diff options
Diffstat (limited to 'kernel/sched/core.c')
-rw-r--r-- | kernel/sched/core.c | 83 |
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, |