Re: [patch] lock debugging: fix DEBUG_LOCKS_WARN_ON() & debug_locks_silent

[Ingo Molnar <mingo@elte.hu>]

* Jarek Poplawski <jarkao2@o2.pl> wrote:

> >  	if (unlikely(c)) {						\
> > -		if (debug_locks_silent || debug_locks_off())		\
> > +		if (!debug_locks_silent && debug_locks_off())		\

btw., updated patch is below - the right order is to first do 
debug_locks_off(), then debug_locks_silent.

[ btw., could you fix your mailer so that a reply to your mails doesnt 
  put all participants into the 'To:' line? You can do it via adding 
  "unset followup_to" to your $HOME/.muttrc file. ]

------------->
Subject: [patch] lock debugging: fix DEBUG_LOCKS_WARN_ON() & debug_locks_silent
From: Ingo Molnar <mingo@elte.hu>

Matthew Wilcox noticed that the debug_locks_silent use should be
inverted in DEBUG_LOCKS_WARN_ON(). This bug was causing spurious
stacktraces and incorrect failures in the locking self-test on the
parisc kernel.

Bug-found-by: Matthew Wilcox <matthew@wil.cx>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 include/linux/debug_locks.h |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Index: linux/include/linux/debug_locks.h
===================================================================
--- linux.orig/include/linux/debug_locks.h
+++ linux/include/linux/debug_locks.h
@@ -24,7 +24,7 @@ extern int debug_locks_off(void);
 	int __ret = 0;							\
 									\
 	if (unlikely(c)) {						\
-		if (debug_locks_silent || debug_locks_off())		\
+		if (debug_locks_off() && !debug_locks_silent)		\
 			WARN_ON(1);					\
 		__ret = 1;						\
 	}								\