xref: /OK3568_Linux_fs/kernel/lib/debug_locks.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-only
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  * lib/debug_locks.c
4*4882a593Smuzhiyun  *
5*4882a593Smuzhiyun  * Generic place for common debugging facilities for various locks:
6*4882a593Smuzhiyun  * spinlocks, rwlocks, mutexes and rwsems.
7*4882a593Smuzhiyun  *
8*4882a593Smuzhiyun  * Started by Ingo Molnar:
9*4882a593Smuzhiyun  *
10*4882a593Smuzhiyun  *  Copyright (C) 2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
11*4882a593Smuzhiyun  */
12*4882a593Smuzhiyun #include <linux/rwsem.h>
13*4882a593Smuzhiyun #include <linux/mutex.h>
14*4882a593Smuzhiyun #include <linux/export.h>
15*4882a593Smuzhiyun #include <linux/spinlock.h>
16*4882a593Smuzhiyun #include <linux/debug_locks.h>
17*4882a593Smuzhiyun 
18*4882a593Smuzhiyun /*
19*4882a593Smuzhiyun  * We want to turn all lock-debugging facilities on/off at once,
20*4882a593Smuzhiyun  * via a global flag. The reason is that once a single bug has been
21*4882a593Smuzhiyun  * detected and reported, there might be cascade of followup bugs
22*4882a593Smuzhiyun  * that would just muddy the log. So we report the first one and
23*4882a593Smuzhiyun  * shut up after that.
24*4882a593Smuzhiyun  */
25*4882a593Smuzhiyun int debug_locks __read_mostly = 1;
26*4882a593Smuzhiyun EXPORT_SYMBOL_GPL(debug_locks);
27*4882a593Smuzhiyun 
28*4882a593Smuzhiyun /*
29*4882a593Smuzhiyun  * The locking-testsuite uses <debug_locks_silent> to get a
30*4882a593Smuzhiyun  * 'silent failure': nothing is printed to the console when
31*4882a593Smuzhiyun  * a locking bug is detected.
32*4882a593Smuzhiyun  */
33*4882a593Smuzhiyun int debug_locks_silent __read_mostly;
34*4882a593Smuzhiyun EXPORT_SYMBOL_GPL(debug_locks_silent);
35*4882a593Smuzhiyun 
36*4882a593Smuzhiyun /*
37*4882a593Smuzhiyun  * Generic 'turn off all lock debugging' function:
38*4882a593Smuzhiyun  */
debug_locks_off(void)39*4882a593Smuzhiyun int debug_locks_off(void)
40*4882a593Smuzhiyun {
41*4882a593Smuzhiyun 	if (debug_locks && __debug_locks_off() && !debug_locks_silent)
42*4882a593Smuzhiyun 		return 1;
43*4882a593Smuzhiyun 	return 0;
44*4882a593Smuzhiyun }
45*4882a593Smuzhiyun EXPORT_SYMBOL_GPL(debug_locks_off);
46