static inline int rt_policy(int policy)
{
- if (unlikely(policy == SCHED_FIFO || policy == SCHED_RR))
+ if (policy == SCHED_FIFO || policy == SCHED_RR)
return 1;
return 0;
}
if (p->sched_class->task_woken)
p->sched_class->task_woken(rq, p);
- if (unlikely(rq->idle_stamp)) {
+ if (rq->idle_stamp) {
u64 delta = rq->clock - rq->idle_stamp;
u64 max = 2*sysctl_sched_migration_cost;
#if defined(CONFIG_SMP)
p->on_cpu = 0;
#endif
-#ifdef CONFIG_PREEMPT
+#ifdef CONFIG_PREEMPT_COUNT
/* Want to start with kernel preemption disabled. */
task_thread_info(p)->preempt_count = 1;
#endif
static inline bool owner_running(struct mutex *lock, struct task_struct *owner)
{
- bool ret = false;
-
- rcu_read_lock();
if (lock->owner != owner)
- goto fail;
+ return false;
/*
* Ensure we emit the owner->on_cpu, dereference _after_ checking
*/
barrier();
- ret = owner->on_cpu;
-fail:
- rcu_read_unlock();
-
- return ret;
+ return owner->on_cpu;
}
/*
if (!sched_feat(OWNER_SPIN))
return 0;
+ rcu_read_lock();
while (owner_running(lock, owner)) {
if (need_resched())
- return 0;
+ break;
arch_mutex_cpu_relax();
}
+ rcu_read_unlock();
/*
- * If the owner changed to another task there is likely
- * heavy contention, stop spinning.
+ * We break out the loop above on need_resched() and when the
+ * owner changed, which is a sign for heavy contention. Return
+ * success only when lock->owner is NULL.
*/
- if (lock->owner)
- return 0;
-
- return 1;
+ return lock->owner == NULL;
}
#endif
scheduler_running = 1;
}
-#ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
+#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
static inline int preempt_count_equals(int preempt_offset)
{
int nested = (preempt_count() & ~PREEMPT_ACTIVE) + rcu_preempt_depth();
void __might_sleep(const char *file, int line, int preempt_offset)
{
-#ifdef in_atomic
static unsigned long prev_jiffy; /* ratelimiting */
if ((preempt_count_equals(preempt_offset) && !irqs_disabled()) ||
if (irqs_disabled())
print_irqtrace_events(current);
dump_stack();
-#endif
}
EXPORT_SYMBOL(__might_sleep);
#endif