spinlock: Indicate that a lockup is only suspected

On an over-committed KVM system we got a:

  "BUG: spinlock lockup on CPU#2, swapper/2/0"

message on the heavily contended virtio blk spinlock.

While we might want to reconsider the locking of virtio-blk
(lock is held while switching to the host) this patch tries to
make the message clearer: the lockup is only suspected.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1338283124-7063-1-git-send-email-borntraeger@de.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Christian Borntraeger 2012-05-29 11:18:44 +02:00 committed by Ingo Molnar
parent c7f5f4ab10
commit 8a173b1476

View File

@ -118,7 +118,7 @@ static void __spin_lock_debug(raw_spinlock_t *lock)
/* lockup suspected: */
if (print_once) {
print_once = 0;
spin_dump(lock, "lockup");
spin_dump(lock, "lockup suspected");
#ifdef CONFIG_SMP
trigger_all_cpu_backtrace();
#endif