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-rw-r--r--kernel/sched.c98
1 files changed, 66 insertions, 32 deletions
diff --git a/kernel/sched.c b/kernel/sched.c
index 1535f3884b88..3c11ae0a948d 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -309,6 +309,8 @@ static DEFINE_PER_CPU_SHARED_ALIGNED(struct rt_rq, init_rt_rq);
309 */ 309 */
310static DEFINE_SPINLOCK(task_group_lock); 310static DEFINE_SPINLOCK(task_group_lock);
311 311
312#ifdef CONFIG_FAIR_GROUP_SCHED
313
312#ifdef CONFIG_SMP 314#ifdef CONFIG_SMP
313static int root_task_group_empty(void) 315static int root_task_group_empty(void)
314{ 316{
@@ -316,7 +318,6 @@ static int root_task_group_empty(void)
316} 318}
317#endif 319#endif
318 320
319#ifdef CONFIG_FAIR_GROUP_SCHED
320#ifdef CONFIG_USER_SCHED 321#ifdef CONFIG_USER_SCHED
321# define INIT_TASK_GROUP_LOAD (2*NICE_0_LOAD) 322# define INIT_TASK_GROUP_LOAD (2*NICE_0_LOAD)
322#else /* !CONFIG_USER_SCHED */ 323#else /* !CONFIG_USER_SCHED */
@@ -676,6 +677,7 @@ inline void update_rq_clock(struct rq *rq)
676 677
677/** 678/**
678 * runqueue_is_locked 679 * runqueue_is_locked
680 * @cpu: the processor in question.
679 * 681 *
680 * Returns true if the current cpu runqueue is locked. 682 * Returns true if the current cpu runqueue is locked.
681 * This interface allows printk to be called with the runqueue lock 683 * This interface allows printk to be called with the runqueue lock
@@ -1563,11 +1565,7 @@ static unsigned long cpu_avg_load_per_task(int cpu)
1563 1565
1564#ifdef CONFIG_FAIR_GROUP_SCHED 1566#ifdef CONFIG_FAIR_GROUP_SCHED
1565 1567
1566struct update_shares_data { 1568static __read_mostly unsigned long *update_shares_data;
1567 unsigned long rq_weight[NR_CPUS];
1568};
1569
1570static DEFINE_PER_CPU(struct update_shares_data, update_shares_data);
1571 1569
1572static void __set_se_shares(struct sched_entity *se, unsigned long shares); 1570static void __set_se_shares(struct sched_entity *se, unsigned long shares);
1573 1571
@@ -1577,12 +1575,12 @@ static void __set_se_shares(struct sched_entity *se, unsigned long shares);
1577static void update_group_shares_cpu(struct task_group *tg, int cpu, 1575static void update_group_shares_cpu(struct task_group *tg, int cpu,
1578 unsigned long sd_shares, 1576 unsigned long sd_shares,
1579 unsigned long sd_rq_weight, 1577 unsigned long sd_rq_weight,
1580 struct update_shares_data *usd) 1578 unsigned long *usd_rq_weight)
1581{ 1579{
1582 unsigned long shares, rq_weight; 1580 unsigned long shares, rq_weight;
1583 int boost = 0; 1581 int boost = 0;
1584 1582
1585 rq_weight = usd->rq_weight[cpu]; 1583 rq_weight = usd_rq_weight[cpu];
1586 if (!rq_weight) { 1584 if (!rq_weight) {
1587 boost = 1; 1585 boost = 1;
1588 rq_weight = NICE_0_LOAD; 1586 rq_weight = NICE_0_LOAD;
@@ -1617,7 +1615,7 @@ static void update_group_shares_cpu(struct task_group *tg, int cpu,
1617static int tg_shares_up(struct task_group *tg, void *data) 1615static int tg_shares_up(struct task_group *tg, void *data)
1618{ 1616{
1619 unsigned long weight, rq_weight = 0, shares = 0; 1617 unsigned long weight, rq_weight = 0, shares = 0;
1620 struct update_shares_data *usd; 1618 unsigned long *usd_rq_weight;
1621 struct sched_domain *sd = data; 1619 struct sched_domain *sd = data;
1622 unsigned long flags; 1620 unsigned long flags;
1623 int i; 1621 int i;
@@ -1626,11 +1624,11 @@ static int tg_shares_up(struct task_group *tg, void *data)
1626 return 0; 1624 return 0;
1627 1625
1628 local_irq_save(flags); 1626 local_irq_save(flags);
1629 usd = &__get_cpu_var(update_shares_data); 1627 usd_rq_weight = per_cpu_ptr(update_shares_data, smp_processor_id());
1630 1628
1631 for_each_cpu(i, sched_domain_span(sd)) { 1629 for_each_cpu(i, sched_domain_span(sd)) {
1632 weight = tg->cfs_rq[i]->load.weight; 1630 weight = tg->cfs_rq[i]->load.weight;
1633 usd->rq_weight[i] = weight; 1631 usd_rq_weight[i] = weight;
1634 1632
1635 /* 1633 /*
1636 * If there are currently no tasks on the cpu pretend there 1634 * If there are currently no tasks on the cpu pretend there
@@ -1651,7 +1649,7 @@ static int tg_shares_up(struct task_group *tg, void *data)
1651 shares = tg->shares; 1649 shares = tg->shares;
1652 1650
1653 for_each_cpu(i, sched_domain_span(sd)) 1651 for_each_cpu(i, sched_domain_span(sd))
1654 update_group_shares_cpu(tg, i, shares, rq_weight, usd); 1652 update_group_shares_cpu(tg, i, shares, rq_weight, usd_rq_weight);
1655 1653
1656 local_irq_restore(flags); 1654 local_irq_restore(flags);
1657 1655
@@ -1995,6 +1993,38 @@ static inline void check_class_changed(struct rq *rq, struct task_struct *p,
1995 p->sched_class->prio_changed(rq, p, oldprio, running); 1993 p->sched_class->prio_changed(rq, p, oldprio, running);
1996} 1994}
1997 1995
1996/**
1997 * kthread_bind - bind a just-created kthread to a cpu.
1998 * @p: thread created by kthread_create().
1999 * @cpu: cpu (might not be online, must be possible) for @k to run on.
2000 *
2001 * Description: This function is equivalent to set_cpus_allowed(),
2002 * except that @cpu doesn't need to be online, and the thread must be
2003 * stopped (i.e., just returned from kthread_create()).
2004 *
2005 * Function lives here instead of kthread.c because it messes with
2006 * scheduler internals which require locking.
2007 */
2008void kthread_bind(struct task_struct *p, unsigned int cpu)
2009{
2010 struct rq *rq = cpu_rq(cpu);
2011 unsigned long flags;
2012
2013 /* Must have done schedule() in kthread() before we set_task_cpu */
2014 if (!wait_task_inactive(p, TASK_UNINTERRUPTIBLE)) {
2015 WARN_ON(1);
2016 return;
2017 }
2018
2019 spin_lock_irqsave(&rq->lock, flags);
2020 set_task_cpu(p, cpu);
2021 p->cpus_allowed = cpumask_of_cpu(cpu);
2022 p->rt.nr_cpus_allowed = 1;
2023 p->flags |= PF_THREAD_BOUND;
2024 spin_unlock_irqrestore(&rq->lock, flags);
2025}
2026EXPORT_SYMBOL(kthread_bind);
2027
1998#ifdef CONFIG_SMP 2028#ifdef CONFIG_SMP
1999/* 2029/*
2000 * Is this task likely cache-hot: 2030 * Is this task likely cache-hot:
@@ -2007,7 +2037,7 @@ task_hot(struct task_struct *p, u64 now, struct sched_domain *sd)
2007 /* 2037 /*
2008 * Buddy candidates are cache hot: 2038 * Buddy candidates are cache hot:
2009 */ 2039 */
2010 if (sched_feat(CACHE_HOT_BUDDY) && 2040 if (sched_feat(CACHE_HOT_BUDDY) && this_rq()->nr_running &&
2011 (&p->se == cfs_rq_of(&p->se)->next || 2041 (&p->se == cfs_rq_of(&p->se)->next ||
2012 &p->se == cfs_rq_of(&p->se)->last)) 2042 &p->se == cfs_rq_of(&p->se)->last))
2013 return 1; 2043 return 1;
@@ -2311,7 +2341,7 @@ static int try_to_wake_up(struct task_struct *p, unsigned int state,
2311{ 2341{
2312 int cpu, orig_cpu, this_cpu, success = 0; 2342 int cpu, orig_cpu, this_cpu, success = 0;
2313 unsigned long flags; 2343 unsigned long flags;
2314 struct rq *rq; 2344 struct rq *rq, *orig_rq;
2315 2345
2316 if (!sched_feat(SYNC_WAKEUPS)) 2346 if (!sched_feat(SYNC_WAKEUPS))
2317 wake_flags &= ~WF_SYNC; 2347 wake_flags &= ~WF_SYNC;
@@ -2319,7 +2349,7 @@ static int try_to_wake_up(struct task_struct *p, unsigned int state,
2319 this_cpu = get_cpu(); 2349 this_cpu = get_cpu();
2320 2350
2321 smp_wmb(); 2351 smp_wmb();
2322 rq = task_rq_lock(p, &flags); 2352 rq = orig_rq = task_rq_lock(p, &flags);
2323 update_rq_clock(rq); 2353 update_rq_clock(rq);
2324 if (!(p->state & state)) 2354 if (!(p->state & state))
2325 goto out; 2355 goto out;
@@ -2350,6 +2380,10 @@ static int try_to_wake_up(struct task_struct *p, unsigned int state,
2350 set_task_cpu(p, cpu); 2380 set_task_cpu(p, cpu);
2351 2381
2352 rq = task_rq_lock(p, &flags); 2382 rq = task_rq_lock(p, &flags);
2383
2384 if (rq != orig_rq)
2385 update_rq_clock(rq);
2386
2353 WARN_ON(p->state != TASK_WAKING); 2387 WARN_ON(p->state != TASK_WAKING);
2354 cpu = task_cpu(p); 2388 cpu = task_cpu(p);
2355 2389
@@ -2515,22 +2549,17 @@ void sched_fork(struct task_struct *p, int clone_flags)
2515 __sched_fork(p); 2549 __sched_fork(p);
2516 2550
2517 /* 2551 /*
2518 * Make sure we do not leak PI boosting priority to the child.
2519 */
2520 p->prio = current->normal_prio;
2521
2522 /*
2523 * Revert to default priority/policy on fork if requested. 2552 * Revert to default priority/policy on fork if requested.
2524 */ 2553 */
2525 if (unlikely(p->sched_reset_on_fork)) { 2554 if (unlikely(p->sched_reset_on_fork)) {
2526 if (p->policy == SCHED_FIFO || p->policy == SCHED_RR) 2555 if (p->policy == SCHED_FIFO || p->policy == SCHED_RR) {
2527 p->policy = SCHED_NORMAL; 2556 p->policy = SCHED_NORMAL;
2528 2557 p->normal_prio = p->static_prio;
2529 if (p->normal_prio < DEFAULT_PRIO) 2558 }
2530 p->prio = DEFAULT_PRIO;
2531 2559
2532 if (PRIO_TO_NICE(p->static_prio) < 0) { 2560 if (PRIO_TO_NICE(p->static_prio) < 0) {
2533 p->static_prio = NICE_TO_PRIO(0); 2561 p->static_prio = NICE_TO_PRIO(0);
2562 p->normal_prio = p->static_prio;
2534 set_load_weight(p); 2563 set_load_weight(p);
2535 } 2564 }
2536 2565
@@ -2541,6 +2570,11 @@ void sched_fork(struct task_struct *p, int clone_flags)
2541 p->sched_reset_on_fork = 0; 2570 p->sched_reset_on_fork = 0;
2542 } 2571 }
2543 2572
2573 /*
2574 * Make sure we do not leak PI boosting priority to the child.
2575 */
2576 p->prio = current->normal_prio;
2577
2544 if (!rt_prio(p->prio)) 2578 if (!rt_prio(p->prio))
2545 p->sched_class = &fair_sched_class; 2579 p->sched_class = &fair_sched_class;
2546 2580
@@ -2581,8 +2615,6 @@ void wake_up_new_task(struct task_struct *p, unsigned long clone_flags)
2581 BUG_ON(p->state != TASK_RUNNING); 2615 BUG_ON(p->state != TASK_RUNNING);
2582 update_rq_clock(rq); 2616 update_rq_clock(rq);
2583 2617
2584 p->prio = effective_prio(p);
2585
2586 if (!p->sched_class->task_new || !current->se.on_rq) { 2618 if (!p->sched_class->task_new || !current->se.on_rq) {
2587 activate_task(rq, p, 0); 2619 activate_task(rq, p, 0);
2588 } else { 2620 } else {
@@ -3658,6 +3690,7 @@ static void update_group_power(struct sched_domain *sd, int cpu)
3658 3690
3659/** 3691/**
3660 * update_sg_lb_stats - Update sched_group's statistics for load balancing. 3692 * update_sg_lb_stats - Update sched_group's statistics for load balancing.
3693 * @sd: The sched_domain whose statistics are to be updated.
3661 * @group: sched_group whose statistics are to be updated. 3694 * @group: sched_group whose statistics are to be updated.
3662 * @this_cpu: Cpu for which load balance is currently performed. 3695 * @this_cpu: Cpu for which load balance is currently performed.
3663 * @idle: Idle status of this_cpu 3696 * @idle: Idle status of this_cpu
@@ -6720,9 +6753,6 @@ EXPORT_SYMBOL(yield);
6720/* 6753/*
6721 * This task is about to go to sleep on IO. Increment rq->nr_iowait so 6754 * This task is about to go to sleep on IO. Increment rq->nr_iowait so
6722 * that process accounting knows that this is a task in IO wait state. 6755 * that process accounting knows that this is a task in IO wait state.
6723 *
6724 * But don't do that if it is a deliberate, throttling IO wait (this task
6725 * has set its backing_dev_info: the queue against which it should throttle)
6726 */ 6756 */
6727void __sched io_schedule(void) 6757void __sched io_schedule(void)
6728{ 6758{
@@ -9406,6 +9436,10 @@ void __init sched_init(void)
9406#endif /* CONFIG_USER_SCHED */ 9436#endif /* CONFIG_USER_SCHED */
9407#endif /* CONFIG_GROUP_SCHED */ 9437#endif /* CONFIG_GROUP_SCHED */
9408 9438
9439#if defined CONFIG_FAIR_GROUP_SCHED && defined CONFIG_SMP
9440 update_shares_data = __alloc_percpu(nr_cpu_ids * sizeof(unsigned long),
9441 __alignof__(unsigned long));
9442#endif
9409 for_each_possible_cpu(i) { 9443 for_each_possible_cpu(i) {
9410 struct rq *rq; 9444 struct rq *rq;
9411 9445
@@ -9531,13 +9565,13 @@ void __init sched_init(void)
9531 current->sched_class = &fair_sched_class; 9565 current->sched_class = &fair_sched_class;
9532 9566
9533 /* Allocate the nohz_cpu_mask if CONFIG_CPUMASK_OFFSTACK */ 9567 /* Allocate the nohz_cpu_mask if CONFIG_CPUMASK_OFFSTACK */
9534 alloc_cpumask_var(&nohz_cpu_mask, GFP_NOWAIT); 9568 zalloc_cpumask_var(&nohz_cpu_mask, GFP_NOWAIT);
9535#ifdef CONFIG_SMP 9569#ifdef CONFIG_SMP
9536#ifdef CONFIG_NO_HZ 9570#ifdef CONFIG_NO_HZ
9537 alloc_cpumask_var(&nohz.cpu_mask, GFP_NOWAIT); 9571 zalloc_cpumask_var(&nohz.cpu_mask, GFP_NOWAIT);
9538 alloc_cpumask_var(&nohz.ilb_grp_nohz_mask, GFP_NOWAIT); 9572 alloc_cpumask_var(&nohz.ilb_grp_nohz_mask, GFP_NOWAIT);
9539#endif 9573#endif
9540 alloc_cpumask_var(&cpu_isolated_map, GFP_NOWAIT); 9574 zalloc_cpumask_var(&cpu_isolated_map, GFP_NOWAIT);
9541#endif /* SMP */ 9575#endif /* SMP */
9542 9576
9543 perf_event_init(); 9577 perf_event_init();