Commit 8a173b14 authored May 29, 2012 by Christian Borntraeger Committed by Ingo Molnar Jun 06, 2012

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>

parent c7f5f4ab

lib/spinlock_debug.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -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

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