Line data    Source code

       1             : // SPDX-License-Identifier: GPL-2.0-only
       2             : /*
       3             :  * lib/debug_locks.c
       4             :  *
       5             :  * Generic place for common debugging facilities for various locks:
       6             :  * spinlocks, rwlocks, mutexes and rwsems.
       7             :  *
       8             :  * Started by Ingo Molnar:
       9             :  *
      10             :  *  Copyright (C) 2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
      11             :  */
      12             : #include <linux/rwsem.h>
      13             : #include <linux/mutex.h>
      14             : #include <linux/export.h>
      15             : #include <linux/spinlock.h>
      16             : #include <linux/debug_locks.h>
      17             : 
      18             : /*
      19             :  * We want to turn all lock-debugging facilities on/off at once,
      20             :  * via a global flag. The reason is that once a single bug has been
      21             :  * detected and reported, there might be cascade of followup bugs
      22             :  * that would just muddy the log. So we report the first one and
      23             :  * shut up after that.
      24             :  */
      25             : int debug_locks __read_mostly = 1;
      26             : EXPORT_SYMBOL_GPL(debug_locks);
      27             : 
      28             : /*
      29             :  * The locking-testsuite uses <debug_locks_silent> to get a
      30             :  * 'silent failure': nothing is printed to the console when
      31             :  * a locking bug is detected.
      32             :  */
      33             : int debug_locks_silent __read_mostly;
      34             : EXPORT_SYMBOL_GPL(debug_locks_silent);
      35             : 
      36             : /*
      37             :  * Generic 'turn off all lock debugging' function:
      38             :  */
      39           0 : noinstr int debug_locks_off(void)
      40             : {
      41           0 :         if (debug_locks && __debug_locks_off()) {
      42           0 :                 if (!debug_locks_silent) {
      43           0 :                         console_verbose();
      44           0 :                         return 1;
      45             :                 }
      46             :         }
      47             :         return 0;
      48             : }
      49             : EXPORT_SYMBOL_GPL(debug_locks_off);