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Diffstat (limited to 'kernel/sched/core.c')
-rw-r--r--kernel/sched/core.c83
1 files changed, 55 insertions, 28 deletions
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index e1ae6ac15eac..3b31fc05a0f1 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -6,10 +6,15 @@
* Copyright (C) 1991-2002 Linus Torvalds
*/
#include <linux/sched.h>
+#include <linux/sched/clock.h>
+#include <uapi/linux/sched/types.h>
+#include <linux/sched/loadavg.h>
+#include <linux/sched/hotplug.h>
#include <linux/cpuset.h>
#include <linux/delayacct.h>
#include <linux/init_task.h>
#include <linux/context_tracking.h>
+#include <linux/rcupdate_wait.h>
#include <linux/blkdev.h>
#include <linux/kprobes.h>
@@ -981,7 +986,7 @@ static struct rq *__migrate_task(struct rq *rq, struct task_struct *p, int dest_
return rq;
/* Affinity changed (again). */
- if (!cpumask_test_cpu(dest_cpu, tsk_cpus_allowed(p)))
+ if (!cpumask_test_cpu(dest_cpu, &p->cpus_allowed))
return rq;
rq = move_queued_task(rq, p, dest_cpu);
@@ -1090,6 +1095,7 @@ static int __set_cpus_allowed_ptr(struct task_struct *p,
int ret = 0;
rq = task_rq_lock(p, &rf);
+ update_rq_clock(rq);
if (p->flags & PF_KTHREAD) {
/*
@@ -1258,10 +1264,10 @@ static int migrate_swap_stop(void *data)
if (task_cpu(arg->src_task) != arg->src_cpu)
goto unlock;
- if (!cpumask_test_cpu(arg->dst_cpu, tsk_cpus_allowed(arg->src_task)))
+ if (!cpumask_test_cpu(arg->dst_cpu, &arg->src_task->cpus_allowed))
goto unlock;
- if (!cpumask_test_cpu(arg->src_cpu, tsk_cpus_allowed(arg->dst_task)))
+ if (!cpumask_test_cpu(arg->src_cpu, &arg->dst_task->cpus_allowed))
goto unlock;
__migrate_swap_task(arg->src_task, arg->dst_cpu);
@@ -1302,10 +1308,10 @@ int migrate_swap(struct task_struct *cur, struct task_struct *p)
if (!cpu_active(arg.src_cpu) || !cpu_active(arg.dst_cpu))
goto out;
- if (!cpumask_test_cpu(arg.dst_cpu, tsk_cpus_allowed(arg.src_task)))
+ if (!cpumask_test_cpu(arg.dst_cpu, &arg.src_task->cpus_allowed))
goto out;
- if (!cpumask_test_cpu(arg.src_cpu, tsk_cpus_allowed(arg.dst_task)))
+ if (!cpumask_test_cpu(arg.src_cpu, &arg.dst_task->cpus_allowed))
goto out;
trace_sched_swap_numa(cur, arg.src_cpu, p, arg.dst_cpu);
@@ -1489,14 +1495,14 @@ static int select_fallback_rq(int cpu, struct task_struct *p)
for_each_cpu(dest_cpu, nodemask) {
if (!cpu_active(dest_cpu))
continue;
- if (cpumask_test_cpu(dest_cpu, tsk_cpus_allowed(p)))
+ if (cpumask_test_cpu(dest_cpu, &p->cpus_allowed))
return dest_cpu;
}
}
for (;;) {
/* Any allowed, online CPU? */
- for_each_cpu(dest_cpu, tsk_cpus_allowed(p)) {
+ for_each_cpu(dest_cpu, &p->cpus_allowed) {
if (!(p->flags & PF_KTHREAD) && !cpu_active(dest_cpu))
continue;
if (!cpu_online(dest_cpu))
@@ -1548,10 +1554,10 @@ int select_task_rq(struct task_struct *p, int cpu, int sd_flags, int wake_flags)
{
lockdep_assert_held(&p->pi_lock);
- if (tsk_nr_cpus_allowed(p) > 1)
+ if (p->nr_cpus_allowed > 1)
cpu = p->sched_class->select_task_rq(p, cpu, sd_flags, wake_flags);
else
- cpu = cpumask_any(tsk_cpus_allowed(p));
+ cpu = cpumask_any(&p->cpus_allowed);
/*
* In order not to call set_task_cpu() on a blocking task we need
@@ -1563,7 +1569,7 @@ int select_task_rq(struct task_struct *p, int cpu, 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, tsk_cpus_allowed(p)) ||
+ if (unlikely(!cpumask_test_cpu(cpu, &p->cpus_allowed) ||
!cpu_online(cpu)))
cpu = select_fallback_rq(task_cpu(p), p);
@@ -2847,7 +2853,7 @@ context_switch(struct rq *rq, struct task_struct *prev,
if (!mm) {
next->active_mm = oldmm;
- atomic_inc(&oldmm->mm_count);
+ mmgrab(oldmm);
enter_lazy_tlb(oldmm, next);
} else
switch_mm_irqs_off(oldmm, mm, next);
@@ -3210,6 +3216,15 @@ static inline void preempt_latency_start(int val) { }
static inline void preempt_latency_stop(int val) { }
#endif
+static inline unsigned long get_preempt_disable_ip(struct task_struct *p)
+{
+#ifdef CONFIG_DEBUG_PREEMPT
+ return p->preempt_disable_ip;
+#else
+ return 0;
+#endif
+}
+
/*
* Print scheduling while atomic bug:
*/
@@ -3272,10 +3287,15 @@ pick_next_task(struct rq *rq, struct task_struct *prev, struct rq_flags *rf)
struct task_struct *p;
/*
- * Optimization: we know that if all tasks are in
- * the fair class we can call that function directly:
+ * Optimization: we know that if all tasks are in the fair class we can
+ * call that function directly, but only if the @prev task wasn't of a
+ * higher scheduling class, because otherwise those loose the
+ * opportunity to pull in more work from other CPUs.
*/
- if (likely(rq->nr_running == rq->cfs.h_nr_running)) {
+ if (likely((prev->sched_class == &idle_sched_class ||
+ prev->sched_class == &fair_sched_class) &&
+ rq->nr_running == rq->cfs.h_nr_running)) {
+
p = fair_sched_class.pick_next_task(rq, prev, rf);
if (unlikely(p == RETRY_TASK))
goto again;
@@ -5232,6 +5252,9 @@ void sched_show_task(struct task_struct *p)
int ppid;
unsigned long state = p->state;
+ /* Make sure the string lines up properly with the number of task states: */
+ BUILD_BUG_ON(sizeof(TASK_STATE_TO_CHAR_STR)-1 != ilog2(TASK_STATE_MAX)+1);
+
if (!try_get_task_stack(p))
return;
if (state)
@@ -5460,7 +5483,7 @@ int migrate_task_to(struct task_struct *p, int target_cpu)
if (curr_cpu == target_cpu)
return 0;
- if (!cpumask_test_cpu(target_cpu, tsk_cpus_allowed(p)))
+ if (!cpumask_test_cpu(target_cpu, &p->cpus_allowed))
return -EINVAL;
/* TODO: This is not properly updating schedstats */
@@ -5560,7 +5583,7 @@ static void migrate_tasks(struct rq *dead_rq)
{
struct rq *rq = dead_rq;
struct task_struct *next, *stop = rq->stop;
- struct rq_flags rf, old_rf;
+ struct rq_flags rf;
int dest_cpu;
/*
@@ -5579,7 +5602,9 @@ static void migrate_tasks(struct rq *dead_rq)
* class method both need to have an up-to-date
* value of rq->clock[_task]
*/
+ rq_pin_lock(rq, &rf);
update_rq_clock(rq);
+ rq_unpin_lock(rq, &rf);
for (;;) {
/*
@@ -5592,7 +5617,7 @@ static void migrate_tasks(struct rq *dead_rq)
/*
* pick_next_task() assumes pinned rq->lock:
*/
- rq_pin_lock(rq, &rf);
+ rq_repin_lock(rq, &rf);
next = pick_next_task(rq, &fake_task, &rf);
BUG_ON(!next);
next->sched_class->put_prev_task(rq, next);
@@ -5621,13 +5646,6 @@ static void migrate_tasks(struct rq *dead_rq)
continue;
}
- /*
- * __migrate_task() may return with a different
- * rq->lock held and a new cookie in 'rf', but we need
- * to preserve rf::clock_update_flags for 'dead_rq'.
- */
- old_rf = rf;
-
/* Find suitable destination for @next, with force if needed. */
dest_cpu = select_fallback_rq(dead_rq->cpu, next);
@@ -5636,7 +5654,6 @@ static void migrate_tasks(struct rq *dead_rq)
raw_spin_unlock(&rq->lock);
rq = dead_rq;
raw_spin_lock(&rq->lock);
- rf = old_rf;
}
raw_spin_unlock(&next->pi_lock);
}
@@ -6098,7 +6115,7 @@ void __init sched_init(void)
/*
* The boot idle thread does lazy MMU switching as well:
*/
- atomic_inc(&init_mm.mm_count);
+ mmgrab(&init_mm);
enter_lazy_tlb(&init_mm, current);
/*
@@ -6819,11 +6836,20 @@ cpu_cgroup_css_alloc(struct cgroup_subsys_state *parent_css)
if (IS_ERR(tg))
return ERR_PTR(-ENOMEM);
- sched_online_group(tg, parent);
-
return &tg->css;
}
+/* Expose task group only after completing cgroup initialization */
+static int cpu_cgroup_css_online(struct cgroup_subsys_state *css)
+{
+ struct task_group *tg = css_tg(css);
+ struct task_group *parent = css_tg(css->parent);
+
+ if (parent)
+ sched_online_group(tg, parent);
+ return 0;
+}
+
static void cpu_cgroup_css_released(struct cgroup_subsys_state *css)
{
struct task_group *tg = css_tg(css);
@@ -7229,6 +7255,7 @@ static struct cftype cpu_files[] = {
struct cgroup_subsys cpu_cgrp_subsys = {
.css_alloc = cpu_cgroup_css_alloc,
+ .css_online = cpu_cgroup_css_online,
.css_released = cpu_cgroup_css_released,
.css_free = cpu_cgroup_css_free,
.fork = cpu_cgroup_fork,