diff options
Diffstat (limited to 'kernel/sched/core.c')
| -rw-r--r-- | kernel/sched/core.c | 175 |
1 files changed, 106 insertions, 69 deletions
diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 5bd8d7e7347d..62b3416f5e43 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -66,6 +66,7 @@ #include <linux/vtime.h> #include <linux/wait_api.h> #include <linux/workqueue_api.h> +#include <linux/livepatch_sched.h> #ifdef CONFIG_PREEMPT_DYNAMIC # ifdef CONFIG_GENERIC_ENTRY @@ -488,6 +489,16 @@ sched_core_dequeue(struct rq *rq, struct task_struct *p, int flags) { } #endif /* CONFIG_SCHED_CORE */ +/* need a wrapper since we may need to trace from modules */ +EXPORT_TRACEPOINT_SYMBOL(sched_set_state_tp); + +/* Call via the helper macro trace_set_current_state. */ +void __trace_set_current_state(int state_value) +{ + trace_sched_set_state_tp(current, state_value); +} +EXPORT_SYMBOL(__trace_set_current_state); + /* * Serialization rules: * @@ -912,8 +923,7 @@ static void hrtick_rq_init(struct rq *rq) #ifdef CONFIG_SMP INIT_CSD(&rq->hrtick_csd, __hrtick_start, rq); #endif - hrtimer_init(&rq->hrtick_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_HARD); - rq->hrtick_timer.function = hrtick; + hrtimer_setup(&rq->hrtick_timer, hrtick, CLOCK_MONOTONIC, HRTIMER_MODE_REL_HARD); } #else /* CONFIG_SCHED_HRTICK */ static inline void hrtick_clear(struct rq *rq) @@ -1743,7 +1753,7 @@ static inline void uclamp_rq_dec_id(struct rq *rq, struct task_struct *p, } } -static inline void uclamp_rq_inc(struct rq *rq, struct task_struct *p) +static inline void uclamp_rq_inc(struct rq *rq, struct task_struct *p, int flags) { enum uclamp_id clamp_id; @@ -1759,7 +1769,8 @@ static inline void uclamp_rq_inc(struct rq *rq, struct task_struct *p) if (unlikely(!p->sched_class->uclamp_enabled)) return; - if (p->se.sched_delayed) + /* Only inc the delayed task which being woken up. */ + if (p->se.sched_delayed && !(flags & ENQUEUE_DELAYED)) return; for_each_clamp_id(clamp_id) @@ -2027,7 +2038,7 @@ static void __init init_uclamp(void) } #else /* !CONFIG_UCLAMP_TASK */ -static inline void uclamp_rq_inc(struct rq *rq, struct task_struct *p) { } +static inline void uclamp_rq_inc(struct rq *rq, struct task_struct *p, int flags) { } static inline void uclamp_rq_dec(struct rq *rq, struct task_struct *p) { } static inline void uclamp_fork(struct task_struct *p) { } static inline void uclamp_post_fork(struct task_struct *p) { } @@ -2063,12 +2074,14 @@ void enqueue_task(struct rq *rq, struct task_struct *p, int flags) if (!(flags & ENQUEUE_NOCLOCK)) update_rq_clock(rq); - p->sched_class->enqueue_task(rq, p, flags); /* - * Must be after ->enqueue_task() because ENQUEUE_DELAYED can clear - * ->sched_delayed. + * Can be before ->enqueue_task() because uclamp considers the + * ENQUEUE_DELAYED task before its ->sched_delayed gets cleared + * in ->enqueue_task(). */ - uclamp_rq_inc(rq, p); + uclamp_rq_inc(rq, p, flags); + + p->sched_class->enqueue_task(rq, p, flags); psi_enqueue(p, flags); @@ -2274,6 +2287,12 @@ unsigned long wait_task_inactive(struct task_struct *p, unsigned int match_state * just go back and repeat. */ rq = task_rq_lock(p, &rf); + /* + * If task is sched_delayed, force dequeue it, to avoid always + * hitting the tick timeout in the queued case + */ + if (p->se.sched_delayed) + dequeue_task(rq, p, DEQUEUE_SLEEP | DEQUEUE_DELAYED); trace_sched_wait_task(p); running = task_on_cpu(rq, p); queued = task_on_rq_queued(p); @@ -5296,6 +5315,12 @@ asmlinkage __visible void schedule_tail(struct task_struct *prev) */ finish_task_switch(prev); + /* + * This is a special case: the newly created task has just + * switched the context for the first time. It is returning from + * schedule for the first time in this path. + */ + trace_sched_exit_tp(true, CALLER_ADDR0); preempt_enable(); if (current->set_child_tid) @@ -6556,12 +6581,14 @@ pick_next_task(struct rq *rq, struct task_struct *prev, struct rq_flags *rf) * Otherwise marks the task's __state as RUNNING */ static bool try_to_block_task(struct rq *rq, struct task_struct *p, - unsigned long task_state) + unsigned long *task_state_p) { + unsigned long task_state = *task_state_p; int flags = DEQUEUE_NOCLOCK; if (signal_pending_state(task_state, p)) { WRITE_ONCE(p->__state, TASK_RUNNING); + *task_state_p = TASK_RUNNING; return false; } @@ -6635,12 +6662,15 @@ static void __sched notrace __schedule(int sched_mode) * as a preemption by schedule_debug() and RCU. */ bool preempt = sched_mode > SM_NONE; + bool is_switch = false; unsigned long *switch_count; unsigned long prev_state; struct rq_flags rf; struct rq *rq; int cpu; + trace_sched_entry_tp(preempt, CALLER_ADDR0); + cpu = smp_processor_id(); rq = cpu_rq(cpu); prev = rq->curr; @@ -6650,6 +6680,8 @@ static void __sched notrace __schedule(int sched_mode) if (sched_feat(HRTICK) || sched_feat(HRTICK_DL)) hrtick_clear(rq); + klp_sched_try_switch(prev); + local_irq_disable(); rcu_note_context_switch(preempt); @@ -6695,7 +6727,7 @@ static void __sched notrace __schedule(int sched_mode) goto picked; } } else if (!preempt && prev_state) { - try_to_block_task(rq, prev, prev_state); + try_to_block_task(rq, prev, &prev_state); switch_count = &prev->nvcsw; } @@ -6706,7 +6738,8 @@ picked: clear_preempt_need_resched(); rq->last_seen_need_resched_ns = 0; - if (likely(prev != next)) { + is_switch = prev != next; + if (likely(is_switch)) { rq->nr_switches++; /* * RCU users of rcu_dereference(rq->curr) may not see @@ -6751,6 +6784,7 @@ picked: __balance_callbacks(rq); raw_spin_rq_unlock_irq(rq); } + trace_sched_exit_tp(is_switch, CALLER_ADDR0); } void __noreturn do_task_dead(void) @@ -7308,7 +7342,6 @@ EXPORT_STATIC_CALL_TRAMP(might_resched); static DEFINE_STATIC_KEY_FALSE(sk_dynamic_cond_resched); int __sched dynamic_cond_resched(void) { - klp_sched_try_switch(); if (!static_branch_unlikely(&sk_dynamic_cond_resched)) return 0; return __cond_resched(); @@ -7480,7 +7513,6 @@ int sched_dynamic_mode(const char *str) #endif static DEFINE_MUTEX(sched_dynamic_mutex); -static bool klp_override; static void __sched_dynamic_update(int mode) { @@ -7488,8 +7520,7 @@ static void __sched_dynamic_update(int mode) * Avoid {NONE,VOLUNTARY} -> FULL transitions from ever ending up in * the ZERO state, which is invalid. */ - if (!klp_override) - preempt_dynamic_enable(cond_resched); + preempt_dynamic_enable(cond_resched); preempt_dynamic_enable(might_resched); preempt_dynamic_enable(preempt_schedule); preempt_dynamic_enable(preempt_schedule_notrace); @@ -7498,8 +7529,7 @@ static void __sched_dynamic_update(int mode) switch (mode) { case preempt_dynamic_none: - if (!klp_override) - preempt_dynamic_enable(cond_resched); + preempt_dynamic_enable(cond_resched); preempt_dynamic_disable(might_resched); preempt_dynamic_disable(preempt_schedule); preempt_dynamic_disable(preempt_schedule_notrace); @@ -7510,8 +7540,7 @@ static void __sched_dynamic_update(int mode) break; case preempt_dynamic_voluntary: - if (!klp_override) - preempt_dynamic_enable(cond_resched); + preempt_dynamic_enable(cond_resched); preempt_dynamic_enable(might_resched); preempt_dynamic_disable(preempt_schedule); preempt_dynamic_disable(preempt_schedule_notrace); @@ -7522,8 +7551,7 @@ static void __sched_dynamic_update(int mode) break; case preempt_dynamic_full: - if (!klp_override) - preempt_dynamic_disable(cond_resched); + preempt_dynamic_disable(cond_resched); preempt_dynamic_disable(might_resched); preempt_dynamic_enable(preempt_schedule); preempt_dynamic_enable(preempt_schedule_notrace); @@ -7534,8 +7562,7 @@ static void __sched_dynamic_update(int mode) break; case preempt_dynamic_lazy: - if (!klp_override) - preempt_dynamic_disable(cond_resched); + preempt_dynamic_disable(cond_resched); preempt_dynamic_disable(might_resched); preempt_dynamic_enable(preempt_schedule); preempt_dynamic_enable(preempt_schedule_notrace); @@ -7556,36 +7583,6 @@ void sched_dynamic_update(int mode) mutex_unlock(&sched_dynamic_mutex); } -#ifdef CONFIG_HAVE_PREEMPT_DYNAMIC_CALL - -static int klp_cond_resched(void) -{ - __klp_sched_try_switch(); - return __cond_resched(); -} - -void sched_dynamic_klp_enable(void) -{ - mutex_lock(&sched_dynamic_mutex); - - klp_override = true; - static_call_update(cond_resched, klp_cond_resched); - - mutex_unlock(&sched_dynamic_mutex); -} - -void sched_dynamic_klp_disable(void) -{ - mutex_lock(&sched_dynamic_mutex); - - klp_override = false; - __sched_dynamic_update(preempt_dynamic_mode); - - mutex_unlock(&sched_dynamic_mutex); -} - -#endif /* CONFIG_HAVE_PREEMPT_DYNAMIC_CALL */ - static int __init setup_preempt_mode(char *str) { int mode = sched_dynamic_mode(str); @@ -8998,7 +8995,7 @@ void sched_online_group(struct task_group *tg, struct task_group *parent) unsigned long flags; spin_lock_irqsave(&task_group_lock, flags); - list_add_rcu(&tg->list, &task_groups); + list_add_tail_rcu(&tg->list, &task_groups); /* Root should already exist: */ WARN_ON(!parent); @@ -9184,11 +9181,15 @@ static int cpu_cgroup_can_attach(struct cgroup_taskset *tset) struct task_struct *task; struct cgroup_subsys_state *css; + if (!rt_group_sched_enabled()) + goto scx_check; + cgroup_taskset_for_each(task, css, tset) { if (!sched_rt_can_attach(css_tg(css), task)) return -EINVAL; } -#endif +scx_check: +#endif /* CONFIG_RT_GROUP_SCHED */ return scx_cgroup_can_attach(tset); } @@ -9841,18 +9842,6 @@ static struct cftype cpu_legacy_files[] = { .seq_show = cpu_cfs_local_stat_show, }, #endif -#ifdef CONFIG_RT_GROUP_SCHED - { - .name = "rt_runtime_us", - .read_s64 = cpu_rt_runtime_read, - .write_s64 = cpu_rt_runtime_write, - }, - { - .name = "rt_period_us", - .read_u64 = cpu_rt_period_read_uint, - .write_u64 = cpu_rt_period_write_uint, - }, -#endif #ifdef CONFIG_UCLAMP_TASK_GROUP { .name = "uclamp.min", @@ -9870,6 +9859,55 @@ static struct cftype cpu_legacy_files[] = { { } /* Terminate */ }; +#ifdef CONFIG_RT_GROUP_SCHED +static struct cftype rt_group_files[] = { + { + .name = "rt_runtime_us", + .read_s64 = cpu_rt_runtime_read, + .write_s64 = cpu_rt_runtime_write, + }, + { + .name = "rt_period_us", + .read_u64 = cpu_rt_period_read_uint, + .write_u64 = cpu_rt_period_write_uint, + }, + { } /* Terminate */ +}; + +# ifdef CONFIG_RT_GROUP_SCHED_DEFAULT_DISABLED +DEFINE_STATIC_KEY_FALSE(rt_group_sched); +# else +DEFINE_STATIC_KEY_TRUE(rt_group_sched); +# endif + +static int __init setup_rt_group_sched(char *str) +{ + long val; + + if (kstrtol(str, 0, &val) || val < 0 || val > 1) { + pr_warn("Unable to set rt_group_sched\n"); + return 1; + } + if (val) + static_branch_enable(&rt_group_sched); + else + static_branch_disable(&rt_group_sched); + + return 1; +} +__setup("rt_group_sched=", setup_rt_group_sched); + +static int __init cpu_rt_group_init(void) +{ + if (!rt_group_sched_enabled()) + return 0; + + WARN_ON(cgroup_add_legacy_cftypes(&cpu_cgrp_subsys, rt_group_files)); + return 0; +} +subsys_initcall(cpu_rt_group_init); +#endif /* CONFIG_RT_GROUP_SCHED */ + static int cpu_extra_stat_show(struct seq_file *sf, struct cgroup_subsys_state *css) { @@ -10683,7 +10721,6 @@ void sched_mm_cid_after_execve(struct task_struct *t) smp_mb(); t->last_mm_cid = t->mm_cid = mm_cid_get(rq, t, mm); } - rseq_set_notify_resume(t); } void sched_mm_cid_fork(struct task_struct *t) |