18c2ecf20Sopenharmony_ci// SPDX-License-Identifier: GPL-2.0-only
28c2ecf20Sopenharmony_ci/*
38c2ecf20Sopenharmony_ci * lib/debug_locks.c
48c2ecf20Sopenharmony_ci *
58c2ecf20Sopenharmony_ci * Generic place for common debugging facilities for various locks:
68c2ecf20Sopenharmony_ci * spinlocks, rwlocks, mutexes and rwsems.
78c2ecf20Sopenharmony_ci *
88c2ecf20Sopenharmony_ci * Started by Ingo Molnar:
98c2ecf20Sopenharmony_ci *
108c2ecf20Sopenharmony_ci *  Copyright (C) 2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
118c2ecf20Sopenharmony_ci */
128c2ecf20Sopenharmony_ci#include <linux/rwsem.h>
138c2ecf20Sopenharmony_ci#include <linux/mutex.h>
148c2ecf20Sopenharmony_ci#include <linux/export.h>
158c2ecf20Sopenharmony_ci#include <linux/spinlock.h>
168c2ecf20Sopenharmony_ci#include <linux/debug_locks.h>
178c2ecf20Sopenharmony_ci
188c2ecf20Sopenharmony_ci/*
198c2ecf20Sopenharmony_ci * We want to turn all lock-debugging facilities on/off at once,
208c2ecf20Sopenharmony_ci * via a global flag. The reason is that once a single bug has been
218c2ecf20Sopenharmony_ci * detected and reported, there might be cascade of followup bugs
228c2ecf20Sopenharmony_ci * that would just muddy the log. So we report the first one and
238c2ecf20Sopenharmony_ci * shut up after that.
248c2ecf20Sopenharmony_ci */
258c2ecf20Sopenharmony_ciint debug_locks __read_mostly = 1;
268c2ecf20Sopenharmony_ciEXPORT_SYMBOL_GPL(debug_locks);
278c2ecf20Sopenharmony_ci
288c2ecf20Sopenharmony_ci/*
298c2ecf20Sopenharmony_ci * The locking-testsuite uses <debug_locks_silent> to get a
308c2ecf20Sopenharmony_ci * 'silent failure': nothing is printed to the console when
318c2ecf20Sopenharmony_ci * a locking bug is detected.
328c2ecf20Sopenharmony_ci */
338c2ecf20Sopenharmony_ciint debug_locks_silent __read_mostly;
348c2ecf20Sopenharmony_ciEXPORT_SYMBOL_GPL(debug_locks_silent);
358c2ecf20Sopenharmony_ci
368c2ecf20Sopenharmony_ci/*
378c2ecf20Sopenharmony_ci * Generic 'turn off all lock debugging' function:
388c2ecf20Sopenharmony_ci */
398c2ecf20Sopenharmony_ciint debug_locks_off(void)
408c2ecf20Sopenharmony_ci{
418c2ecf20Sopenharmony_ci	if (debug_locks && __debug_locks_off()) {
428c2ecf20Sopenharmony_ci		if (!debug_locks_silent) {
438c2ecf20Sopenharmony_ci			console_verbose();
448c2ecf20Sopenharmony_ci			return 1;
458c2ecf20Sopenharmony_ci		}
468c2ecf20Sopenharmony_ci	}
478c2ecf20Sopenharmony_ci	return 0;
488c2ecf20Sopenharmony_ci}
498c2ecf20Sopenharmony_ciEXPORT_SYMBOL_GPL(debug_locks_off);
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