| Ingo Molnar | 23f78d4a | 2006-06-27 02:54:53 -0700 | [diff] [blame] | 1 | /* |
| 2 | * RT Mutexes: blocking mutual exclusion locks with PI support |
| 3 | * |
| 4 | * started by Ingo Molnar and Thomas Gleixner: |
| 5 | * |
| 6 | * Copyright (C) 2004-2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com> |
| 7 | * Copyright (C) 2006, Timesys Corp., Thomas Gleixner <tglx@timesys.com> |
| 8 | * |
| 9 | * This file contains the public data structure and API definitions. |
| 10 | */ |
| 11 | |
| 12 | #ifndef __LINUX_RT_MUTEX_H |
| 13 | #define __LINUX_RT_MUTEX_H |
| 14 | |
| 15 | #include <linux/linkage.h> |
| 16 | #include <linux/plist.h> |
| 17 | #include <linux/spinlock_types.h> |
| 18 | |
| 19 | /* |
| 20 | * The rt_mutex structure |
| 21 | * |
| 22 | * @wait_lock: spinlock to protect the structure |
| 23 | * @wait_list: pilist head to enqueue waiters in priority order |
| 24 | * @owner: the mutex owner |
| 25 | */ |
| 26 | struct rt_mutex { |
| 27 | spinlock_t wait_lock; |
| 28 | struct plist_head wait_list; |
| 29 | struct task_struct *owner; |
| 30 | #ifdef CONFIG_DEBUG_RT_MUTEXES |
| 31 | int save_state; |
| 32 | struct list_head held_list_entry; |
| 33 | unsigned long acquire_ip; |
| 34 | const char *name, *file; |
| 35 | int line; |
| 36 | void *magic; |
| 37 | #endif |
| 38 | }; |
| 39 | |
| 40 | struct rt_mutex_waiter; |
| 41 | struct hrtimer_sleeper; |
| 42 | |
| 43 | #ifdef CONFIG_DEBUG_RT_MUTEXES |
| 44 | # define __DEBUG_RT_MUTEX_INITIALIZER(mutexname) \ |
| 45 | , .name = #mutexname, .file = __FILE__, .line = __LINE__ |
| 46 | # define rt_mutex_init(mutex) __rt_mutex_init(mutex, __FUNCTION__) |
| 47 | extern void rt_mutex_debug_task_free(struct task_struct *tsk); |
| 48 | #else |
| 49 | # define __DEBUG_RT_MUTEX_INITIALIZER(mutexname) |
| 50 | # define rt_mutex_init(mutex) __rt_mutex_init(mutex, NULL) |
| 51 | # define rt_mutex_debug_task_free(t) do { } while (0) |
| 52 | #endif |
| 53 | |
| 54 | #define __RT_MUTEX_INITIALIZER(mutexname) \ |
| 55 | { .wait_lock = SPIN_LOCK_UNLOCKED \ |
| 56 | , .wait_list = PLIST_HEAD_INIT(mutexname.wait_list, mutexname.wait_lock) \ |
| 57 | , .owner = NULL \ |
| 58 | __DEBUG_RT_MUTEX_INITIALIZER(mutexname)} |
| 59 | |
| 60 | #define DEFINE_RT_MUTEX(mutexname) \ |
| 61 | struct rt_mutex mutexname = __RT_MUTEX_INITIALIZER(mutexname) |
| 62 | |
| 63 | /*** |
| 64 | * rt_mutex_is_locked - is the mutex locked |
| 65 | * @lock: the mutex to be queried |
| 66 | * |
| 67 | * Returns 1 if the mutex is locked, 0 if unlocked. |
| 68 | */ |
| 69 | static inline int rt_mutex_is_locked(struct rt_mutex *lock) |
| 70 | { |
| 71 | return lock->owner != NULL; |
| 72 | } |
| 73 | |
| 74 | extern void __rt_mutex_init(struct rt_mutex *lock, const char *name); |
| 75 | extern void rt_mutex_destroy(struct rt_mutex *lock); |
| 76 | |
| 77 | extern void rt_mutex_lock(struct rt_mutex *lock); |
| 78 | extern int rt_mutex_lock_interruptible(struct rt_mutex *lock, |
| 79 | int detect_deadlock); |
| 80 | extern int rt_mutex_timed_lock(struct rt_mutex *lock, |
| 81 | struct hrtimer_sleeper *timeout, |
| 82 | int detect_deadlock); |
| 83 | |
| 84 | extern int rt_mutex_trylock(struct rt_mutex *lock); |
| 85 | |
| 86 | extern void rt_mutex_unlock(struct rt_mutex *lock); |
| 87 | |
| 88 | #ifdef CONFIG_DEBUG_RT_MUTEXES |
| 89 | # define INIT_RT_MUTEX_DEBUG(tsk) \ |
| 90 | .held_list_head = LIST_HEAD_INIT(tsk.held_list_head), \ |
| 91 | .held_list_lock = SPIN_LOCK_UNLOCKED |
| 92 | #else |
| 93 | # define INIT_RT_MUTEX_DEBUG(tsk) |
| 94 | #endif |
| 95 | |
| 96 | #ifdef CONFIG_RT_MUTEXES |
| 97 | # define INIT_RT_MUTEXES(tsk) \ |
| 98 | .pi_waiters = PLIST_HEAD_INIT(tsk.pi_waiters, tsk.pi_lock), \ |
| 99 | INIT_RT_MUTEX_DEBUG(tsk) |
| 100 | #else |
| 101 | # define INIT_RT_MUTEXES(tsk) |
| 102 | #endif |
| 103 | |
| 104 | #endif |