diff options
author | Ingo Molnar <mingo@elte.hu> | 2008-08-26 10:25:59 +0200 |
---|---|---|
committer | Ingo Molnar <mingo@elte.hu> | 2008-08-26 10:25:59 +0200 |
commit | 3cf430b0636045dc524759a0852293ba037732a7 (patch) | |
tree | 2c4e03f9028dc23ab4e6ca5a3a5a263af397984f /kernel/sched.c | |
parent | 93dcf55f828b035fc93fc19eb03c1390e1e6d570 (diff) | |
parent | 83097aca8567a0bd593534853b71fe0fa9a75d69 (diff) |
Merge branch 'linus' into sched/devel
Diffstat (limited to 'kernel/sched.c')
-rw-r--r-- | kernel/sched.c | 54 |
1 files changed, 51 insertions, 3 deletions
diff --git a/kernel/sched.c b/kernel/sched.c index 6a43c8942b0..29e2ec0bd83 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -808,9 +808,9 @@ const_debug unsigned int sysctl_sched_nr_migrate = 32; /* * ratelimit for updating the group shares. - * default: 0.5ms + * default: 0.25ms */ -const_debug unsigned int sysctl_sched_shares_ratelimit = 500000; +unsigned int sysctl_sched_shares_ratelimit = 250000; /* * period over which we measure -rt task cpu usage in us. @@ -4663,6 +4663,52 @@ int __sched wait_for_completion_killable(struct completion *x) } EXPORT_SYMBOL(wait_for_completion_killable); +/** + * try_wait_for_completion - try to decrement a completion without blocking + * @x: completion structure + * + * Returns: 0 if a decrement cannot be done without blocking + * 1 if a decrement succeeded. + * + * If a completion is being used as a counting completion, + * attempt to decrement the counter without blocking. This + * enables us to avoid waiting if the resource the completion + * is protecting is not available. + */ +bool try_wait_for_completion(struct completion *x) +{ + int ret = 1; + + spin_lock_irq(&x->wait.lock); + if (!x->done) + ret = 0; + else + x->done--; + spin_unlock_irq(&x->wait.lock); + return ret; +} +EXPORT_SYMBOL(try_wait_for_completion); + +/** + * completion_done - Test to see if a completion has any waiters + * @x: completion structure + * + * Returns: 0 if there are waiters (wait_for_completion() in progress) + * 1 if there are no waiters. + * + */ +bool completion_done(struct completion *x) +{ + int ret = 1; + + spin_lock_irq(&x->wait.lock); + if (!x->done) + ret = 0; + spin_unlock_irq(&x->wait.lock); + return ret; +} +EXPORT_SYMBOL(completion_done); + static long __sched sleep_on_common(wait_queue_head_t *q, int state, long timeout) { @@ -5734,6 +5780,8 @@ static inline void sched_init_granularity(void) sysctl_sched_latency = limit; sysctl_sched_wakeup_granularity *= factor; + + sysctl_sched_shares_ratelimit *= factor; } #ifdef CONFIG_SMP @@ -8456,8 +8504,8 @@ struct task_group *sched_create_group(struct task_group *parent) WARN_ON(!parent); /* root should already exist */ tg->parent = parent; - list_add_rcu(&tg->siblings, &parent->children); INIT_LIST_HEAD(&tg->children); + list_add_rcu(&tg->siblings, &parent->children); spin_unlock_irqrestore(&task_group_lock, flags); return tg; |