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| author | Frederic Weisbecker <fweisbec@gmail.com> | 2009-07-16 13:44:29 (GMT) |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2009-07-18 13:51:42 (GMT) |
| commit | e4aafea2d4bde8b44d6500c4ee7195bbfc51269e (patch) | |
| tree | bf0c9df18b9f63bb10da0096d81ba80712a71665 /kernel/sched.c | |
| parent | e09758fae8ccde97e026c704319eaa18d488dc86 (diff) | |
| download | linux-e4aafea2d4bde8b44d6500c4ee7195bbfc51269e.tar.xz | |
sched: Add a preempt count base offset to __might_sleep()
Add a preempt count base offset to compare against the current
preempt level count. It prepares to pull up the might_sleep
check from cond_resched() to cond_resched_lock() and
cond_resched_bh().
For these two helpers, we need to respectively ensure that once
we'll unlock the given spinlock / reenable local softirqs, we
will reach a sleepable state.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
[ Move and rename preempt_count_equals() ]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1247725694-6082-4-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel/sched.c')
| -rw-r--r-- | kernel/sched.c | 15 |
1 files changed, 11 insertions, 4 deletions
diff --git a/kernel/sched.c b/kernel/sched.c index 370a6c3..3ff4d00 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -6610,7 +6610,7 @@ static inline int should_resched(void) static void __cond_resched(void) { - __might_sleep(__FILE__, __LINE__); + __might_sleep(__FILE__, __LINE__, 0); add_preempt_count(PREEMPT_ACTIVE); schedule(); @@ -9429,13 +9429,20 @@ void __init sched_init(void) } #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; |