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locking: Move the mutex code to kernel/locking/

Peter Zijlstra committed 13 years ago

Commit 01768b41 parent c90423d6 files · +11 −4Browse files

Showing the changes to kernel/locking/mutex-debug.c (1 of 6 files). Show all

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kernel/locking/mutex-debug.c+110−0
@@ -0,0 +1,110 @@
1+/*
2+ * kernel/mutex-debug.c
3+ *
4+ * Debugging code for mutexes
5+ *
6+ * Started by Ingo Molnar:
7+ *
8+ * Copyright (C) 2004, 2005, 2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
9+ *
10+ * lock debugging, locking tree, deadlock detection started by:
11+ *
12+ * Copyright (C) 2004, LynuxWorks, Inc., Igor Manyilov, Bill Huey
13+ * Released under the General Public License (GPL).
14+ */
15+#include <linux/mutex.h>
16+#include <linux/delay.h>
17+#include <linux/export.h>
18+#include <linux/poison.h>
19+#include <linux/sched.h>
20+#include <linux/spinlock.h>
21+#include <linux/kallsyms.h>
22+#include <linux/interrupt.h>
23+#include <linux/debug_locks.h>
24+
25+#include "mutex-debug.h"
26+
27+/*
28+ * Must be called with lock->wait_lock held.
29+ */
30+void debug_mutex_lock_common(struct mutex *lock, struct mutex_waiter *waiter)
31+{
32+ memset(waiter, MUTEX_DEBUG_INIT, sizeof(*waiter));
33+ waiter->magic = waiter;
34+ INIT_LIST_HEAD(&waiter->list);
35+}
36+
37+void debug_mutex_wake_waiter(struct mutex *lock, struct mutex_waiter *waiter)
38+{
39+ SMP_DEBUG_LOCKS_WARN_ON(!spin_is_locked(&lock->wait_lock));
40+ DEBUG_LOCKS_WARN_ON(list_empty(&lock->wait_list));
41+ DEBUG_LOCKS_WARN_ON(waiter->magic != waiter);
42+ DEBUG_LOCKS_WARN_ON(list_empty(&waiter->list));
43+}
44+
45+void debug_mutex_free_waiter(struct mutex_waiter *waiter)
46+{
47+ DEBUG_LOCKS_WARN_ON(!list_empty(&waiter->list));
48+ memset(waiter, MUTEX_DEBUG_FREE, sizeof(*waiter));
49+}
50+
51+void debug_mutex_add_waiter(struct mutex *lock, struct mutex_waiter *waiter,
52+ struct thread_info *ti)
53+{
54+ SMP_DEBUG_LOCKS_WARN_ON(!spin_is_locked(&lock->wait_lock));
55+
56+ /* Mark the current thread as blocked on the lock: */
57+ ti->task->blocked_on = waiter;
58+}
59+
60+void mutex_remove_waiter(struct mutex *lock, struct mutex_waiter *waiter,
61+ struct thread_info *ti)
62+{
63+ DEBUG_LOCKS_WARN_ON(list_empty(&waiter->list));
64+ DEBUG_LOCKS_WARN_ON(waiter->task != ti->task);
65+ DEBUG_LOCKS_WARN_ON(ti->task->blocked_on != waiter);
66+ ti->task->blocked_on = NULL;
67+
68+ list_del_init(&waiter->list);
69+ waiter->task = NULL;
70+}
71+
72+void debug_mutex_unlock(struct mutex *lock)
73+{
74+ if (unlikely(!debug_locks))
75+ return;
76+
77+ DEBUG_LOCKS_WARN_ON(lock->magic != lock);
78+ DEBUG_LOCKS_WARN_ON(lock->owner != current);
79+ DEBUG_LOCKS_WARN_ON(!lock->wait_list.prev && !lock->wait_list.next);
80+ mutex_clear_owner(lock);
81+}
82+
83+void debug_mutex_init(struct mutex *lock, const char *name,
84+ struct lock_class_key *key)
85+{
86+#ifdef CONFIG_DEBUG_LOCK_ALLOC
87+ /*
88+ * Make sure we are not reinitializing a held lock:
89+ */
90+ debug_check_no_locks_freed((void *)lock, sizeof(*lock));
91+ lockdep_init_map(&lock->dep_map, name, key, 0);
92+#endif
93+ lock->magic = lock;
94+}
95+
96+/***
97+ * mutex_destroy - mark a mutex unusable
98+ * @lock: the mutex to be destroyed
99+ *
100+ * This function marks the mutex uninitialized, and any subsequent
101+ * use of the mutex is forbidden. The mutex must not be locked when
102+ * this function is called.
103+ */
104+void mutex_destroy(struct mutex *lock)
105+{
106+ DEBUG_LOCKS_WARN_ON(mutex_is_locked(lock));
107+ lock->magic = NULL;
108+}
109+
110+EXPORT_SYMBOL_GPL(mutex_destroy);