linux-stable/include/linux/debug_locks.h
James Hogan 2c2fea1195 debug_locks.h: make warning more verbose
The WARN_ON(1) in DEBUG_LOCKS_WARN_ON is surprisingly awkward to track
down when it's hit, as it's usually buried in macros, causing multiple
instances to land on the same line number.

This patch makes it more useful by switching to:

    WARN(1, "DEBUG_LOCKS_WARN_ON(%s)", #c);

so that the particular DEBUG_LOCKS_WARN_ON is more easily identified and
grep'd for.  For example:

    WARNING: at kernel/mutex.c:198 _mutex_lock_nested+0x31c/0x380()
    DEBUG_LOCKS_WARN_ON(l->magic != l)

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29 15:54:27 -07:00

75 lines
1.5 KiB
C

#ifndef __LINUX_DEBUG_LOCKING_H
#define __LINUX_DEBUG_LOCKING_H
#include <linux/kernel.h>
#include <linux/atomic.h>
#include <linux/bug.h>
struct task_struct;
extern int debug_locks;
extern int debug_locks_silent;
static inline int __debug_locks_off(void)
{
return xchg(&debug_locks, 0);
}
/*
* Generic 'turn off all lock debugging' function:
*/
extern int debug_locks_off(void);
#define DEBUG_LOCKS_WARN_ON(c) \
({ \
int __ret = 0; \
\
if (!oops_in_progress && unlikely(c)) { \
if (debug_locks_off() && !debug_locks_silent) \
WARN(1, "DEBUG_LOCKS_WARN_ON(%s)", #c); \
__ret = 1; \
} \
__ret; \
})
#ifdef CONFIG_SMP
# define SMP_DEBUG_LOCKS_WARN_ON(c) DEBUG_LOCKS_WARN_ON(c)
#else
# define SMP_DEBUG_LOCKS_WARN_ON(c) do { } while (0)
#endif
#ifdef CONFIG_DEBUG_LOCKING_API_SELFTESTS
extern void locking_selftest(void);
#else
# define locking_selftest() do { } while (0)
#endif
struct task_struct;
#ifdef CONFIG_LOCKDEP
extern void debug_show_all_locks(void);
extern void debug_show_held_locks(struct task_struct *task);
extern void debug_check_no_locks_freed(const void *from, unsigned long len);
extern void debug_check_no_locks_held(struct task_struct *task);
#else
static inline void debug_show_all_locks(void)
{
}
static inline void debug_show_held_locks(struct task_struct *task)
{
}
static inline void
debug_check_no_locks_freed(const void *from, unsigned long len)
{
}
static inline void
debug_check_no_locks_held(struct task_struct *task)
{
}
#endif
#endif