[PATCH] cond_resched_lock() fix
On one path, cond_resched_lock() fails to return true if it dropped the lock.
We think this might be causing the crashes in JBD's log_do_checkpoint().
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/kernel/sched.c b/kernel/sched.c
index 66b2ed7..f12a0c8 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -3755,19 +3755,22 @@
*/
int cond_resched_lock(spinlock_t * lock)
{
+ int ret = 0;
+
if (need_lockbreak(lock)) {
spin_unlock(lock);
cpu_relax();
+ ret = 1;
spin_lock(lock);
}
if (need_resched()) {
_raw_spin_unlock(lock);
preempt_enable_no_resched();
__cond_resched();
+ ret = 1;
spin_lock(lock);
- return 1;
}
- return 0;
+ return ret;
}
EXPORT_SYMBOL(cond_resched_lock);
