summaryrefslogtreecommitdiffstats
path: root/kernel/sched
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/sched')
-rw-r--r--kernel/sched/core.c103
-rw-r--r--kernel/sched/cpudeadline.c37
-rw-r--r--kernel/sched/cpudeadline.h6
-rw-r--r--kernel/sched/cpupri.c16
-rw-r--r--kernel/sched/cpupri.h2
-rw-r--r--kernel/sched/cputime.c32
-rw-r--r--kernel/sched/deadline.c5
-rw-r--r--kernel/sched/fair.c16
-rw-r--r--kernel/sched/wait.c2
9 files changed, 147 insertions, 72 deletions
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 268a45ea238c..a62a7dec3986 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -90,6 +90,22 @@
#define CREATE_TRACE_POINTS
#include <trace/events/sched.h>
+#ifdef smp_mb__before_atomic
+void __smp_mb__before_atomic(void)
+{
+ smp_mb__before_atomic();
+}
+EXPORT_SYMBOL(__smp_mb__before_atomic);
+#endif
+
+#ifdef smp_mb__after_atomic
+void __smp_mb__after_atomic(void)
+{
+ smp_mb__after_atomic();
+}
+EXPORT_SYMBOL(__smp_mb__after_atomic);
+#endif
+
void start_bandwidth_timer(struct hrtimer *period_timer, ktime_t period)
{
unsigned long delta;
@@ -2192,7 +2208,7 @@ static inline void post_schedule(struct rq *rq)
* schedule_tail - first thing a freshly forked thread must call.
* @prev: the thread we just switched away from.
*/
-asmlinkage void schedule_tail(struct task_struct *prev)
+asmlinkage __visible void schedule_tail(struct task_struct *prev)
__releases(rq->lock)
{
struct rq *rq = this_rq();
@@ -2592,8 +2608,14 @@ pick_next_task(struct rq *rq, struct task_struct *prev)
if (likely(prev->sched_class == class &&
rq->nr_running == rq->cfs.h_nr_running)) {
p = fair_sched_class.pick_next_task(rq, prev);
- if (likely(p && p != RETRY_TASK))
- return p;
+ if (unlikely(p == RETRY_TASK))
+ goto again;
+
+ /* assumes fair_sched_class->next == idle_sched_class */
+ if (unlikely(!p))
+ p = idle_sched_class.pick_next_task(rq, prev);
+
+ return p;
}
again:
@@ -2741,7 +2763,7 @@ static inline void sched_submit_work(struct task_struct *tsk)
blk_schedule_flush_plug(tsk);
}
-asmlinkage void __sched schedule(void)
+asmlinkage __visible void __sched schedule(void)
{
struct task_struct *tsk = current;
@@ -2751,7 +2773,7 @@ asmlinkage void __sched schedule(void)
EXPORT_SYMBOL(schedule);
#ifdef CONFIG_CONTEXT_TRACKING
-asmlinkage void __sched schedule_user(void)
+asmlinkage __visible void __sched schedule_user(void)
{
/*
* If we come here after a random call to set_need_resched(),
@@ -2783,7 +2805,7 @@ void __sched schedule_preempt_disabled(void)
* off of preempt_enable. Kernel preemptions off return from interrupt
* occur there and call schedule directly.
*/
-asmlinkage void __sched notrace preempt_schedule(void)
+asmlinkage __visible void __sched notrace preempt_schedule(void)
{
/*
* If there is a non-zero preempt_count or interrupts are disabled,
@@ -2813,7 +2835,7 @@ EXPORT_SYMBOL(preempt_schedule);
* Note, that this is called and return with irqs disabled. This will
* protect us against recursive calling from irq.
*/
-asmlinkage void __sched preempt_schedule_irq(void)
+asmlinkage __visible void __sched preempt_schedule_irq(void)
{
enum ctx_state prev_state;
@@ -3124,6 +3146,7 @@ __setparam_dl(struct task_struct *p, const struct sched_attr *attr)
dl_se->dl_bw = to_ratio(dl_se->dl_period, dl_se->dl_runtime);
dl_se->dl_throttled = 0;
dl_se->dl_new = 1;
+ dl_se->dl_yielded = 0;
}
static void __setscheduler_params(struct task_struct *p,
@@ -3188,17 +3211,40 @@ __getparam_dl(struct task_struct *p, struct sched_attr *attr)
* We ask for the deadline not being zero, and greater or equal
* than the runtime, as well as the period of being zero or
* greater than deadline. Furthermore, we have to be sure that
- * user parameters are above the internal resolution (1us); we
- * check sched_runtime only since it is always the smaller one.
+ * user parameters are above the internal resolution of 1us (we
+ * check sched_runtime only since it is always the smaller one) and
+ * below 2^63 ns (we have to check both sched_deadline and
+ * sched_period, as the latter can be zero).
*/
static bool
__checkparam_dl(const struct sched_attr *attr)
{
- return attr && attr->sched_deadline != 0 &&
- (attr->sched_period == 0 ||
- (s64)(attr->sched_period - attr->sched_deadline) >= 0) &&
- (s64)(attr->sched_deadline - attr->sched_runtime ) >= 0 &&
- attr->sched_runtime >= (2 << (DL_SCALE - 1));
+ /* deadline != 0 */
+ if (attr->sched_deadline == 0)
+ return false;
+
+ /*
+ * Since we truncate DL_SCALE bits, make sure we're at least
+ * that big.
+ */
+ if (attr->sched_runtime < (1ULL << DL_SCALE))
+ return false;
+
+ /*
+ * Since we use the MSB for wrap-around and sign issues, make
+ * sure it's not set (mind that period can be equal to zero).
+ */
+ if (attr->sched_deadline & (1ULL << 63) ||
+ attr->sched_period & (1ULL << 63))
+ return false;
+
+ /* runtime <= deadline <= period (if period != 0) */
+ if ((attr->sched_period != 0 &&
+ attr->sched_period < attr->sched_deadline) ||
+ attr->sched_deadline < attr->sched_runtime)
+ return false;
+
+ return true;
}
/*
@@ -3639,6 +3685,7 @@ SYSCALL_DEFINE2(sched_setparam, pid_t, pid, struct sched_param __user *, param)
* sys_sched_setattr - same as above, but with extended sched_attr
* @pid: the pid in question.
* @uattr: structure containing the extended parameters.
+ * @flags: for future extension.
*/
SYSCALL_DEFINE3(sched_setattr, pid_t, pid, struct sched_attr __user *, uattr,
unsigned int, flags)
@@ -3650,8 +3697,12 @@ SYSCALL_DEFINE3(sched_setattr, pid_t, pid, struct sched_attr __user *, uattr,
if (!uattr || pid < 0 || flags)
return -EINVAL;
- if (sched_copy_attr(uattr, &attr))
- return -EFAULT;
+ retval = sched_copy_attr(uattr, &attr);
+ if (retval)
+ return retval;
+
+ if (attr.sched_policy < 0)
+ return -EINVAL;
rcu_read_lock();
retval = -ESRCH;
@@ -3701,7 +3752,7 @@ SYSCALL_DEFINE1(sched_getscheduler, pid_t, pid)
*/
SYSCALL_DEFINE2(sched_getparam, pid_t, pid, struct sched_param __user *, param)
{
- struct sched_param lp;
+ struct sched_param lp = { .sched_priority = 0 };
struct task_struct *p;
int retval;
@@ -3718,11 +3769,8 @@ SYSCALL_DEFINE2(sched_getparam, pid_t, pid, struct sched_param __user *, param)
if (retval)
goto out_unlock;
- if (task_has_dl_policy(p)) {
- retval = -EINVAL;
- goto out_unlock;
- }
- lp.sched_priority = p->rt_priority;
+ if (task_has_rt_policy(p))
+ lp.sched_priority = p->rt_priority;
rcu_read_unlock();
/*
@@ -3783,6 +3831,7 @@ err_size:
* @pid: the pid in question.
* @uattr: structure containing the extended parameters.
* @size: sizeof(attr) for fwd/bwd comp.
+ * @flags: for future extension.
*/
SYSCALL_DEFINE4(sched_getattr, pid_t, pid, struct sched_attr __user *, uattr,
unsigned int, size, unsigned int, flags)
@@ -4051,6 +4100,7 @@ static void __cond_resched(void)
int __sched _cond_resched(void)
{
+ rcu_cond_resched();
if (should_resched()) {
__cond_resched();
return 1;
@@ -4069,15 +4119,18 @@ EXPORT_SYMBOL(_cond_resched);
*/
int __cond_resched_lock(spinlock_t *lock)
{
+ bool need_rcu_resched = rcu_should_resched();
int resched = should_resched();
int ret = 0;
lockdep_assert_held(lock);
- if (spin_needbreak(lock) || resched) {
+ if (spin_needbreak(lock) || resched || need_rcu_resched) {
spin_unlock(lock);
if (resched)
__cond_resched();
+ else if (unlikely(need_rcu_resched))
+ rcu_resched();
else
cpu_relax();
ret = 1;
@@ -4091,6 +4144,7 @@ int __sched __cond_resched_softirq(void)
{
BUG_ON(!in_softirq());
+ rcu_cond_resched(); /* BH disabled OK, just recording QSes. */
if (should_resched()) {
local_bh_enable();
__cond_resched();
@@ -5043,7 +5097,6 @@ static int sched_cpu_active(struct notifier_block *nfb,
unsigned long action, void *hcpu)
{
switch (action & ~CPU_TASKS_FROZEN) {
- case CPU_STARTING:
case CPU_DOWN_FAILED:
set_cpu_active((long)hcpu, true);
return NOTIFY_OK;
@@ -6017,6 +6070,8 @@ sd_numa_init(struct sched_domain_topology_level *tl, int cpu)
,
.last_balance = jiffies,
.balance_interval = sd_weight,
+ .max_newidle_lb_cost = 0,
+ .next_decay_max_lb_cost = jiffies,
};
SD_INIT_NAME(sd, NUMA);
sd->private = &tl->data;
diff --git a/kernel/sched/cpudeadline.c b/kernel/sched/cpudeadline.c
index 5b9bb42b2d47..bd95963dae80 100644
--- a/kernel/sched/cpudeadline.c
+++ b/kernel/sched/cpudeadline.c
@@ -13,6 +13,7 @@
#include <linux/gfp.h>
#include <linux/kernel.h>
+#include <linux/slab.h>
#include "cpudeadline.h"
static inline int parent(int i)
@@ -39,8 +40,10 @@ static void cpudl_exchange(struct cpudl *cp, int a, int b)
{
int cpu_a = cp->elements[a].cpu, cpu_b = cp->elements[b].cpu;
- swap(cp->elements[a], cp->elements[b]);
- swap(cp->cpu_to_idx[cpu_a], cp->cpu_to_idx[cpu_b]);
+ swap(cp->elements[a].cpu, cp->elements[b].cpu);
+ swap(cp->elements[a].dl , cp->elements[b].dl );
+
+ swap(cp->elements[cpu_a].idx, cp->elements[cpu_b].idx);
}
static void cpudl_heapify(struct cpudl *cp, int idx)
@@ -140,7 +143,7 @@ void cpudl_set(struct cpudl *cp, int cpu, u64 dl, int is_valid)
WARN_ON(!cpu_present(cpu));
raw_spin_lock_irqsave(&cp->lock, flags);
- old_idx = cp->cpu_to_idx[cpu];
+ old_idx = cp->elements[cpu].idx;
if (!is_valid) {
/* remove item */
if (old_idx == IDX_INVALID) {
@@ -155,8 +158,8 @@ void cpudl_set(struct cpudl *cp, int cpu, u64 dl, int is_valid)
cp->elements[old_idx].dl = cp->elements[cp->size - 1].dl;
cp->elements[old_idx].cpu = new_cpu;
cp->size--;
- cp->cpu_to_idx[new_cpu] = old_idx;
- cp->cpu_to_idx[cpu] = IDX_INVALID;
+ cp->elements[new_cpu].idx = old_idx;
+ cp->elements[cpu].idx = IDX_INVALID;
while (old_idx > 0 && dl_time_before(
cp->elements[parent(old_idx)].dl,
cp->elements[old_idx].dl)) {
@@ -173,7 +176,7 @@ void cpudl_set(struct cpudl *cp, int cpu, u64 dl, int is_valid)
cp->size++;
cp->elements[cp->size - 1].dl = 0;
cp->elements[cp->size - 1].cpu = cpu;
- cp->cpu_to_idx[cpu] = cp->size - 1;
+ cp->elements[cpu].idx = cp->size - 1;
cpudl_change_key(cp, cp->size - 1, dl);
cpumask_clear_cpu(cpu, cp->free_cpus);
} else {
@@ -195,10 +198,21 @@ int cpudl_init(struct cpudl *cp)
memset(cp, 0, sizeof(*cp));
raw_spin_lock_init(&cp->lock);
cp->size = 0;
- for (i = 0; i < NR_CPUS; i++)
- cp->cpu_to_idx[i] = IDX_INVALID;
- if (!alloc_cpumask_var(&cp->free_cpus, GFP_KERNEL))
+
+ cp->elements = kcalloc(nr_cpu_ids,
+ sizeof(struct cpudl_item),
+ GFP_KERNEL);
+ if (!cp->elements)
+ return -ENOMEM;
+
+ if (!alloc_cpumask_var(&cp->free_cpus, GFP_KERNEL)) {
+ kfree(cp->elements);
return -ENOMEM;
+ }
+
+ for_each_possible_cpu(i)
+ cp->elements[i].idx = IDX_INVALID;
+
cpumask_setall(cp->free_cpus);
return 0;
@@ -210,7 +224,6 @@ int cpudl_init(struct cpudl *cp)
*/
void cpudl_cleanup(struct cpudl *cp)
{
- /*
- * nothing to do for the moment
- */
+ free_cpumask_var(cp->free_cpus);
+ kfree(cp->elements);
}
diff --git a/kernel/sched/cpudeadline.h b/kernel/sched/cpudeadline.h
index a202789a412c..538c9796ad4a 100644
--- a/kernel/sched/cpudeadline.h
+++ b/kernel/sched/cpudeadline.h
@@ -5,17 +5,17 @@
#define IDX_INVALID -1
-struct array_item {
+struct cpudl_item {
u64 dl;
int cpu;
+ int idx;
};
struct cpudl {
raw_spinlock_t lock;
int size;
- int cpu_to_idx[NR_CPUS];
- struct array_item elements[NR_CPUS];
cpumask_var_t free_cpus;
+ struct cpudl_item *elements;
};
diff --git a/kernel/sched/cpupri.c b/kernel/sched/cpupri.c
index 8b836b376d91..981fcd7dc394 100644
--- a/kernel/sched/cpupri.c
+++ b/kernel/sched/cpupri.c
@@ -30,6 +30,7 @@
#include <linux/gfp.h>
#include <linux/sched.h>
#include <linux/sched/rt.h>
+#include <linux/slab.h>
#include "cpupri.h"
/* Convert between a 140 based task->prio, and our 102 based cpupri */
@@ -70,8 +71,7 @@ int cpupri_find(struct cpupri *cp, struct task_struct *p,
int idx = 0;
int task_pri = convert_prio(p->prio);
- if (task_pri >= MAX_RT_PRIO)
- return 0;
+ BUG_ON(task_pri >= CPUPRI_NR_PRIORITIES);
for (idx = 0; idx < task_pri; idx++) {
struct cpupri_vec *vec = &cp->pri_to_cpu[idx];
@@ -165,7 +165,7 @@ void cpupri_set(struct cpupri *cp, int cpu, int newpri)
* do a write memory barrier, and then update the count, to
* make sure the vector is visible when count is set.
*/
- smp_mb__before_atomic_inc();
+ smp_mb__before_atomic();
atomic_inc(&(vec)->count);
do_mb = 1;
}
@@ -185,14 +185,14 @@ void cpupri_set(struct cpupri *cp, int cpu, int newpri)
* the new priority vec.
*/
if (do_mb)
- smp_mb__after_atomic_inc();
+ smp_mb__after_atomic();
/*
* When removing from the vector, we decrement the counter first
* do a memory barrier and then clear the mask.
*/
atomic_dec(&(vec)->count);
- smp_mb__after_atomic_inc();
+ smp_mb__after_atomic();
cpumask_clear_cpu(cpu, vec->mask);
}
@@ -219,8 +219,13 @@ int cpupri_init(struct cpupri *cp)
goto cleanup;
}
+ cp->cpu_to_pri = kcalloc(nr_cpu_ids, sizeof(int), GFP_KERNEL);
+ if (!cp->cpu_to_pri)
+ goto cleanup;
+
for_each_possible_cpu(i)
cp->cpu_to_pri[i] = CPUPRI_INVALID;
+
return 0;
cleanup:
@@ -237,6 +242,7 @@ void cpupri_cleanup(struct cpupri *cp)
{
int i;
+ kfree(cp->cpu_to_pri);
for (i = 0; i < CPUPRI_NR_PRIORITIES; i++)
free_cpumask_var(cp->pri_to_cpu[i].mask);
}
diff --git a/kernel/sched/cpupri.h b/kernel/sched/cpupri.h
index f6d756173491..6b033347fdfd 100644
--- a/kernel/sched/cpupri.h
+++ b/kernel/sched/cpupri.h
@@ -17,7 +17,7 @@ struct cpupri_vec {
struct cpupri {
struct cpupri_vec pri_to_cpu[CPUPRI_NR_PRIORITIES];
- int cpu_to_pri[NR_CPUS];
+ int *cpu_to_pri;
};
#ifdef CONFIG_SMP
diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c
index a95097cb4591..72fdf06ef865 100644
--- a/kernel/sched/cputime.c
+++ b/kernel/sched/cputime.c
@@ -332,50 +332,50 @@ out:
* softirq as those do not count in task exec_runtime any more.
*/
static void irqtime_account_process_tick(struct task_struct *p, int user_tick,
- struct rq *rq)
+ struct rq *rq, int ticks)
{
- cputime_t one_jiffy_scaled = cputime_to_scaled(cputime_one_jiffy);
+ cputime_t scaled = cputime_to_scaled(cputime_one_jiffy);
+ u64 cputime = (__force u64) cputime_one_jiffy;
u64 *cpustat = kcpustat_this_cpu->cpustat;
if (steal_account_process_tick())
return;
+ cputime *= ticks;
+ scaled *= ticks;
+
if (irqtime_account_hi_update()) {
- cpustat[CPUTIME_IRQ] += (__force u64) cputime_one_jiffy;
+ cpustat[CPUTIME_IRQ] += cputime;
} else if (irqtime_account_si_update()) {
- cpustat[CPUTIME_SOFTIRQ] += (__force u64) cputime_one_jiffy;
+ cpustat[CPUTIME_SOFTIRQ] += cputime;
} else if (this_cpu_ksoftirqd() == p) {
/*
* ksoftirqd time do not get accounted in cpu_softirq_time.
* So, we have to handle it separately here.
* Also, p->stime needs to be updated for ksoftirqd.
*/
- __account_system_time(p, cputime_one_jiffy, one_jiffy_scaled,
- CPUTIME_SOFTIRQ);
+ __account_system_time(p, cputime, scaled, CPUTIME_SOFTIRQ);
} else if (user_tick) {
- account_user_time(p, cputime_one_jiffy, one_jiffy_scaled);
+ account_user_time(p, cputime, scaled);
} else if (p == rq->idle) {
- account_idle_time(cputime_one_jiffy);
+ account_idle_time(cputime);
} else if (p->flags & PF_VCPU) { /* System time or guest time */
- account_guest_time(p, cputime_one_jiffy, one_jiffy_scaled);
+ account_guest_time(p, cputime, scaled);
} else {
- __account_system_time(p, cputime_one_jiffy, one_jiffy_scaled,
- CPUTIME_SYSTEM);
+ __account_system_time(p, cputime, scaled, CPUTIME_SYSTEM);
}
}
static void irqtime_account_idle_ticks(int ticks)
{
- int i;
struct rq *rq = this_rq();
- for (i = 0; i < ticks; i++)
- irqtime_account_process_tick(current, 0, rq);
+ irqtime_account_process_tick(current, 0, rq, ticks);
}
#else /* CONFIG_IRQ_TIME_ACCOUNTING */
static inline void irqtime_account_idle_ticks(int ticks) {}
static inline void irqtime_account_process_tick(struct task_struct *p, int user_tick,
- struct rq *rq) {}
+ struct rq *rq, int nr_ticks) {}
#endif /* CONFIG_IRQ_TIME_ACCOUNTING */
/*
@@ -464,7 +464,7 @@ void account_process_tick(struct task_struct *p, int user_tick)
return;
if (sched_clock_irqtime) {
- irqtime_account_process_tick(p, user_tick, rq);
+ irqtime_account_process_tick(p, user_tick, rq, 1);
return;
}
diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index b08095786cb8..800e99b99075 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -528,6 +528,7 @@ static enum hrtimer_restart dl_task_timer(struct hrtimer *timer)
sched_clock_tick();
update_rq_clock(rq);
dl_se->dl_throttled = 0;
+ dl_se->dl_yielded = 0;
if (p->on_rq) {
enqueue_task_dl(rq, p, ENQUEUE_REPLENISH);
if (task_has_dl_policy(rq->curr))
@@ -893,10 +894,10 @@ static void yield_task_dl(struct rq *rq)
* We make the task go to sleep until its current deadline by
* forcing its runtime to zero. This way, update_curr_dl() stops
* it and the bandwidth timer will wake it up and will give it
- * new scheduling parameters (thanks to dl_new=1).
+ * new scheduling parameters (thanks to dl_yielded=1).
*/
if (p->dl.runtime > 0) {
- rq->curr->dl.dl_new = 1;
+ rq->curr->dl.dl_yielded = 1;
p->dl.runtime = 0;
}
update_curr_dl(rq);
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 7570dd969c28..0fdb96de81a5 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -6653,6 +6653,7 @@ static int idle_balance(struct rq *this_rq)
int this_cpu = this_rq->cpu;
idle_enter_fair(this_rq);
+
/*
* We must set idle_stamp _before_ calling idle_balance(), such that we
* measure the duration of idle_balance() as idle time.
@@ -6705,14 +6706,16 @@ static int idle_balance(struct rq *this_rq)
raw_spin_lock(&this_rq->lock);
+ if (curr_cost > this_rq->max_idle_balance_cost)
+ this_rq->max_idle_balance_cost = curr_cost;
+
/*
- * While browsing the domains, we released the rq lock.
- * A task could have be enqueued in the meantime
+ * While browsing the domains, we released the rq lock, a task could
+ * have been enqueued in the meantime. Since we're not going idle,
+ * pretend we pulled a task.
*/
- if (this_rq->cfs.h_nr_running && !pulled_task) {
+ if (this_rq->cfs.h_nr_running && !pulled_task)
pulled_task = 1;
- goto out;
- }
if (pulled_task || time_after(jiffies, this_rq->next_balance)) {
/*
@@ -6722,9 +6725,6 @@ static int idle_balance(struct rq *this_rq)
this_rq->next_balance = next_balance;
}
- if (curr_cost > this_rq->max_idle_balance_cost)
- this_rq->max_idle_balance_cost = curr_cost;
-
out:
/* Is there a task of a high priority class? */
if (this_rq->nr_running != this_rq->cfs.h_nr_running &&
diff --git a/kernel/sched/wait.c b/kernel/sched/wait.c
index 7d50f794e248..0ffa20ae657b 100644
--- a/kernel/sched/wait.c
+++ b/kernel/sched/wait.c
@@ -394,7 +394,7 @@ EXPORT_SYMBOL(__wake_up_bit);
*
* In order for this to function properly, as it uses waitqueue_active()
* internally, some kind of memory barrier must be done prior to calling
- * this. Typically, this will be smp_mb__after_clear_bit(), but in some
+ * this. Typically, this will be smp_mb__after_atomic(), but in some
* cases where bitflags are manipulated non-atomically under a lock, one
* may need to use a less regular barrier, such fs/inode.c's smp_mb(),
* because spin_unlock() does not guarantee a memory barrier.