq, curr, 0);
- rq_unlock_irq(rq, &rf);
- }
+ update_rq_clock(rq);
+ delta = rq_clock_task(rq) - curr->se.exec_start;
+
+ /*
+ * Make sure the next tick runs within a reasonable
+ * amount of time.
+ */
+ WARN_ON_ONCE(delta > (u64)NSEC_PER_SEC * 3);
+ curr->sched_class->task_tick(rq, curr, 0);
+
+out_unlock:
+ rq_unlock_irq(rq, &rf);
+out_requeue:
/*
* Run the remote tick once per second (1Hz). This arbitrary
* frequency is large enough to avoid overload but short enough
diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c
index 3cde46483f0a..c907fde01eaa 100644
--- a/kernel/sched/cpufreq_schedutil.c
+++ b/kernel/sched/cpufreq_schedutil.c
@@ -192,7 +192,7 @@ static unsigned long sugov_aggregate_util(struct sugov_cpu *sg_cpu)
{
struct rq *rq = cpu_rq(sg_cpu->cpu);
- if (rq->rt.rt_nr_running)
+ if (rt_rq_is_runnable(&rq->rt))
return sg_cpu->max;
/*
diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index fbfc3f1d368a..10c7b51c0d1f 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -2290,8 +2290,17 @@ static void switched_from_dl(struct rq *rq, struct task_struct *p)
if (task_on_rq_queued(p) && p->dl.dl_runtime)
task_non_contending(p);
- if (!task_on_rq_queued(p))
+ if (!task_on_rq_queued(p)) {
+ /*
+ * Inactive timer is armed. However, p is leaving DEADLINE and
+ * might migrate away from this rq while continuing to run on
+ * some other class. We need to remove its contribution from
+ * this rq running_bw now, or sub_rq_bw (below) will complain.
+ */
+ if (p->dl.dl_non_contending)
+ sub_running_bw(&p->dl, &rq->dl);
sub_rq_bw(&p->dl, &rq->dl);
+ }
/*
* We cannot use inactive_task_timer() to invoke sub_running_bw()
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index cacdbef99b95..9c219f7b0970 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -3982,18 +3982,10 @@ util_est_dequeue(struct cfs_rq *cfs_rq, struct task_struct *p, bool task_sleep)
if (!sched_feat(UTIL_EST))
return;
- /*
- * Update root cfs_rq's estimated utilization
- *
- * If *p is the last task then the root cfs_rq's estimated utilization
- * of a CPU is 0 by definition.
- */
- ue.enqueued = 0;
- if (cfs_rq->nr_running) {
- ue.enqueued = cfs_rq->avg.util_est.enqueued;
- ue.enqueued -= min_t(unsigned int, ue.enqueued,
- (_task_util_est(p) | UTIL_AVG_UNCHANGED));
- }
+ /* Update root cfs_rq's estimated utilization */
+ ue.enqueued = cfs_rq->avg.util_est.enqueued;
+ ue.enqueued -= min_t(unsigned int, ue.enqueued,
+ (_task_util_est(p) | UTIL_AVG_UNCHANGED));
WRITE_ONCE(cfs_rq->avg.util_est.enqueued, ue.enqueued);
/*
@@ -4590,6 +4582,7 @@ void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b)
now = sched_clock_cpu(smp_processor_id());
cfs_b->runtime = cfs_b->quota;
cfs_b->runtime_expires = now + ktime_to_ns(cfs_b->period);
+ cfs_b->expires_seq++;
}
static inline struct cfs_bandwidth *tg_cfs_bandwidth(struct task_group *tg)
@@ -4612,6 +4605,7 @@ static int assign_cfs_rq_runtime(struct cfs_rq *cfs_rq)
struct task_group *tg = cfs_rq->tg;
struct cfs_bandwidth *cfs_b = tg_cfs_bandwidth(tg);
u64 amount = 0, min_amount, expires;
+ int expires_seq;
/* note: this is a positive sum as runtime_remaining <= 0 */
min_amount = sched_cfs_bandwidth_slice() - cfs_rq->runtime_remaining;
@@ -4628,6 +4622,7 @@ static int assign_cfs_rq_runtime(struct cfs_rq *cfs_rq)
cfs_b->idle = 0;
}
}
+ expires_seq = cfs_b->expires_seq;
expires = cfs_b->runtime_expires;
raw_spin_unlock(&cfs_b->lock);
@@ -4637,8 +4632,10 @@ static int assign_cfs_rq_runtime(struct cfs_rq *cfs_rq)
* spread between our sched_clock and the one on which runtime was
* issued.
*/
- if ((s64)(expires - cfs_rq->runtime_expires) > 0)
+ if (cfs_rq->expires_seq != expires_seq) {
+ cfs_rq->expires_seq = expires_seq;
cfs_rq->runtime_expires = expires;
+ }
return cfs_rq->runtime_remaining > 0;
}
@@ -4664,12 +4661,9 @@ static void expire_cfs_rq_runtime(struct cfs_rq *cfs_rq)
* has not truly expired.
*
* Fortunately we can check determine whether this the case by checking
- * whether the global deadline has advanced. It is valid to compare
- * cfs_b->runtime_expires without any locks since we only care about
- * exact equality, so a partial write will still work.
+ * whether the global deadline(cfs_b->expires_seq) has advanced.
*/
-
- if (cfs_rq->runtime_expires != cfs_b->runtime_expires) {
+ if (cfs_rq->expires_seq == cfs_b->expires_seq) {
/* extend local deadline, drift is bounded above by 2 ticks */
cfs_rq->runtime_expires += TICK_NSEC;
} else {
@@ -5202,13 +5196,18 @@ static void init_cfs_rq_runtime(struct cfs_rq *cfs_rq)
void start_cfs_bandwidth(struct cfs_bandwidth *cfs_b)
{
+ u64 overrun;
+
lockdep_assert_held(&cfs_b->lock);
- if (!cfs_b->period_active) {
- cfs_b->period_active = 1;
- hrtimer_forward_now(&cfs_b->period_timer, cfs_b->period);
- hrtimer_start_expires(&cfs_b->period_timer, HRTIMER_MODE_ABS_PINNED);
- }
+ if (cfs_b->period_active)
+ return;
+
+ cfs_b->period_active = 1;
+ overrun = hrtimer_forward_now(&cfs_b->period_timer, cfs_b->period);
+ cfs_b->runtime_expires += (overrun + 1) * ktime_to_ns(cfs_b->period);
+ cfs_b->expires_seq++;
+ hrtimer_start_expires(&cfs_b->period_timer, HRTIMER_MODE_ABS_PINNED);
}
static void destroy_cfs_bandwidth(struct cfs_bandwidth *cfs_b)
diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c
index 47556b0c9a95..572567078b60 100644
--- a/kernel/sched/rt.c
+++ b/kernel/sched/rt.c
@@ -508,8 +508,11 @@ static void sched_rt_rq_dequeue(struct rt_rq *rt_rq)
rt_se = rt_rq->tg->rt_se[cpu];
- if (!rt_se)
+ if (!rt_se) {
dequeue_top_rt_rq(rt_rq);
+ /* Kick cpufreq (see the comment in kernel/sched/sched.h). */
+ cpufreq_update_util(rq_of_rt_rq(rt_rq), 0);
+ }
else if (on_rt_rq(rt_se))
dequeue_rt_entity(rt_se, 0);
}
@@ -1001,8 +1004,6 @@ dequeue_top_rt_rq(struct rt_rq *rt_rq)
sub_nr_running(rq, rt_rq->rt_nr_running);
rt_rq->rt_queued = 0;
- /* Kick cpufreq (see the comment in kernel/sched/sched.h). */
- cpufreq_update_util(rq, 0);
}
static void
@@ -1014,11 +1015,14 @@ enqueue_top_rt_rq(struct rt_rq *rt_rq)
if (rt_rq->rt_queued)
return;
- if (rt_rq_throttled(rt_rq) || !rt_rq->rt_nr_running)
+
+ if (rt_rq_throttled(rt_rq))
return;
- add_nr_running(rq, rt_rq->rt_nr_running);
- rt_rq->rt_queued = 1;
+ if (rt_rq->rt_nr_running) {
+ add_nr_running(rq, rt_rq->rt_nr_running);
+ rt_rq->rt_queued = 1;
+ }
/* Kick cpufreq (see the comment in kernel/sched/sched.h). */
cpufreq_update_util(rq, 0);
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index 6601baf2361c..c7742dcc136c 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -334,9 +334,10 @@ struct cfs_bandwidth {
u64 runtime;
s64 hierarchical_quota;
u64 runtime_expires;
+ int expires_seq;
- int idle;
- int period_active;
+ short idle;
+ short period_active;
struct hrtimer period_timer;
struct hrtimer slack_timer;
struct list_head throttled_cfs_rq;
@@ -551,6 +552,7 @@ struct cfs_rq {
#ifdef CONFIG_CFS_BANDWIDTH
int runtime_enabled;
+ int expires_seq;
u64 runtime_expires;
s64 runtime_remaining;
@@ -609,6 +611,11 @@ struct rt_rq {
#endif
};
+static inline bool rt_rq_is_runnable(struct rt_rq *rt_rq)
+{
+ return rt_rq->rt_queued && rt_rq->rt_nr_running;
+}
+
/* Deadline class' related fields in a runqueue */
struct dl_rq {
/* runqueue is an rbtree, ordered by deadline */