aha/lib/debug_locks.c
David Miller e0fdace10e debug_locks: set oops_in_progress if we will log messages.
Otherwise lock debugging messages on runqueue locks can deadlock the
system due to the wakeups performed by printk().

Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-01 10:46:43 +02:00

47 lines
1.1 KiB
C

/*
* lib/debug_locks.c
*
* Generic place for common debugging facilities for various locks:
* spinlocks, rwlocks, mutexes and rwsems.
*
* Started by Ingo Molnar:
*
* Copyright (C) 2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
*/
#include <linux/kernel.h>
#include <linux/rwsem.h>
#include <linux/mutex.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/debug_locks.h>
/*
* We want to turn all lock-debugging facilities on/off at once,
* via a global flag. The reason is that once a single bug has been
* detected and reported, there might be cascade of followup bugs
* that would just muddy the log. So we report the first one and
* shut up after that.
*/
int debug_locks = 1;
/*
* The locking-testsuite uses <debug_locks_silent> to get a
* 'silent failure': nothing is printed to the console when
* a locking bug is detected.
*/
int debug_locks_silent;
/*
* Generic 'turn off all lock debugging' function:
*/
int debug_locks_off(void)
{
if (xchg(&debug_locks, 0)) {
if (!debug_locks_silent) {
oops_in_progress = 1;
console_verbose();
return 1;
}
}
return 0;
}