#define this_rq() (&__get_cpu_var(runqueues))
#define task_rq(p) cpu_rq(task_cpu(p))
#define cpu_curr(cpu) (cpu_rq(cpu)->curr)
+#define raw_rq() (&__raw_get_cpu_var(runqueues))
inline void update_rq_clock(struct rq *rq)
{
update_group_shares_cpu(struct task_group *tg, int cpu,
unsigned long sd_shares, unsigned long sd_rq_weight)
{
- unsigned long shares;
unsigned long rq_weight;
+ unsigned long shares;
+ int boost = 0;
if (!tg->se[cpu])
return;
rq_weight = tg->cfs_rq[cpu]->rq_weight;
+ if (!rq_weight) {
+ boost = 1;
+ rq_weight = NICE_0_LOAD;
+ }
/*
* \Sum shares * rq_weight
unsigned long flags;
spin_lock_irqsave(&rq->lock, flags);
- tg->cfs_rq[cpu]->shares = shares;
-
+ tg->cfs_rq[cpu]->shares = boost ? 0 : shares;
__set_se_shares(tg->se[cpu], shares);
spin_unlock_irqrestore(&rq->lock, flags);
}
*/
static int tg_shares_up(struct task_group *tg, void *data)
{
- unsigned long weight, rq_weight = 0;
+ unsigned long weight, rq_weight = 0, eff_weight = 0;
unsigned long shares = 0;
struct sched_domain *sd = data;
int i;
* run here it will not get delayed by group starvation.
*/
weight = tg->cfs_rq[i]->load.weight;
+ tg->cfs_rq[i]->rq_weight = weight;
+ rq_weight += weight;
+
if (!weight)
weight = NICE_0_LOAD;
- tg->cfs_rq[i]->rq_weight = weight;
- rq_weight += weight;
+ eff_weight += weight;
shares += tg->cfs_rq[i]->shares;
}
if (!sd->parent || !(sd->parent->flags & SD_LOAD_BALANCE))
shares = tg->shares;
- for_each_cpu(i, sched_domain_span(sd))
- update_group_shares_cpu(tg, i, shares, rq_weight);
+ for_each_cpu(i, sched_domain_span(sd)) {
+ unsigned long sd_rq_weight = rq_weight;
+
+ if (!tg->cfs_rq[i]->rq_weight)
+ sd_rq_weight = eff_weight;
+
+ update_group_shares_cpu(tg, i, shares, sd_rq_weight);
+ }
return 0;
}
static void update_shares(struct sched_domain *sd)
{
- u64 now = cpu_clock(raw_smp_processor_id());
- s64 elapsed = now - sd->last_update;
+ s64 elapsed;
+ u64 now;
+
+ if (root_task_group_empty())
+ return;
+
+ now = cpu_clock(raw_smp_processor_id());
+ elapsed = now - sd->last_update;
if (elapsed >= (s64)(u64)sysctl_sched_shares_ratelimit) {
sd->last_update = now;
static void update_shares_locked(struct rq *rq, struct sched_domain *sd)
{
+ if (root_task_group_empty())
+ return;
+
spin_unlock(&rq->lock);
update_shares(sd);
spin_lock(&rq->lock);
static void update_h_load(long cpu)
{
+ if (root_task_group_empty())
+ return;
+
walk_tg_tree(tg_load_down, tg_nop, (void *)cpu);
}
set_task_cpu(p, cpu);
/*
- * Make sure we do not leak PI boosting priority to the child:
+ * Make sure we do not leak PI boosting priority to the child.
*/
p->prio = current->normal_prio;
+
+ /*
+ * Revert to default priority/policy on fork if requested.
+ */
+ if (unlikely(p->sched_reset_on_fork)) {
+ if (p->policy == SCHED_FIFO || p->policy == SCHED_RR)
+ p->policy = SCHED_NORMAL;
+
+ if (p->normal_prio < DEFAULT_PRIO)
+ p->prio = DEFAULT_PRIO;
+
+ if (PRIO_TO_NICE(p->static_prio) < 0) {
+ p->static_prio = NICE_TO_PRIO(0);
+ set_load_weight(p);
+ }
+
+ /*
+ * We don't need the reset flag anymore after the fork. It has
+ * fulfilled its duty:
+ */
+ p->sched_reset_on_fork = 0;
+ }
+
if (!rt_prio(p->prio))
p->sched_class = &fair_sched_class;
* with the lock held can cause deadlocks; see schedule() for
* details.)
*/
-static void finish_task_switch(struct rq *rq, struct task_struct *prev)
+static int finish_task_switch(struct rq *rq, struct task_struct *prev)
__releases(rq->lock)
{
struct mm_struct *mm = rq->prev_mm;
long prev_state;
-#ifdef CONFIG_SMP
int post_schedule = 0;
+#ifdef CONFIG_SMP
if (current->sched_class->needs_post_schedule)
post_schedule = current->sched_class->needs_post_schedule(rq);
#endif
finish_arch_switch(prev);
perf_counter_task_sched_in(current, cpu_of(rq));
finish_lock_switch(rq, prev);
-#ifdef CONFIG_SMP
- if (post_schedule)
- current->sched_class->post_schedule(rq);
-#endif
fire_sched_in_preempt_notifiers(current);
if (mm)
kprobe_flush_task(prev);
put_task_struct(prev);
}
+
+ return post_schedule;
}
/**
__releases(rq->lock)
{
struct rq *rq = this_rq();
+ int post_schedule;
+
+ post_schedule = finish_task_switch(rq, prev);
+
+#ifdef CONFIG_SMP
+ if (post_schedule)
+ current->sched_class->post_schedule(rq);
+#endif
- finish_task_switch(rq, prev);
#ifdef __ARCH_WANT_UNLOCKED_CTXSW
/* In this case, finish_task_switch does not reenable preemption */
preempt_enable();
* context_switch - switch to the new MM and the new
* thread's register state.
*/
-static inline void
+static inline int
context_switch(struct rq *rq, struct task_struct *prev,
struct task_struct *next)
{
* CPUs since it called schedule(), thus the 'rq' on its stack
* frame will be invalid.
*/
- finish_task_switch(this_rq(), prev);
+ return finish_task_switch(this_rq(), prev);
}
/*
{
struct task_struct *prev, *next;
unsigned long *switch_count;
+ int post_schedule = 0;
struct rq *rq;
int cpu;
rq->curr = next;
++*switch_count;
- context_switch(rq, prev, next); /* unlocks the rq */
+ post_schedule = context_switch(rq, prev, next); /* unlocks the rq */
/*
* the context switch might have flipped the stack from under
* us, hence refresh the local variables.
*/
cpu = smp_processor_id();
rq = cpu_rq(cpu);
- } else
+ } else {
+#ifdef CONFIG_SMP
+ if (current->sched_class->needs_post_schedule)
+ post_schedule = current->sched_class->needs_post_schedule(rq);
+#endif
spin_unlock_irq(&rq->lock);
+ }
+
+#ifdef CONFIG_SMP
+ if (post_schedule)
+ current->sched_class->post_schedule(rq);
+#endif
if (unlikely(reacquire_kernel_lock(current) < 0))
goto need_resched_nonpreemptible;
unsigned long flags;
const struct sched_class *prev_class = p->sched_class;
struct rq *rq;
+ int reset_on_fork;
/* may grab non-irq protected spin_locks */
BUG_ON(in_interrupt());
recheck:
/* double check policy once rq lock held */
- if (policy < 0)
+ if (policy < 0) {
+ reset_on_fork = p->sched_reset_on_fork;
policy = oldpolicy = p->policy;
- else if (policy != SCHED_FIFO && policy != SCHED_RR &&
- policy != SCHED_NORMAL && policy != SCHED_BATCH &&
- policy != SCHED_IDLE)
- return -EINVAL;
+ } else {
+ reset_on_fork = !!(policy & SCHED_RESET_ON_FORK);
+ policy &= ~SCHED_RESET_ON_FORK;
+
+ if (policy != SCHED_FIFO && policy != SCHED_RR &&
+ policy != SCHED_NORMAL && policy != SCHED_BATCH &&
+ policy != SCHED_IDLE)
+ return -EINVAL;
+ }
+
/*
* Valid priorities for SCHED_FIFO and SCHED_RR are
* 1..MAX_USER_RT_PRIO-1, valid priority for SCHED_NORMAL,
/* can't change other user's priorities */
if (!check_same_owner(p))
return -EPERM;
+
+ /* Normal users shall not reset the sched_reset_on_fork flag */
+ if (p->sched_reset_on_fork && !reset_on_fork)
+ return -EPERM;
}
if (user) {
if (running)
p->sched_class->put_prev_task(rq, p);
+ p->sched_reset_on_fork = reset_on_fork;
+
oldprio = p->prio;
__setscheduler(rq, p, policy, param->sched_priority);
if (p) {
retval = security_task_getscheduler(p);
if (!retval)
- retval = p->policy;
+ retval = p->policy
+ | (p->sched_reset_on_fork ? SCHED_RESET_ON_FORK : 0);
}
read_unlock(&tasklist_lock);
return retval;
}
/**
- * sys_sched_getscheduler - get the RT priority of a thread
+ * sys_sched_getparam - get the RT priority of a thread
* @pid: the pid in question.
* @param: structure containing the RT priority.
*/
static void __cond_resched(void)
{
-#ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
- __might_sleep(__FILE__, __LINE__);
-#endif
- /*
- * The BKS might be reacquired before we have dropped
- * PREEMPT_ACTIVE, which could trigger a second
- * cond_resched() call.
- */
- do {
- add_preempt_count(PREEMPT_ACTIVE);
- schedule();
- sub_preempt_count(PREEMPT_ACTIVE);
- } while (need_resched());
+ add_preempt_count(PREEMPT_ACTIVE);
+ schedule();
+ sub_preempt_count(PREEMPT_ACTIVE);
}
int __sched _cond_resched(void)
EXPORT_SYMBOL(_cond_resched);
/*
- * cond_resched_lock() - if a reschedule is pending, drop the given lock,
+ * __cond_resched_lock() - if a reschedule is pending, drop the given lock,
* call schedule, and on return reacquire the lock.
*
* This works OK both with and without CONFIG_PREEMPT. We do strange low-level
* operations here to prevent schedule() from being called twice (once via
* spin_unlock(), once by hand).
*/
-int cond_resched_lock(spinlock_t *lock)
+int __cond_resched_lock(spinlock_t *lock)
{
int resched = should_resched();
int ret = 0;
}
return ret;
}
-EXPORT_SYMBOL(cond_resched_lock);
+EXPORT_SYMBOL(__cond_resched_lock);
-int __sched cond_resched_softirq(void)
+int __sched __cond_resched_softirq(void)
{
BUG_ON(!in_softirq());
}
return 0;
}
-EXPORT_SYMBOL(cond_resched_softirq);
+EXPORT_SYMBOL(__cond_resched_softirq);
/**
* yield - yield the current processor to other threads.
*/
void __sched io_schedule(void)
{
- struct rq *rq = &__raw_get_cpu_var(runqueues);
+ struct rq *rq = raw_rq();
delayacct_blkio_start();
atomic_inc(&rq->nr_iowait);
long __sched io_schedule_timeout(long timeout)
{
- struct rq *rq = &__raw_get_cpu_var(runqueues);
+ struct rq *rq = raw_rq();
long ret;
delayacct_blkio_start();
static void calc_global_load_remove(struct rq *rq)
{
atomic_long_sub(rq->calc_load_active, &calc_load_tasks);
+ rq->calc_load_active = 0;
}
#endif /* CONFIG_HOTPLUG_CPU */
task_rq_unlock(rq, &flags);
get_task_struct(p);
cpu_rq(cpu)->migration_thread = p;
+ rq->calc_load_update = calc_load_update;
break;
case CPU_ONLINE:
/* Update our root-domain */
rq = cpu_rq(cpu);
spin_lock_irqsave(&rq->lock, flags);
- rq->calc_load_update = calc_load_update;
- rq->calc_load_active = 0;
if (rq->rd) {
BUG_ON(!cpumask_test_cpu(cpu, rq->rd->span));
migration_call(&migration_notifier, CPU_ONLINE, cpu);
register_cpu_notifier(&migration_notifier);
- return err;
+ return 0;
}
early_initcall(migration_init);
#endif
}
#ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
-void __might_sleep(char *file, int line)
+static inline int preempt_count_equals(int preempt_offset)
+{
+ int nested = preempt_count() & ~PREEMPT_ACTIVE;
+
+ return (nested == PREEMPT_INATOMIC_BASE + preempt_offset);
+}
+
+void __might_sleep(char *file, int line, int preempt_offset)
{
#ifdef in_atomic
static unsigned long prev_jiffy; /* ratelimiting */
- if ((!in_atomic() && !irqs_disabled()) ||
- system_state != SYSTEM_RUNNING || oops_in_progress)
+ if ((preempt_count_equals(preempt_offset) && !irqs_disabled()) ||
+ system_state != SYSTEM_RUNNING || oops_in_progress)
return;
if (time_before(jiffies, prev_jiffy + HZ) && prev_jiffy)
return;
projects / deliverable / linux.git / blobdiff