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-rw-r--r--kernel/sched.c766
1 files changed, 409 insertions, 357 deletions
diff --git a/kernel/sched.c b/kernel/sched.c
index e7f2cfa6a257..3a8fb30a91b1 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -141,7 +141,7 @@ struct rt_prio_array {
struct rt_bandwidth {
/* nests inside the rq lock: */
- spinlock_t rt_runtime_lock;
+ raw_spinlock_t rt_runtime_lock;
ktime_t rt_period;
u64 rt_runtime;
struct hrtimer rt_period_timer;
@@ -178,7 +178,7 @@ void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime)
rt_b->rt_period = ns_to_ktime(period);
rt_b->rt_runtime = runtime;
- spin_lock_init(&rt_b->rt_runtime_lock);
+ raw_spin_lock_init(&rt_b->rt_runtime_lock);
hrtimer_init(&rt_b->rt_period_timer,
CLOCK_MONOTONIC, HRTIMER_MODE_REL);
@@ -200,7 +200,7 @@ static void start_rt_bandwidth(struct rt_bandwidth *rt_b)
if (hrtimer_active(&rt_b->rt_period_timer))
return;
- spin_lock(&rt_b->rt_runtime_lock);
+ raw_spin_lock(&rt_b->rt_runtime_lock);
for (;;) {
unsigned long delta;
ktime_t soft, hard;
@@ -217,7 +217,7 @@ static void start_rt_bandwidth(struct rt_bandwidth *rt_b)
__hrtimer_start_range_ns(&rt_b->rt_period_timer, soft, delta,
HRTIMER_MODE_ABS_PINNED, 0);
}
- spin_unlock(&rt_b->rt_runtime_lock);
+ raw_spin_unlock(&rt_b->rt_runtime_lock);
}
#ifdef CONFIG_RT_GROUP_SCHED
@@ -298,7 +298,7 @@ static DEFINE_PER_CPU_SHARED_ALIGNED(struct cfs_rq, init_tg_cfs_rq);
#ifdef CONFIG_RT_GROUP_SCHED
static DEFINE_PER_CPU(struct sched_rt_entity, init_sched_rt_entity);
-static DEFINE_PER_CPU_SHARED_ALIGNED(struct rt_rq, init_rt_rq);
+static DEFINE_PER_CPU_SHARED_ALIGNED(struct rt_rq, init_rt_rq_var);
#endif /* CONFIG_RT_GROUP_SCHED */
#else /* !CONFIG_USER_SCHED */
#define root_task_group init_task_group
@@ -470,7 +470,7 @@ struct rt_rq {
u64 rt_time;
u64 rt_runtime;
/* Nests inside the rq lock: */
- spinlock_t rt_runtime_lock;
+ raw_spinlock_t rt_runtime_lock;
#ifdef CONFIG_RT_GROUP_SCHED
unsigned long rt_nr_boosted;
@@ -525,7 +525,7 @@ static struct root_domain def_root_domain;
*/
struct rq {
/* runqueue lock: */
- spinlock_t lock;
+ raw_spinlock_t lock;
/*
* nr_running and cpu_load should be in the same cacheline because
@@ -685,7 +685,7 @@ inline void update_rq_clock(struct rq *rq)
*/
int runqueue_is_locked(int cpu)
{
- return spin_is_locked(&cpu_rq(cpu)->lock);
+ return raw_spin_is_locked(&cpu_rq(cpu)->lock);
}
/*
@@ -814,6 +814,7 @@ const_debug unsigned int sysctl_sched_nr_migrate = 32;
* default: 0.25ms
*/
unsigned int sysctl_sched_shares_ratelimit = 250000;
+unsigned int normalized_sysctl_sched_shares_ratelimit = 250000;
/*
* Inject some fuzzyness into changing the per-cpu group shares
@@ -892,7 +893,7 @@ static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev)
*/
spin_acquire(&rq->lock.dep_map, 0, 0, _THIS_IP_);
- spin_unlock_irq(&rq->lock);
+ raw_spin_unlock_irq(&rq->lock);
}
#else /* __ARCH_WANT_UNLOCKED_CTXSW */
@@ -916,9 +917,9 @@ static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next)
next->oncpu = 1;
#endif
#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
- spin_unlock_irq(&rq->lock);
+ raw_spin_unlock_irq(&rq->lock);
#else
- spin_unlock(&rq->lock);
+ raw_spin_unlock(&rq->lock);
#endif
}
@@ -948,10 +949,10 @@ static inline struct rq *__task_rq_lock(struct task_struct *p)
{
for (;;) {
struct rq *rq = task_rq(p);
- spin_lock(&rq->lock);
+ raw_spin_lock(&rq->lock);
if (likely(rq == task_rq(p)))
return rq;
- spin_unlock(&rq->lock);
+ raw_spin_unlock(&rq->lock);
}
}
@@ -968,10 +969,10 @@ static struct rq *task_rq_lock(struct task_struct *p, unsigned long *flags)
for (;;) {
local_irq_save(*flags);
rq = task_rq(p);
- spin_lock(&rq->lock);
+ raw_spin_lock(&rq->lock);
if (likely(rq == task_rq(p)))
return rq;
- spin_unlock_irqrestore(&rq->lock, *flags);
+ raw_spin_unlock_irqrestore(&rq->lock, *flags);
}
}
@@ -980,19 +981,19 @@ void task_rq_unlock_wait(struct task_struct *p)
struct rq *rq = task_rq(p);
smp_mb(); /* spin-unlock-wait is not a full memory barrier */
- spin_unlock_wait(&rq->lock);
+ raw_spin_unlock_wait(&rq->lock);
}
static void __task_rq_unlock(struct rq *rq)
__releases(rq->lock)
{
- spin_unlock(&rq->lock);
+ raw_spin_unlock(&rq->lock);
}
static inline void task_rq_unlock(struct rq *rq, unsigned long *flags)
__releases(rq->lock)
{
- spin_unlock_irqrestore(&rq->lock, *flags);
+ raw_spin_unlock_irqrestore(&rq->lock, *flags);
}
/*
@@ -1005,7 +1006,7 @@ static struct rq *this_rq_lock(void)
local_irq_disable();
rq = this_rq();
- spin_lock(&rq->lock);
+ raw_spin_lock(&rq->lock);
return rq;
}
@@ -1052,10 +1053,10 @@ static enum hrtimer_restart hrtick(struct hrtimer *timer)
WARN_ON_ONCE(cpu_of(rq) != smp_processor_id());
- spin_lock(&rq->lock);
+ raw_spin_lock(&rq->lock);
update_rq_clock(rq);
rq->curr->sched_class->task_tick(rq, rq->curr, 1);
- spin_unlock(&rq->lock);
+ raw_spin_unlock(&rq->lock);
return HRTIMER_NORESTART;
}
@@ -1068,10 +1069,10 @@ static void __hrtick_start(void *arg)
{
struct rq *rq = arg;
- spin_lock(&rq->lock);
+ raw_spin_lock(&rq->lock);
hrtimer_restart(&rq->hrtick_timer);
rq->hrtick_csd_pending = 0;
- spin_unlock(&rq->lock);
+ raw_spin_unlock(&rq->lock);
}
/*
@@ -1178,7 +1179,7 @@ static void resched_task(struct task_struct *p)
{
int cpu;
- assert_spin_locked(&task_rq(p)->lock);
+ assert_raw_spin_locked(&task_rq(p)->lock);
if (test_tsk_need_resched(p))
return;
@@ -1200,10 +1201,10 @@ static void resched_cpu(int cpu)
struct rq *rq = cpu_rq(cpu);
unsigned long flags;
- if (!spin_trylock_irqsave(&rq->lock, flags))
+ if (!raw_spin_trylock_irqsave(&rq->lock, flags))
return;
resched_task(cpu_curr(cpu));
- spin_unlock_irqrestore(&rq->lock, flags);
+ raw_spin_unlock_irqrestore(&rq->lock, flags);
}
#ifdef CONFIG_NO_HZ
@@ -1272,7 +1273,7 @@ static void sched_rt_avg_update(struct rq *rq, u64 rt_delta)
#else /* !CONFIG_SMP */
static void resched_task(struct task_struct *p)
{
- assert_spin_locked(&task_rq(p)->lock);
+ assert_raw_spin_locked(&task_rq(p)->lock);
set_tsk_need_resched(p);
}
@@ -1599,11 +1600,11 @@ static void update_group_shares_cpu(struct task_group *tg, int cpu,
struct rq *rq = cpu_rq(cpu);
unsigned long flags;
- spin_lock_irqsave(&rq->lock, flags);
+ raw_spin_lock_irqsave(&rq->lock, flags);
tg->cfs_rq[cpu]->rq_weight = boost ? 0 : rq_weight;
tg->cfs_rq[cpu]->shares = boost ? 0 : shares;
__set_se_shares(tg->se[cpu], shares);
- spin_unlock_irqrestore(&rq->lock, flags);
+ raw_spin_unlock_irqrestore(&rq->lock, flags);
}
}
@@ -1614,7 +1615,7 @@ static void update_group_shares_cpu(struct task_group *tg, int cpu,
*/
static int tg_shares_up(struct task_group *tg, void *data)
{
- unsigned long weight, rq_weight = 0, shares = 0;
+ unsigned long weight, rq_weight = 0, sum_weight = 0, shares = 0;
unsigned long *usd_rq_weight;
struct sched_domain *sd = data;
unsigned long flags;
@@ -1630,6 +1631,7 @@ static int tg_shares_up(struct task_group *tg, void *data)
weight = tg->cfs_rq[i]->load.weight;
usd_rq_weight[i] = weight;
+ rq_weight += weight;
/*
* If there are currently no tasks on the cpu pretend there
* is one of average load so that when a new task gets to
@@ -1638,10 +1640,13 @@ static int tg_shares_up(struct task_group *tg, void *data)
if (!weight)
weight = NICE_0_LOAD;
- rq_weight += weight;
+ sum_weight += weight;
shares += tg->cfs_rq[i]->shares;
}
+ if (!rq_weight)
+ rq_weight = sum_weight;
+
if ((!shares && rq_weight) || shares > tg->shares)
shares = tg->shares;
@@ -1701,9 +1706,9 @@ static void update_shares_locked(struct rq *rq, struct sched_domain *sd)
if (root_task_group_empty())
return;
- spin_unlock(&rq->lock);
+ raw_spin_unlock(&rq->lock);
update_shares(sd);
- spin_lock(&rq->lock);
+ raw_spin_lock(&rq->lock);
}
static void update_h_load(long cpu)
@@ -1743,7 +1748,7 @@ static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
__acquires(busiest->lock)
__acquires(this_rq->lock)
{
- spin_unlock(&this_rq->lock);
+ raw_spin_unlock(&this_rq->lock);
double_rq_lock(this_rq, busiest);
return 1;
@@ -1764,14 +1769,16 @@ static int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
{
int ret = 0;
- if (unlikely(!spin_trylock(&busiest->lock))) {
+ if (unlikely(!raw_spin_trylock(&busiest->lock))) {
if (busiest < this_rq) {
- spin_unlock(&this_rq->lock);
- spin_lock(&busiest->lock);
- spin_lock_nested(&this_rq->lock, SINGLE_DEPTH_NESTING);
+ raw_spin_unlock(&this_rq->lock);
+ raw_spin_lock(&busiest->lock);
+ raw_spin_lock_nested(&this_rq->lock,
+ SINGLE_DEPTH_NESTING);
ret = 1;
} else
- spin_lock_nested(&busiest->lock, SINGLE_DEPTH_NESTING);
+ raw_spin_lock_nested(&busiest->lock,
+ SINGLE_DEPTH_NESTING);
}
return ret;
}
@@ -1785,7 +1792,7 @@ static int double_lock_balance(struct rq *this_rq, struct rq *busiest)
{
if (unlikely(!irqs_disabled())) {
/* printk() doesn't work good under rq->lock */
- spin_unlock(&this_rq->lock);
+ raw_spin_unlock(&this_rq->lock);
BUG_ON(1);
}
@@ -1795,7 +1802,7 @@ static int double_lock_balance(struct rq *this_rq, struct rq *busiest)
static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest)
__releases(busiest->lock)
{
- spin_unlock(&busiest->lock);
+ raw_spin_unlock(&busiest->lock);
lock_set_subclass(&this_rq->lock.dep_map, 0, _RET_IP_);
}
#endif
@@ -1810,6 +1817,22 @@ static void cfs_rq_set_shares(struct cfs_rq *cfs_rq, unsigned long shares)
#endif
static void calc_load_account_active(struct rq *this_rq);
+static void update_sysctl(void);
+static int get_update_sysctl_factor(void);
+
+static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
+{
+ set_task_rq(p, cpu);
+#ifdef CONFIG_SMP
+ /*
+ * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be
+ * successfuly executed on another CPU. We must ensure that updates of
+ * per-task data have been completed by this moment.
+ */
+ smp_wmb();
+ task_thread_info(p)->cpu = cpu;
+#endif
+}
#include "sched_stats.h"
#include "sched_idletask.c"
@@ -1967,20 +1990,6 @@ inline int task_curr(const struct task_struct *p)
return cpu_curr(task_cpu(p)) == p;
}
-static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
-{
- set_task_rq(p, cpu);
-#ifdef CONFIG_SMP
- /*
- * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be
- * successfuly executed on another CPU. We must ensure that updates of
- * per-task data have been completed by this moment.
- */
- smp_wmb();
- task_thread_info(p)->cpu = cpu;
-#endif
-}
-
static inline void check_class_changed(struct rq *rq, struct task_struct *p,
const struct sched_class *prev_class,
int oldprio, int running)
@@ -1993,39 +2002,6 @@ static inline void check_class_changed(struct rq *rq, struct task_struct *p,
p->sched_class->prio_changed(rq, p, oldprio, running);
}
-/**
- * kthread_bind - bind a just-created kthread to a cpu.
- * @p: thread created by kthread_create().
- * @cpu: cpu (might not be online, must be possible) for @k to run on.
- *
- * Description: This function is equivalent to set_cpus_allowed(),
- * except that @cpu doesn't need to be online, and the thread must be
- * stopped (i.e., just returned from kthread_create()).
- *
- * Function lives here instead of kthread.c because it messes with
- * scheduler internals which require locking.
- */
-void kthread_bind(struct task_struct *p, unsigned int cpu)
-{
- struct rq *rq = cpu_rq(cpu);
- unsigned long flags;
-
- /* Must have done schedule() in kthread() before we set_task_cpu */
- if (!wait_task_inactive(p, TASK_UNINTERRUPTIBLE)) {
- WARN_ON(1);
- return;
- }
-
- spin_lock_irqsave(&rq->lock, flags);
- update_rq_clock(rq);
- set_task_cpu(p, cpu);
- p->cpus_allowed = cpumask_of_cpu(cpu);
- p->rt.nr_cpus_allowed = 1;
- p->flags |= PF_THREAD_BOUND;
- spin_unlock_irqrestore(&rq->lock, flags);
-}
-EXPORT_SYMBOL(kthread_bind);
-
#ifdef CONFIG_SMP
/*
* Is this task likely cache-hot:
@@ -2035,6 +2011,9 @@ task_hot(struct task_struct *p, u64 now, struct sched_domain *sd)
{
s64 delta;
+ if (p->sched_class != &fair_sched_class)
+ return 0;
+
/*
* Buddy candidates are cache hot:
*/
@@ -2043,9 +2022,6 @@ task_hot(struct task_struct *p, u64 now, struct sched_domain *sd)
&p->se == cfs_rq_of(&p->se)->last))
return 1;
- if (p->sched_class != &fair_sched_class)
- return 0;
-
if (sysctl_sched_migration_cost == -1)
return 1;
if (sysctl_sched_migration_cost == 0)
@@ -2056,38 +2032,23 @@ task_hot(struct task_struct *p, u64 now, struct sched_domain *sd)
return delta < (s64)sysctl_sched_migration_cost;
}
-
void set_task_cpu(struct task_struct *p, unsigned int new_cpu)
{
- int old_cpu = task_cpu(p);
- struct rq *old_rq = cpu_rq(old_cpu), *new_rq = cpu_rq(new_cpu);
- struct cfs_rq *old_cfsrq = task_cfs_rq(p),
- *new_cfsrq = cpu_cfs_rq(old_cfsrq, new_cpu);
- u64 clock_offset;
-
- clock_offset = old_rq->clock - new_rq->clock;
+#ifdef CONFIG_SCHED_DEBUG
+ /*
+ * We should never call set_task_cpu() on a blocked task,
+ * ttwu() will sort out the placement.
+ */
+ WARN_ON_ONCE(p->state != TASK_RUNNING && p->state != TASK_WAKING &&
+ !(task_thread_info(p)->preempt_count & PREEMPT_ACTIVE));
+#endif
trace_sched_migrate_task(p, new_cpu);
-#ifdef CONFIG_SCHEDSTATS
- if (p->se.wait_start)
- p->se.wait_start -= clock_offset;
- if (p->se.sleep_start)
- p->se.sleep_start -= clock_offset;
- if (p->se.block_start)
- p->se.block_start -= clock_offset;
-#endif
- if (old_cpu != new_cpu) {
+ if (task_cpu(p) != new_cpu) {
p->se.nr_migrations++;
-#ifdef CONFIG_SCHEDSTATS
- if (task_hot(p, old_rq->clock, NULL))
- schedstat_inc(p, se.nr_forced2_migrations);
-#endif
- perf_sw_event(PERF_COUNT_SW_CPU_MIGRATIONS,
- 1, 1, NULL, 0);
+ perf_sw_event(PERF_COUNT_SW_CPU_MIGRATIONS, 1, 1, NULL, 0);
}
- p->se.vruntime -= old_cfsrq->min_vruntime -
- new_cfsrq->min_vruntime;
__set_task_cpu(p, new_cpu);
}
@@ -2112,13 +2073,10 @@ migrate_task(struct task_struct *p, int dest_cpu, struct migration_req *req)
/*
* If the task is not on a runqueue (and not running), then
- * it is sufficient to simply update the task's cpu field.
+ * the next wake-up will properly place the task.
*/
- if (!p->se.on_rq && !task_running(rq, p)) {
- update_rq_clock(rq);
- set_task_cpu(p, dest_cpu);
+ if (!p->se.on_rq && !task_running(rq, p))
return 0;
- }
init_completion(&req->done);
req->task = p;
@@ -2323,6 +2281,75 @@ void task_oncpu_function_call(struct task_struct *p,
preempt_enable();
}
+#ifdef CONFIG_SMP
+static int select_fallback_rq(int cpu, struct task_struct *p)
+{
+ int dest_cpu;
+ const struct cpumask *nodemask = cpumask_of_node(cpu_to_node(cpu));
+
+ /* Look for allowed, online CPU in same node. */
+ for_each_cpu_and(dest_cpu, nodemask, cpu_active_mask)
+ if (cpumask_test_cpu(dest_cpu, &p->cpus_allowed))
+ return dest_cpu;
+
+ /* Any allowed, online CPU? */
+ dest_cpu = cpumask_any_and(&p->cpus_allowed, cpu_active_mask);
+ if (dest_cpu < nr_cpu_ids)
+ return dest_cpu;
+
+ /* No more Mr. Nice Guy. */
+ if (dest_cpu >= nr_cpu_ids) {
+ rcu_read_lock();
+ cpuset_cpus_allowed_locked(p, &p->cpus_allowed);
+ rcu_read_unlock();
+ dest_cpu = cpumask_any_and(cpu_active_mask, &p->cpus_allowed);
+
+ /*
+ * Don't tell them about moving exiting tasks or
+ * kernel threads (both mm NULL), since they never
+ * leave kernel.
+ */
+ if (p->mm && printk_ratelimit()) {
+ printk(KERN_INFO "process %d (%s) no "
+ "longer affine to cpu%d\n",
+ task_pid_nr(p), p->comm, cpu);
+ }
+ }
+
+ return dest_cpu;
+}
+
+/*
+ * Gets called from 3 sites (exec, fork, wakeup), since it is called without
+ * holding rq->lock we need to ensure ->cpus_allowed is stable, this is done
+ * by:
+ *
+ * exec: is unstable, retry loop
+ * fork & wake-up: serialize ->cpus_allowed against TASK_WAKING
+ */
+static inline
+int select_task_rq(struct task_struct *p, int sd_flags, int wake_flags)
+{
+ int cpu = p->sched_class->select_task_rq(p, sd_flags, wake_flags);
+
+ /*
+ * In order not to call set_task_cpu() on a blocking task we need
+ * to rely on ttwu() to place the task on a valid ->cpus_allowed
+ * cpu.
+ *
+ * Since this is common to all placement strategies, this lives here.
+ *
+ * [ this allows ->select_task() to simply return task_cpu(p) and
+ * not worry about this generic constraint ]
+ */
+ if (unlikely(!cpumask_test_cpu(cpu, &p->cpus_allowed) ||
+ !cpu_online(cpu)))
+ cpu = select_fallback_rq(task_cpu(p), p);
+
+ return cpu;
+}
+#endif
+
/***
* try_to_wake_up - wake up a thread
* @p: the to-be-woken-up thread
@@ -2374,17 +2401,18 @@ static int try_to_wake_up(struct task_struct *p, unsigned int state,
if (task_contributes_to_load(p))
rq->nr_uninterruptible--;
p->state = TASK_WAKING;
- task_rq_unlock(rq, &flags);
- cpu = p->sched_class->select_task_rq(p, SD_BALANCE_WAKE, wake_flags);
- if (cpu != orig_cpu) {
- local_irq_save(flags);
- rq = cpu_rq(cpu);
- update_rq_clock(rq);
+ if (p->sched_class->task_waking)
+ p->sched_class->task_waking(rq, p);
+
+ __task_rq_unlock(rq);
+
+ cpu = select_task_rq(p, SD_BALANCE_WAKE, wake_flags);
+ if (cpu != orig_cpu)
set_task_cpu(p, cpu);
- local_irq_restore(flags);
- }
- rq = task_rq_lock(p, &flags);
+
+ rq = __task_rq_lock(p);
+ update_rq_clock(rq);
WARN_ON(p->state != TASK_WAKING);
cpu = task_cpu(p);
@@ -2440,8 +2468,8 @@ out_running:
p->state = TASK_RUNNING;
#ifdef CONFIG_SMP
- if (p->sched_class->task_wake_up)
- p->sched_class->task_wake_up(rq, p);
+ if (p->sched_class->task_woken)
+ p->sched_class->task_woken(rq, p);
if (unlikely(rq->idle_stamp)) {
u64 delta = rq->clock - rq->idle_stamp;
@@ -2499,7 +2527,6 @@ static void __sched_fork(struct task_struct *p)
p->se.avg_overlap = 0;
p->se.start_runtime = 0;
p->se.avg_wakeup = sysctl_sched_wakeup_granularity;
- p->se.avg_running = 0;
#ifdef CONFIG_SCHEDSTATS
p->se.wait_start = 0;
@@ -2521,7 +2548,6 @@ static void __sched_fork(struct task_struct *p)
p->se.nr_failed_migrations_running = 0;
p->se.nr_failed_migrations_hot = 0;
p->se.nr_forced_migrations = 0;
- p->se.nr_forced2_migrations = 0;
p->se.nr_wakeups = 0;
p->se.nr_wakeups_sync = 0;
@@ -2542,14 +2568,6 @@ static void __sched_fork(struct task_struct *p)
#ifdef CONFIG_PREEMPT_NOTIFIERS
INIT_HLIST_HEAD(&p->preempt_notifiers);
#endif
-
- /*
- * We mark the process as running here, but have not actually
- * inserted it onto the runqueue yet. This guarantees that
- * nobody will actually run it, and a signal or other external
- * event cannot wake it up and insert it on the runqueue either.
- */
- p->state = TASK_RUNNING;
}
/*
@@ -2558,9 +2576,14 @@ static void __sched_fork(struct task_struct *p)
void sched_fork(struct task_struct *p, int clone_flags)
{
int cpu = get_cpu();
- unsigned long flags;
__sched_fork(p);
+ /*
+ * We mark the process as waking here. This guarantees that
+ * nobody will actually run it, and a signal or other external
+ * event cannot wake it up and insert it on the runqueue either.
+ */
+ p->state = TASK_WAKING;
/*
* Revert to default priority/policy on fork if requested.
@@ -2592,13 +2615,10 @@ void sched_fork(struct task_struct *p, int clone_flags)
if (!rt_prio(p->prio))
p->sched_class = &fair_sched_class;
-#ifdef CONFIG_SMP
- cpu = p->sched_class->select_task_rq(p, SD_BALANCE_FORK, 0);
-#endif
- local_irq_save(flags);
- update_rq_clock(cpu_rq(cpu));
+ if (p->sched_class->task_fork)
+ p->sched_class->task_fork(p);
+
set_task_cpu(p, cpu);
- local_irq_restore(flags);
#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
if (likely(sched_info_on()))
@@ -2627,28 +2647,35 @@ void wake_up_new_task(struct task_struct *p, unsigned long clone_flags)
{
unsigned long flags;
struct rq *rq;
+ int cpu = get_cpu();
+
+#ifdef CONFIG_SMP
+ /*
+ * Fork balancing, do it here and not earlier because:
+ * - cpus_allowed can change in the fork path
+ * - any previously selected cpu might disappear through hotplug
+ *
+ * We still have TASK_WAKING but PF_STARTING is gone now, meaning
+ * ->cpus_allowed is stable, we have preemption disabled, meaning
+ * cpu_online_mask is stable.
+ */
+ cpu = select_task_rq(p, SD_BALANCE_FORK, 0);
+ set_task_cpu(p, cpu);
+#endif
rq = task_rq_lock(p, &flags);
- BUG_ON(p->state != TASK_RUNNING);
+ BUG_ON(p->state != TASK_WAKING);
+ p->state = TASK_RUNNING;
update_rq_clock(rq);
-
- if (!p->sched_class->task_new || !current->se.on_rq) {
- activate_task(rq, p, 0);
- } else {
- /*
- * Let the scheduling class do new task startup
- * management (if any):
- */
- p->sched_class->task_new(rq, p);
- inc_nr_running(rq);
- }
+ activate_task(rq, p, 0);
trace_sched_wakeup_new(rq, p, 1);
check_preempt_curr(rq, p, WF_FORK);
#ifdef CONFIG_SMP
- if (p->sched_class->task_wake_up)
- p->sched_class->task_wake_up(rq, p);
+ if (p->sched_class->task_woken)
+ p->sched_class->task_woken(rq, p);
#endif
task_rq_unlock(rq, &flags);
+ put_cpu();
}
#ifdef CONFIG_PREEMPT_NOTIFIERS
@@ -2798,10 +2825,10 @@ static inline void post_schedule(struct rq *rq)
if (rq->post_schedule) {
unsigned long flags;
- spin_lock_irqsave(&rq->lock, flags);
+ raw_spin_lock_irqsave(&rq->lock, flags);
if (rq->curr->sched_class->post_schedule)
rq->curr->sched_class->post_schedule(rq);
- spin_unlock_irqrestore(&rq->lock, flags);
+ raw_spin_unlock_irqrestore(&rq->lock, flags);
rq->post_schedule = 0;
}
@@ -3083,15 +3110,15 @@ static void double_rq_lock(struct rq *rq1, struct rq *rq2)
{
BUG_ON(!irqs_disabled());
if (rq1 == rq2) {
- spin_lock(&rq1->lock);
+ raw_spin_lock(&rq1->lock);
__acquire(rq2->lock); /* Fake it out ;) */
} else {
if (rq1 < rq2) {
- spin_lock(&rq1->lock);
- spin_lock_nested(&rq2->lock, SINGLE_DEPTH_NESTING);
+ raw_spin_lock(&rq1->lock);
+ raw_spin_lock_nested(&rq2->lock, SINGLE_DEPTH_NESTING);
} else {
- spin_lock(&rq2->lock);
- spin_lock_nested(&rq1->lock, SINGLE_DEPTH_NESTING);
+ raw_spin_lock(&rq2->lock);
+ raw_spin_lock_nested(&rq1->lock, SINGLE_DEPTH_NESTING);
}
}
update_rq_clock(rq1);
@@ -3108,29 +3135,44 @@ static void double_rq_unlock(struct rq *rq1, struct rq *rq2)
__releases(rq1->lock)
__releases(rq2->lock)
{
- spin_unlock(&rq1->lock);
+ raw_spin_unlock(&rq1->lock);
if (rq1 != rq2)
- spin_unlock(&rq2->lock);
+ raw_spin_unlock(&rq2->lock);
else
__release(rq2->lock);
}
/*
- * If dest_cpu is allowed for this process, migrate the task to it.
- * This is accomplished by forcing the cpu_allowed mask to only
- * allow dest_cpu, which will force the cpu onto dest_cpu. Then
- * the cpu_allowed mask is restored.
+ * sched_exec - execve() is a valuable balancing opportunity, because at
+ * this point the task has the smallest effective memory and cache footprint.
*/
-static void sched_migrate_task(struct task_struct *p, int dest_cpu)
+void sched_exec(void)
{
+ struct task_struct *p = current;
struct migration_req req;
+ int dest_cpu, this_cpu;
unsigned long flags;
struct rq *rq;
+again:
+ this_cpu = get_cpu();
+ dest_cpu = select_task_rq(p, SD_BALANCE_EXEC, 0);
+ if (dest_cpu == this_cpu) {
+ put_cpu();
+ return;
+ }
+
rq = task_rq_lock(p, &flags);
+ put_cpu();
+
+ /*
+ * select_task_rq() can race against ->cpus_allowed
+ */
if (!cpumask_test_cpu(dest_cpu, &p->cpus_allowed)
- || unlikely(!cpu_active(dest_cpu)))
- goto out;
+ || unlikely(!cpu_active(dest_cpu))) {
+ task_rq_unlock(rq, &flags);
+ goto again;
+ }
/* force the process onto the specified CPU */
if (migrate_task(p, dest_cpu, &req)) {
@@ -3145,24 +3187,10 @@ static void sched_migrate_task(struct task_struct *p, int dest_cpu)
return;
}
-out:
task_rq_unlock(rq, &flags);
}
/*
- * sched_exec - execve() is a valuable balancing opportunity, because at
- * this point the task has the smallest effective memory and cache footprint.
- */
-void sched_exec(void)
-{
- int new_cpu, this_cpu = get_cpu();
- new_cpu = current->sched_class->select_task_rq(current, SD_BALANCE_EXEC, 0);
- put_cpu();
- if (new_cpu != this_cpu)
- sched_migrate_task(current, new_cpu);
-}
-
-/*
* pull_task - move a task from a remote runqueue to the local runqueue.
* Both runqueues must be locked.
*/
@@ -3172,10 +3200,6 @@ static void pull_task(struct rq *src_rq, struct task_struct *p,
deactivate_task(src_rq, p, 0);
set_task_cpu(p, this_cpu);
activate_task(this_rq, p, 0);
- /*
- * Note that idle threads have a prio of MAX_PRIO, for this test
- * to be always true for them.
- */
check_preempt_curr(this_rq, p, 0);
}
@@ -4134,7 +4158,7 @@ static int load_balance(int this_cpu, struct rq *this_rq,
unsigned long flags;
struct cpumask *cpus = __get_cpu_var(load_balance_tmpmask);
- cpumask_copy(cpus, cpu_online_mask);
+ cpumask_copy(cpus, cpu_active_mask);
/*
* When power savings policy is enabled for the parent domain, idle
@@ -4207,14 +4231,15 @@ redo:
if (unlikely(sd->nr_balance_failed > sd->cache_nice_tries+2)) {
- spin_lock_irqsave(&busiest->lock, flags);
+ raw_spin_lock_irqsave(&busiest->lock, flags);
/* don't kick the migration_thread, if the curr
* task on busiest cpu can't be moved to this_cpu
*/
if (!cpumask_test_cpu(this_cpu,
&busiest->curr->cpus_allowed)) {
- spin_unlock_irqrestore(&busiest->lock, flags);
+ raw_spin_unlock_irqrestore(&busiest->lock,
+ flags);
all_pinned = 1;
goto out_one_pinned;
}
@@ -4224,7 +4249,7 @@ redo:
busiest->push_cpu = this_cpu;
active_balance = 1;
}
- spin_unlock_irqrestore(&busiest->lock, flags);
+ raw_spin_unlock_irqrestore(&busiest->lock, flags);
if (active_balance)
wake_up_process(busiest->migration_thread);
@@ -4297,7 +4322,7 @@ load_balance_newidle(int this_cpu, struct rq *this_rq, struct sched_domain *sd)
int all_pinned = 0;
struct cpumask *cpus = __get_cpu_var(load_balance_tmpmask);
- cpumask_copy(cpus, cpu_online_mask);
+ cpumask_copy(cpus, cpu_active_mask);
/*
* When power savings policy is enabled for the parent domain, idle
@@ -4406,10 +4431,10 @@ redo:
/*
* Should not call ttwu while holding a rq->lock
*/
- spin_unlock(&this_rq->lock);
+ raw_spin_unlock(&this_rq->lock);
if (active_balance)
wake_up_process(busiest->migration_thread);
- spin_lock(&this_rq->lock);
+ raw_spin_lock(&this_rq->lock);
} else
sd->nr_balance_failed = 0;
@@ -4694,7 +4719,7 @@ int select_nohz_load_balancer(int stop_tick)
cpumask_set_cpu(cpu, nohz.cpu_mask);
/* time for ilb owner also to sleep */
- if (cpumask_weight(nohz.cpu_mask) == num_online_cpus()) {
+ if (cpumask_weight(nohz.cpu_mask) == num_active_cpus()) {
if (atomic_read(&nohz.load_balancer) == cpu)
atomic_set(&nohz.load_balancer, -1);
return 0;
@@ -5278,11 +5303,11 @@ void scheduler_tick(void)
sched_clock_tick();
- spin_lock(&rq->lock);
+ raw_spin_lock(&rq->lock);
update_rq_clock(rq);
update_cpu_load(rq);
curr->sched_class->task_tick(rq, curr, 0);
- spin_unlock(&rq->lock);
+ raw_spin_unlock(&rq->lock);
perf_event_task_tick(curr, cpu);
@@ -5396,13 +5421,14 @@ static inline void schedule_debug(struct task_struct *prev)
#endif
}
-static void put_prev_task(struct rq *rq, struct task_struct *p)
+static void put_prev_task(struct rq *rq, struct task_struct *prev)
{
- u64 runtime = p->se.sum_exec_runtime - p->se.prev_sum_exec_runtime;
+ if (prev->state == TASK_RUNNING) {
+ u64 runtime = prev->se.sum_exec_runtime;
- update_avg(&p->se.avg_running, runtime);
+ runtime -= prev->se.prev_sum_exec_runtime;
+ runtime = min_t(u64, runtime, 2*sysctl_sched_migration_cost);
- if (p->state == TASK_RUNNING) {
/*
* In order to avoid avg_overlap growing stale when we are
* indeed overlapping and hence not getting put to sleep, grow
@@ -5412,12 +5438,9 @@ static void put_prev_task(struct rq *rq, struct task_struct *p)
* correlates to the amount of cache footprint a task can
* build up.
*/
- runtime = min_t(u64, runtime, 2*sysctl_sched_migration_cost);
- update_avg(&p->se.avg_overlap, runtime);
- } else {
- update_avg(&p->se.avg_running, 0);
+ update_avg(&prev->se.avg_overlap, runtime);
}
- p->sched_class->put_prev_task(rq, p);
+ prev->sched_class->put_prev_task(rq, prev);
}
/*
@@ -5478,7 +5501,7 @@ need_resched_nonpreemptible:
if (sched_feat(HRTICK))
hrtick_clear(rq);
- spin_lock_irq(&rq->lock);
+ raw_spin_lock_irq(&rq->lock);
update_rq_clock(rq);
clear_tsk_need_resched(prev);
@@ -5514,12 +5537,15 @@ need_resched_nonpreemptible:
cpu = smp_processor_id();
rq = cpu_rq(cpu);
} else
- spin_unlock_irq(&rq->lock);
+ raw_spin_unlock_irq(&rq->lock);
post_schedule(rq);
- if (unlikely(reacquire_kernel_lock(current) < 0))
+ if (unlikely(reacquire_kernel_lock(current) < 0)) {
+ prev = rq->curr;
+ switch_count = &prev->nivcsw;
goto need_resched_nonpreemptible;
+ }
preempt_enable_no_resched();
if (need_resched())
@@ -5931,14 +5957,15 @@ EXPORT_SYMBOL(wait_for_completion_killable);
*/
bool try_wait_for_completion(struct completion *x)
{
+ unsigned long flags;
int ret = 1;
- spin_lock_irq(&x->wait.lock);
+ spin_lock_irqsave(&x->wait.lock, flags);
if (!x->done)
ret = 0;
else
x->done--;
- spin_unlock_irq(&x->wait.lock);
+ spin_unlock_irqrestore(&x->wait.lock, flags);
return ret;
}
EXPORT_SYMBOL(try_wait_for_completion);
@@ -5953,12 +5980,13 @@ EXPORT_SYMBOL(try_wait_for_completion);
*/
bool completion_done(struct completion *x)
{
+ unsigned long flags;
int ret = 1;
- spin_lock_irq(&x->wait.lock);
+ spin_lock_irqsave(&x->wait.lock, flags);
if (!x->done)
ret = 0;
- spin_unlock_irq(&x->wait.lock);
+ spin_unlock_irqrestore(&x->wait.lock, flags);
return ret;
}
EXPORT_SYMBOL(completion_done);
@@ -6343,7 +6371,7 @@ recheck:
* make sure no PI-waiters arrive (or leave) while we are
* changing the priority of the task:
*/
- spin_lock_irqsave(&p->pi_lock, flags);
+ raw_spin_lock_irqsave(&p->pi_lock, flags);
/*
* To be able to change p->policy safely, the apropriate
* runqueue lock must be held.
@@ -6353,7 +6381,7 @@ recheck:
if (unlikely(oldpolicy != -1 && oldpolicy != p->policy)) {
policy = oldpolicy = -1;
__task_rq_unlock(rq);
- spin_unlock_irqrestore(&p->pi_lock, flags);
+ raw_spin_unlock_irqrestore(&p->pi_lock, flags);
goto recheck;
}
update_rq_clock(rq);
@@ -6377,7 +6405,7 @@ recheck:
check_class_changed(rq, p, prev_class, oldprio, running);
}
__task_rq_unlock(rq);
- spin_unlock_irqrestore(&p->pi_lock, flags);
+ raw_spin_unlock_irqrestore(&p->pi_lock, flags);
rt_mutex_adjust_pi(p);
@@ -6477,7 +6505,7 @@ SYSCALL_DEFINE1(sched_getscheduler, pid_t, pid)
return -EINVAL;
retval = -ESRCH;
- read_lock(&tasklist_lock);
+ rcu_read_lock();
p = find_process_by_pid(pid);
if (p) {
retval = security_task_getscheduler(p);
@@ -6485,7 +6513,7 @@ SYSCALL_DEFINE1(sched_getscheduler, pid_t, pid)
retval = p->policy
| (p->sched_reset_on_fork ? SCHED_RESET_ON_FORK : 0);
}
- read_unlock(&tasklist_lock);
+ rcu_read_unlock();
return retval;
}
@@ -6503,7 +6531,7 @@ SYSCALL_DEFINE2(sched_getparam, pid_t, pid, struct sched_param __user *, param)
if (!param || pid < 0)
return -EINVAL;
- read_lock(&tasklist_lock);
+ rcu_read_lock();
p = find_process_by_pid(pid);
retval = -ESRCH;
if (!p)
@@ -6514,7 +6542,7 @@ SYSCALL_DEFINE2(sched_getparam, pid_t, pid, struct sched_param __user *, param)
goto out_unlock;
lp.sched_priority = p->rt_priority;
- read_unlock(&tasklist_lock);
+ rcu_read_unlock();
/*
* This one might sleep, we cannot do it with a spinlock held ...
@@ -6524,7 +6552,7 @@ SYSCALL_DEFINE2(sched_getparam, pid_t, pid, struct sched_param __user *, param)
return retval;
out_unlock:
- read_unlock(&tasklist_lock);
+ rcu_read_unlock();
return retval;
}
@@ -6535,22 +6563,18 @@ long sched_setaffinity(pid_t pid, const struct cpumask *in_mask)
int retval;
get_online_cpus();
- read_lock(&tasklist_lock);
+ rcu_read_lock();
p = find_process_by_pid(pid);
if (!p) {
- read_unlock(&tasklist_lock);
+ rcu_read_unlock();
put_online_cpus();
return -ESRCH;
}
- /*
- * It is not safe to call set_cpus_allowed with the
- * tasklist_lock held. We will bump the task_struct's
- * usage count and then drop tasklist_lock.
- */
+ /* Prevent p going away */
get_task_struct(p);
- read_unlock(&tasklist_lock);
+ rcu_read_unlock();
if (!alloc_cpumask_var(&cpus_allowed, GFP_KERNEL)) {
retval = -ENOMEM;
@@ -6631,10 +6655,12 @@ SYSCALL_DEFINE3(sched_setaffinity, pid_t, pid, unsigned int, len,
long sched_getaffinity(pid_t pid, struct cpumask *mask)
{
struct task_struct *p;
+ unsigned long flags;
+ struct rq *rq;
int retval;
get_online_cpus();
- read_lock(&tasklist_lock);
+ rcu_read_lock();
retval = -ESRCH;
p = find_process_by_pid(pid);
@@ -6645,10 +6671,12 @@ long sched_getaffinity(pid_t pid, struct cpumask *mask)
if (retval)
goto out_unlock;
+ rq = task_rq_lock(p, &flags);
cpumask_and(mask, &p->cpus_allowed, cpu_online_mask);
+ task_rq_unlock(rq, &flags);
out_unlock:
- read_unlock(&tasklist_lock);
+ rcu_read_unlock();
put_online_cpus();
return retval;
@@ -6703,7 +6731,7 @@ SYSCALL_DEFINE0(sched_yield)
*/
__release(rq->lock);
spin_release(&rq->lock.dep_map, 1, _THIS_IP_);
- _raw_spin_unlock(&rq->lock);
+ do_raw_spin_unlock(&rq->lock);
preempt_enable_no_resched();
schedule();
@@ -6883,6 +6911,8 @@ SYSCALL_DEFINE2(sched_rr_get_interval, pid_t, pid,
{
struct task_struct *p;
unsigned int time_slice;
+ unsigned long flags;
+ struct rq *rq;
int retval;
struct timespec t;
@@ -6890,7 +6920,7 @@ SYSCALL_DEFINE2(sched_rr_get_interval, pid_t, pid,
return -EINVAL;
retval = -ESRCH;
- read_lock(&tasklist_lock);
+ rcu_read_lock();
p = find_process_by_pid(pid);
if (!p)
goto out_unlock;
@@ -6899,15 +6929,17 @@ SYSCALL_DEFINE2(sched_rr_get_interval, pid_t, pid,
if (retval)
goto out_unlock;
- time_slice = p->sched_class->get_rr_interval(p);
+ rq = task_rq_lock(p, &flags);
+ time_slice = p->sched_class->get_rr_interval(rq, p);
+ task_rq_unlock(rq, &flags);
- read_unlock(&tasklist_lock);
+ rcu_read_unlock();
jiffies_to_timespec(time_slice, &t);
retval = copy_to_user(interval, &t, sizeof(t)) ? -EFAULT : 0;
return retval;
out_unlock:
- read_unlock(&tasklist_lock);
+ rcu_read_unlock();
return retval;
}
@@ -6995,12 +7027,12 @@ void __cpuinit init_idle(struct task_struct *idle, int cpu)
struct rq *rq = cpu_rq(cpu);
unsigned long flags;
- spin_lock_irqsave(&rq->lock, flags);
+ raw_spin_lock_irqsave(&rq->lock, flags);
__sched_fork(idle);
+ idle->state = TASK_RUNNING;
idle->se.exec_start = sched_clock();
- idle->prio = idle->normal_prio = MAX_PRIO;
cpumask_copy(&idle->cpus_allowed, cpumask_of(cpu));
__set_task_cpu(idle, cpu);
@@ -7008,7 +7040,7 @@ void __cpuinit init_idle(struct task_struct *idle, int cpu)
#if defined(CONFIG_SMP) && defined(__ARCH_WANT_UNLOCKED_CTXSW)
idle->oncpu = 1;
#endif
- spin_unlock_irqrestore(&rq->lock, flags);
+ raw_spin_unlock_irqrestore(&rq->lock, flags);
/* Set the preempt count _outside_ the spinlocks! */
#if defined(CONFIG_PREEMPT)
@@ -7041,22 +7073,43 @@ cpumask_var_t nohz_cpu_mask;
*
* This idea comes from the SD scheduler of Con Kolivas:
*/
-static inline void sched_init_granularity(void)
+static int get_update_sysctl_factor(void)
{
- unsigned int factor = 1 + ilog2(num_online_cpus());
- const unsigned long limit = 200000000;
+ unsigned int cpus = min_t(int, num_online_cpus(), 8);
+ unsigned int factor;
- sysctl_sched_min_granularity *= factor;
- if (sysctl_sched_min_granularity > limit)
- sysctl_sched_min_granularity = limit;
+ switch (sysctl_sched_tunable_scaling) {
+ case SCHED_TUNABLESCALING_NONE:
+ factor = 1;
+ break;
+ case SCHED_TUNABLESCALING_LINEAR:
+ factor = cpus;
+ break;
+ case SCHED_TUNABLESCALING_LOG:
+ default:
+ factor = 1 + ilog2(cpus);
+ break;
+ }
- sysctl_sched_latency *= factor;
- if (sysctl_sched_latency > limit)
- sysctl_sched_latency = limit;
+ return factor;
+}
- sysctl_sched_wakeup_granularity *= factor;
+static void update_sysctl(void)
+{
+ unsigned int factor = get_update_sysctl_factor();
- sysctl_sched_shares_ratelimit *= factor;
+#define SET_SYSCTL(name) \
+ (sysctl_##name = (factor) * normalized_sysctl_##name)
+ SET_SYSCTL(sched_min_granularity);
+ SET_SYSCTL(sched_latency);
+ SET_SYSCTL(sched_wakeup_granularity);
+ SET_SYSCTL(sched_shares_ratelimit);
+#undef SET_SYSCTL
+}
+
+static inline void sched_init_granularity(void)
+{
+ update_sysctl();
}
#ifdef CONFIG_SMP
@@ -7092,8 +7145,28 @@ int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask)
struct rq *rq;
int ret = 0;
+ /*
+ * Since we rely on wake-ups to migrate sleeping tasks, don't change
+ * the ->cpus_allowed mask from under waking tasks, which would be
+ * possible when we change rq->lock in ttwu(), so synchronize against
+ * TASK_WAKING to avoid that.
+ *
+ * Make an exception for freshly cloned tasks, since cpuset namespaces
+ * might move the task about, we have to validate the target in
+ * wake_up_new_task() anyway since the cpu might have gone away.
+ */
+again:
+ while (p->state == TASK_WAKING && !(p->flags & PF_STARTING))
+ cpu_relax();
+
rq = task_rq_lock(p, &flags);
- if (!cpumask_intersects(new_mask, cpu_online_mask)) {
+
+ if (p->state == TASK_WAKING && !(p->flags & PF_STARTING)) {
+ task_rq_unlock(rq, &flags);
+ goto again;
+ }
+
+ if (!cpumask_intersects(new_mask, cpu_active_mask)) {
ret = -EINVAL;
goto out;
}
@@ -7115,7 +7188,7 @@ int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask)
if (cpumask_test_cpu(task_cpu(p), new_mask))
goto out;
- if (migrate_task(p, cpumask_any_and(cpu_online_mask, new_mask), &req)) {
+ if (migrate_task(p, cpumask_any_and(cpu_active_mask, new_mask), &req)) {
/* Need help from migration thread: drop lock and wait. */
struct task_struct *mt = rq->migration_thread;
@@ -7148,7 +7221,7 @@ EXPORT_SYMBOL_GPL(set_cpus_allowed_ptr);
static int __migrate_task(struct task_struct *p, int src_cpu, int dest_cpu)
{
struct rq *rq_dest, *rq_src;
- int ret = 0, on_rq;
+ int ret = 0;
if (unlikely(!cpu_active(dest_cpu)))
return ret;
@@ -7164,12 +7237,13 @@ static int __migrate_task(struct task_struct *p, int src_cpu, int dest_cpu)
if (!cpumask_test_cpu(dest_cpu, &p->cpus_allowed))
goto fail;
- on_rq = p->se.on_rq;
- if (on_rq)
+ /*
+ * If we're not on a rq, the next wake-up will ensure we're
+ * placed properly.
+ */
+ if (p->se.on_rq) {
deactivate_task(rq_src, p, 0);
-
- set_task_cpu(p, dest_cpu);
- if (on_rq) {
+ set_task_cpu(p, dest_cpu);
activate_task(rq_dest, p, 0);
check_preempt_curr(rq_dest, p, 0);
}
@@ -7204,10 +7278,10 @@ static int migration_thread(void *data)
struct migration_req *req;
struct list_head *head;
- spin_lock_irq(&rq->lock);
+ raw_spin_lock_irq(&rq->lock);
if (cpu_is_offline(cpu)) {
- spin_unlock_irq(&rq->lock);
+ raw_spin_unlock_irq(&rq->lock);
break;
}
@@ -7219,7 +7293,7 @@ static int migration_thread(void *data)
head = &rq->migration_queue;
if (list_empty(head)) {
- spin_unlock_irq(&rq->lock);
+ raw_spin_unlock_irq(&rq->lock);
schedule();
set_current_state(TASK_INTERRUPTIBLE);
continue;
@@ -7228,14 +7302,14 @@ static int migration_thread(void *data)
list_del_init(head->next);
if (req->task != NULL) {
- spin_unlock(&rq->lock);
+ raw_spin_unlock(&rq->lock);
__migrate_task(req->task, cpu, req->dest_cpu);
} else if (likely(cpu == (badcpu = smp_processor_id()))) {
req->dest_cpu = RCU_MIGRATION_GOT_QS;
- spin_unlock(&rq->lock);
+ raw_spin_unlock(&rq->lock);
} else {
req->dest_cpu = RCU_MIGRATION_MUST_SYNC;
- spin_unlock(&rq->lock);
+ raw_spin_unlock(&rq->lock);
WARN_ONCE(1, "migration_thread() on CPU %d, expected %d\n", badcpu, cpu);
}
local_irq_enable();
@@ -7265,37 +7339,10 @@ static int __migrate_task_irq(struct task_struct *p, int src_cpu, int dest_cpu)
static void move_task_off_dead_cpu(int dead_cpu, struct task_struct *p)
{
int dest_cpu;
- const struct cpumask *nodemask = cpumask_of_node(cpu_to_node(dead_cpu));
again:
- /* Look for allowed, online CPU in same node. */
- for_each_cpu_and(dest_cpu, nodemask, cpu_online_mask)
- if (cpumask_test_cpu(dest_cpu, &p->cpus_allowed))
- goto move;
-
- /* Any allowed, online CPU? */
- dest_cpu = cpumask_any_and(&p->cpus_allowed, cpu_online_mask);
- if (dest_cpu < nr_cpu_ids)
- goto move;
-
- /* No more Mr. Nice Guy. */
- if (dest_cpu >= nr_cpu_ids) {
- cpuset_cpus_allowed_locked(p, &p->cpus_allowed);
- dest_cpu = cpumask_any_and(cpu_online_mask, &p->cpus_allowed);
-
- /*
- * Don't tell them about moving exiting tasks or
- * kernel threads (both mm NULL), since they never
- * leave kernel.
- */
- if (p->mm && printk_ratelimit()) {
- printk(KERN_INFO "process %d (%s) no "
- "longer affine to cpu%d\n",
- task_pid_nr(p), p->comm, dead_cpu);
- }
- }
+ dest_cpu = select_fallback_rq(dead_cpu, p);
-move:
/* It can have affinity changed while we were choosing. */
if (unlikely(!__migrate_task_irq(p, dead_cpu, dest_cpu)))
goto again;
@@ -7310,7 +7357,7 @@ move:
*/
static void migrate_nr_uninterruptible(struct rq *rq_src)
{
- struct rq *rq_dest = cpu_rq(cpumask_any(cpu_online_mask));
+ struct rq *rq_dest = cpu_rq(cpumask_any(cpu_active_mask));
unsigned long flags;
local_irq_save(flags);
@@ -7358,14 +7405,14 @@ void sched_idle_next(void)
* Strictly not necessary since rest of the CPUs are stopped by now
* and interrupts disabled on the current cpu.
*/
- spin_lock_irqsave(&rq->lock, flags);
+ raw_spin_lock_irqsave(&rq->lock, flags);
__setscheduler(rq, p, SCHED_FIFO, MAX_RT_PRIO-1);
update_rq_clock(rq);
activate_task(rq, p, 0);
- spin_unlock_irqrestore(&rq->lock, flags);
+ raw_spin_unlock_irqrestore(&rq->lock, flags);
}
/*
@@ -7401,9 +7448,9 @@ static void migrate_dead(unsigned int dead_cpu, struct task_struct *p)
* that's OK. No task can be added to this CPU, so iteration is
* fine.
*/
- spin_unlock_irq(&rq->lock);
+ raw_spin_unlock_irq(&rq->lock);
move_task_off_dead_cpu(dead_cpu, p);
- spin_lock_irq(&rq->lock);
+ raw_spin_lock_irq(&rq->lock);
put_task_struct(p);
}
@@ -7563,7 +7610,7 @@ static ctl_table *sd_alloc_ctl_cpu_table(int cpu)
static struct ctl_table_header *sd_sysctl_header;
static void register_sched_domain_sysctl(void)
{
- int i, cpu_num = num_online_cpus();
+ int i, cpu_num = num_possible_cpus();
struct ctl_table *entry = sd_alloc_ctl_entry(cpu_num + 1);
char buf[32];
@@ -7573,7 +7620,7 @@ static void register_sched_domain_sysctl(void)
if (entry == NULL)
return;
- for_each_online_cpu(i) {
+ for_each_possible_cpu(i) {
snprintf(buf, 32, "cpu%d", i);
entry->procname = kstrdup(buf, GFP_KERNEL);
entry->mode = 0555;
@@ -7669,13 +7716,13 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
/* Update our root-domain */
rq = cpu_rq(cpu);
- spin_lock_irqsave(&rq->lock, flags);
+ raw_spin_lock_irqsave(&rq->lock, flags);
if (rq->rd) {
BUG_ON(!cpumask_test_cpu(cpu, rq->rd->span));
set_rq_online(rq);
}
- spin_unlock_irqrestore(&rq->lock, flags);
+ raw_spin_unlock_irqrestore(&rq->lock, flags);
break;
#ifdef CONFIG_HOTPLUG_CPU
@@ -7700,14 +7747,13 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
put_task_struct(rq->migration_thread);
rq->migration_thread = NULL;
/* Idle task back to normal (off runqueue, low prio) */
- spin_lock_irq(&rq->lock);
+ raw_spin_lock_irq(&rq->lock);
update_rq_clock(rq);
deactivate_task(rq, rq->idle, 0);
- rq->idle->static_prio = MAX_PRIO;
__setscheduler(rq, rq->idle, SCHED_NORMAL, 0);
rq->idle->sched_class = &idle_sched_class;
migrate_dead_tasks(cpu);
- spin_unlock_irq(&rq->lock);
+ raw_spin_unlock_irq(&rq->lock);
cpuset_unlock();
migrate_nr_uninterruptible(rq);
BUG_ON(rq->nr_running != 0);
@@ -7717,30 +7763,30 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
* they didn't take sched_hotcpu_mutex. Just wake up
* the requestors.
*/
- spin_lock_irq(&rq->lock);
+ raw_spin_lock_irq(&rq->lock);
while (!list_empty(&rq->migration_queue)) {
struct migration_req *req;
req = list_entry(rq->migration_queue.next,
struct migration_req, list);
list_del_init(&req->list);
- spin_unlock_irq(&rq->lock);
+ raw_spin_unlock_irq(&rq->lock);
complete(&req->done);
- spin_lock_irq(&rq->lock);
+ raw_spin_lock_irq(&rq->lock);
}
- spin_unlock_irq(&rq->lock);
+ raw_spin_unlock_irq(&rq->lock);
break;
case CPU_DYING:
case CPU_DYING_FROZEN:
/* Update our root-domain */
rq = cpu_rq(cpu);
- spin_lock_irqsave(&rq->lock, flags);
+ raw_spin_lock_irqsave(&rq->lock, flags);
if (rq->rd) {
BUG_ON(!cpumask_test_cpu(cpu, rq->rd->span));
set_rq_offline(rq);
}
- spin_unlock_irqrestore(&rq->lock, flags);
+ raw_spin_unlock_irqrestore(&rq->lock, flags);
break;
#endif
}
@@ -7970,7 +8016,7 @@ static void rq_attach_root(struct rq *rq, struct root_domain *rd)
struct root_domain *old_rd = NULL;
unsigned long flags;
- spin_lock_irqsave(&rq->lock, flags);
+ raw_spin_lock_irqsave(&rq->lock, flags);
if (rq->rd) {
old_rd = rq->rd;
@@ -7996,7 +8042,7 @@ static void rq_attach_root(struct rq *rq, struct root_domain *rd)
if (cpumask_test_cpu(rq->cpu, cpu_active_mask))
set_rq_online(rq);
- spin_unlock_irqrestore(&rq->lock, flags);
+ raw_spin_unlock_irqrestore(&rq->lock, flags);
if (old_rd)
free_rootdomain(old_rd);
@@ -8282,14 +8328,14 @@ enum s_alloc {
*/
#ifdef CONFIG_SCHED_SMT
static DEFINE_PER_CPU(struct static_sched_domain, cpu_domains);
-static DEFINE_PER_CPU(struct static_sched_group, sched_group_cpus);
+static DEFINE_PER_CPU(struct static_sched_group, sched_groups);
static int
cpu_to_cpu_group(int cpu, const struct cpumask *cpu_map,
struct sched_group **sg, struct cpumask *unused)
{
if (sg)
- *sg = &per_cpu(sched_group_cpus, cpu).sg;
+ *sg = &per_cpu(sched_groups, cpu).sg;
return cpu;
}
#endif /* CONFIG_SCHED_SMT */
@@ -9099,7 +9145,7 @@ match1:
if (doms_new == NULL) {
ndoms_cur = 0;
doms_new = &fallback_doms;
- cpumask_andnot(doms_new[0], cpu_online_mask, cpu_isolated_map);
+ cpumask_andnot(doms_new[0], cpu_active_mask, cpu_isolated_map);
WARN_ON_ONCE(dattr_new);
}
@@ -9230,8 +9276,10 @@ static int update_sched_domains(struct notifier_block *nfb,
switch (action) {
case CPU_ONLINE:
case CPU_ONLINE_FROZEN:
- case CPU_DEAD:
- case CPU_DEAD_FROZEN:
+ case CPU_DOWN_PREPARE:
+ case CPU_DOWN_PREPARE_FROZEN:
+ case CPU_DOWN_FAILED:
+ case CPU_DOWN_FAILED_FROZEN:
partition_sched_domains(1, NULL, NULL);
return NOTIFY_OK;
@@ -9278,7 +9326,7 @@ void __init sched_init_smp(void)
#endif
get_online_cpus();
mutex_lock(&sched_domains_mutex);
- arch_init_sched_domains(cpu_online_mask);
+ arch_init_sched_domains(cpu_active_mask);
cpumask_andnot(non_isolated_cpus, cpu_possible_mask, cpu_isolated_map);
if (cpumask_empty(non_isolated_cpus))
cpumask_set_cpu(smp_processor_id(), non_isolated_cpus);
@@ -9351,13 +9399,13 @@ static void init_rt_rq(struct rt_rq *rt_rq, struct rq *rq)
#ifdef CONFIG_SMP
rt_rq->rt_nr_migratory = 0;
rt_rq->overloaded = 0;
- plist_head_init(&rt_rq->pushable_tasks, &rq->lock);
+ plist_head_init_raw(&rt_rq->pushable_tasks, &rq->lock);
#endif
rt_rq->rt_time = 0;
rt_rq->rt_throttled = 0;
rt_rq->rt_runtime = 0;
- spin_lock_init(&rt_rq->rt_runtime_lock);
+ raw_spin_lock_init(&rt_rq->rt_runtime_lock);
#ifdef CONFIG_RT_GROUP_SCHED
rt_rq->rt_nr_boosted = 0;
@@ -9517,7 +9565,7 @@ void __init sched_init(void)
struct rq *rq;
rq = cpu_rq(i);
- spin_lock_init(&rq->lock);
+ raw_spin_lock_init(&rq->lock);
rq->nr_running = 0;
rq->calc_load_active = 0;
rq->calc_load_update = jiffies + LOAD_FREQ;
@@ -9577,7 +9625,7 @@ void __init sched_init(void)
#elif defined CONFIG_USER_SCHED
init_tg_rt_entry(&root_task_group, &rq->rt, NULL, i, 0, NULL);
init_tg_rt_entry(&init_task_group,
- &per_cpu(init_rt_rq, i),
+ &per_cpu(init_rt_rq_var, i),
&per_cpu(init_sched_rt_entity, i), i, 1,
root_task_group.rt_se[i]);
#endif
@@ -9615,7 +9663,7 @@ void __init sched_init(void)
#endif
#ifdef CONFIG_RT_MUTEXES
- plist_head_init(&init_task.pi_waiters, &init_task.pi_lock);
+ plist_head_init_raw(&init_task.pi_waiters, &init_task.pi_lock);
#endif
/*
@@ -9659,7 +9707,7 @@ void __init sched_init(void)
#ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
static inline int preempt_count_equals(int preempt_offset)
{
- int nested = preempt_count() & ~PREEMPT_ACTIVE;
+ int nested = (preempt_count() & ~PREEMPT_ACTIVE) + rcu_preempt_depth();
return (nested == PREEMPT_INATOMIC_BASE + preempt_offset);
}
@@ -9740,13 +9788,13 @@ void normalize_rt_tasks(void)
continue;
}
- spin_lock(&p->pi_lock);
+ raw_spin_lock(&p->pi_lock);
rq = __task_rq_lock(p);
normalize_task(rq, p);
__task_rq_unlock(rq);
- spin_unlock(&p->pi_lock);
+ raw_spin_unlock(&p->pi_lock);
} while_each_thread(g, p);
read_unlock_irqrestore(&tasklist_lock, flags);
@@ -9842,13 +9890,15 @@ int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent)
se = kzalloc_node(sizeof(struct sched_entity),
GFP_KERNEL, cpu_to_node(i));
if (!se)
- goto err;
+ goto err_free_rq;
init_tg_cfs_entry(tg, cfs_rq, se, i, 0, parent->se[i]);
}
return 1;
+ err_free_rq:
+ kfree(cfs_rq);
err:
return 0;
}
@@ -9930,13 +9980,15 @@ int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent)
rt_se = kzalloc_node(sizeof(struct sched_rt_entity),
GFP_KERNEL, cpu_to_node(i));
if (!rt_se)
- goto err;
+ goto err_free_rq;
init_tg_rt_entry(tg, rt_rq, rt_se, i, 0, parent->rt_se[i]);
}
return 1;
+ err_free_rq:
+ kfree(rt_rq);
err:
return 0;
}
@@ -10070,7 +10122,7 @@ void sched_move_task(struct task_struct *tsk)
#ifdef CONFIG_FAIR_GROUP_SCHED
if (tsk->sched_class->moved_group)
- tsk->sched_class->moved_group(tsk);
+ tsk->sched_class->moved_group(tsk, on_rq);
#endif
if (unlikely(running))
@@ -10105,9 +10157,9 @@ static void set_se_shares(struct sched_entity *se, unsigned long shares)
struct rq *rq = cfs_rq->rq;
unsigned long flags;
- spin_lock_irqsave(&rq->lock, flags);
+ raw_spin_lock_irqsave(&rq->lock, flags);
__set_se_shares(se, shares);
- spin_unlock_irqrestore(&rq->lock, flags);
+ raw_spin_unlock_irqrestore(&rq->lock, flags);
}
static DEFINE_MUTEX(shares_mutex);
@@ -10292,18 +10344,18 @@ static int tg_set_bandwidth(struct task_group *tg,
if (err)
goto unlock;
- spin_lock_irq(&tg->rt_bandwidth.rt_runtime_lock);
+ raw_spin_lock_irq(&tg->rt_bandwidth.rt_runtime_lock);
tg->rt_bandwidth.rt_period = ns_to_ktime(rt_period);
tg->rt_bandwidth.rt_runtime = rt_runtime;
for_each_possible_cpu(i) {
struct rt_rq *rt_rq = tg->rt_rq[i];
- spin_lock(&rt_rq->rt_runtime_lock);
+ raw_spin_lock(&rt_rq->rt_runtime_lock);
rt_rq->rt_runtime = rt_runtime;
- spin_unlock(&rt_rq->rt_runtime_lock);
+ raw_spin_unlock(&rt_rq->rt_runtime_lock);
}
- spin_unlock_irq(&tg->rt_bandwidth.rt_runtime_lock);
+ raw_spin_unlock_irq(&tg->rt_bandwidth.rt_runtime_lock);
unlock:
read_unlock(&tasklist_lock);
mutex_unlock(&rt_constraints_mutex);
@@ -10408,15 +10460,15 @@ static int sched_rt_global_constraints(void)
if (sysctl_sched_rt_runtime == 0)
return -EBUSY;
- spin_lock_irqsave(&def_rt_bandwidth.rt_runtime_lock, flags);
+ raw_spin_lock_irqsave(&def_rt_bandwidth.rt_runtime_lock, flags);
for_each_possible_cpu(i) {
struct rt_rq *rt_rq = &cpu_rq(i)->rt;
- spin_lock(&rt_rq->rt_runtime_lock);
+ raw_spin_lock(&rt_rq->rt_runtime_lock);
rt_rq->rt_runtime = global_rt_runtime();
- spin_unlock(&rt_rq->rt_runtime_lock);
+ raw_spin_unlock(&rt_rq->rt_runtime_lock);
}
- spin_unlock_irqrestore(&def_rt_bandwidth.rt_runtime_lock, flags);
+ raw_spin_unlock_irqrestore(&def_rt_bandwidth.rt_runtime_lock, flags);
return 0;
}
@@ -10707,9 +10759,9 @@ static u64 cpuacct_cpuusage_read(struct cpuacct *ca, int cpu)
/*
* Take rq->lock to make 64-bit read safe on 32-bit platforms.
*/
- spin_lock_irq(&cpu_rq(cpu)->lock);
+ raw_spin_lock_irq(&cpu_rq(cpu)->lock);
data = *cpuusage;
- spin_unlock_irq(&cpu_rq(cpu)->lock);
+ raw_spin_unlock_irq(&cpu_rq(cpu)->lock);
#else
data = *cpuusage;
#endif
@@ -10725,9 +10777,9 @@ static void cpuacct_cpuusage_write(struct cpuacct *ca, int cpu, u64 val)
/*
* Take rq->lock to make 64-bit write safe on 32-bit platforms.
*/
- spin_lock_irq(&cpu_rq(cpu)->lock);
+ raw_spin_lock_irq(&cpu_rq(cpu)->lock);
*cpuusage = val;
- spin_unlock_irq(&cpu_rq(cpu)->lock);
+ raw_spin_unlock_irq(&cpu_rq(cpu)->lock);
#else
*cpuusage = val;
#endif
@@ -10961,9 +11013,9 @@ void synchronize_sched_expedited(void)
init_completion(&req->done);
req->task = NULL;
req->dest_cpu = RCU_MIGRATION_NEED_QS;
- spin_lock_irqsave(&rq->lock, flags);
+ raw_spin_lock_irqsave(&rq->lock, flags);
list_add(&req->list, &rq->migration_queue);
- spin_unlock_irqrestore(&rq->lock, flags);
+ raw_spin_unlock_irqrestore(&rq->lock, flags);
wake_up_process(rq->migration_thread);
}
for_each_online_cpu(cpu) {
@@ -10971,11 +11023,11 @@ void synchronize_sched_expedited(void)
req = &per_cpu(rcu_migration_req, cpu);
rq = cpu_rq(cpu);
wait_for_completion(&req->done);
- spin_lock_irqsave(&rq->lock, flags);
+ raw_spin_lock_irqsave(&rq->lock, flags);
if (unlikely(req->dest_cpu == RCU_MIGRATION_MUST_SYNC))
need_full_sync = 1;
req->dest_cpu = RCU_MIGRATION_IDLE;
- spin_unlock_irqrestore(&rq->lock, flags);
+ raw_spin_unlock_irqrestore(&rq->lock, flags);
}
rcu_expedited_state = RCU_EXPEDITED_STATE_IDLE;
synchronize_sched_expedited_count++;
generated by cgit v1.2.3-55-g7522 (git 2.39.0) at 2024-07-13 13:40:00 +0200