forked from Minki/linux
9a11b49a80
Generic lock debugging:
- generalized lock debugging framework. For example, a bug in one lock
subsystem turns off debugging in all lock subsystems.
- got rid of the caller address passing (__IP__/__IP_DECL__/etc.) from
the mutex/rtmutex debugging code: it caused way too much prototype
hackery, and lockdep will give the same information anyway.
- ability to do silent tests
- check lock freeing in vfree too.
- more finegrained debugging options, to allow distributions to
turn off more expensive debugging features.
There's no separate 'held mutexes' list anymore - but there's a 'held locks'
stack within lockdep, which unifies deadlock detection across all lock
classes. (this is independent of the lockdep validation stuff - lockdep first
checks whether we are holding a lock already)
Here are the current debugging options:
CONFIG_DEBUG_MUTEXES=y
CONFIG_DEBUG_LOCK_ALLOC=y
which do:
config DEBUG_MUTEXES
bool "Mutex debugging, basic checks"
config DEBUG_LOCK_ALLOC
bool "Detect incorrect freeing of live mutexes"
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
46 lines
1.1 KiB
C
46 lines
1.1 KiB
C
/*
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* lib/debug_locks.c
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*
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* Generic place for common debugging facilities for various locks:
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* spinlocks, rwlocks, mutexes and rwsems.
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*
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* Started by Ingo Molnar:
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*
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* Copyright (C) 2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
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*/
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#include <linux/rwsem.h>
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#include <linux/mutex.h>
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#include <linux/module.h>
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#include <linux/spinlock.h>
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#include <linux/debug_locks.h>
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/*
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* We want to turn all lock-debugging facilities on/off at once,
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* via a global flag. The reason is that once a single bug has been
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* detected and reported, there might be cascade of followup bugs
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* that would just muddy the log. So we report the first one and
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* shut up after that.
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*/
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int debug_locks = 1;
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/*
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* The locking-testsuite uses <debug_locks_silent> to get a
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* 'silent failure': nothing is printed to the console when
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* a locking bug is detected.
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*/
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int debug_locks_silent;
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/*
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* Generic 'turn off all lock debugging' function:
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*/
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int debug_locks_off(void)
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{
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if (xchg(&debug_locks, 0)) {
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if (!debug_locks_silent) {
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console_verbose();
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return 1;
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}
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}
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return 0;
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}
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