| 1 | |
| 2 | * Mutexes: blocking mutual exclusion locks
|
| 3 | *
|
| 4 | * started by Ingo Molnar:
|
| 5 | *
|
| 6 | * Copyright (C) 2004, 2005, 2006 Red Hat, Inc., Ingo Molnar <[email protected]>
|
| 7 | *
|
| 8 | * This file contains mutex debugging related internal prototypes, for the
|
| 9 | * !CONFIG_DEBUG_MUTEXES case. Most of them are NOPs:
|
| 10 |
|
| 11 |
|
| 12 | #define spin_lock_mutex(lock, flags) \
|
| 13 | do { spin_lock(lock); (void)(flags); } while (0)
|
| 14 | #define spin_unlock_mutex(lock, flags) \
|
| 15 | do { spin_unlock(lock); (void)(flags); } while (0)
|
| 16 | #define mutex_remove_waiter(lock, waiter, task) \
|
| 17 | __list_del((waiter)->list.prev, (waiter)->list.next)
|
| 18 |
|
| 19 | #ifdef CONFIG_MUTEX_SPIN_ON_OWNER
|
| 20 | |
| 21 | * The mutex owner can get read and written to locklessly.
|
| 22 | * We should use WRITE_ONCE when writing the owner value to
|
| 23 | * avoid store tearing, otherwise, a thread could potentially
|
| 24 | * read a partially written and incomplete owner value.
|
| 25 |
|
| 26 | static inline void mutex_set_owner(struct mutex *lock)
|
| 27 | {
|
| 28 | WRITE_ONCE(lock->owner, current);
|
| 29 | }
|
| 30 |
|
| 31 | static inline void mutex_clear_owner(struct mutex *lock)
|
| 32 | {
|
| 33 | WRITE_ONCE(lock->owner, NULL);
|
| 34 | }
|
| 35 | #else
|
| 36 | static inline void mutex_set_owner(struct mutex *lock)
|
| 37 | {
|
| 38 | }
|
| 39 |
|
| 40 | static inline void mutex_clear_owner(struct mutex *lock)
|
| 41 | {
|
| 42 | }
|
| 43 | #endif
|
| 44 |
|
| 45 | #define debug_mutex_wake_waiter(lock, waiter) do { } while (0)
|
| 46 | #define debug_mutex_free_waiter(waiter) do { } while (0)
|
| 47 | #define debug_mutex_add_waiter(lock, waiter, ti) do { } while (0)
|
| 48 | #define debug_mutex_unlock(lock) do { } while (0)
|
| 49 | #define debug_mutex_init(lock, name, key) do { } while (0)
|
| 50 |
|
| 51 | static inline void
|
| 52 | debug_mutex_lock_common(struct mutex *lock, struct mutex_waiter *waiter)
|
| 53 | {
|
| 54 | }
|