diff options
Diffstat (limited to 'kernel/include/linux/rtmutex.h')
| -rw-r--r-- | kernel/include/linux/rtmutex.h | 117 |
1 files changed, 117 insertions, 0 deletions
diff --git a/kernel/include/linux/rtmutex.h b/kernel/include/linux/rtmutex.h new file mode 100644 index 000000000..d5a04ea47 --- /dev/null +++ b/kernel/include/linux/rtmutex.h @@ -0,0 +1,117 @@ +/* + * RT Mutexes: blocking mutual exclusion locks with PI support + * + * started by Ingo Molnar and Thomas Gleixner: + * + * Copyright (C) 2004-2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com> + * Copyright (C) 2006, Timesys Corp., Thomas Gleixner <tglx@timesys.com> + * + * This file contains the public data structure and API definitions. + */ + +#ifndef __LINUX_RT_MUTEX_H +#define __LINUX_RT_MUTEX_H + +#include <linux/linkage.h> +#include <linux/rbtree.h> +#include <linux/spinlock_types_raw.h> + +extern int max_lock_depth; /* for sysctl */ + +#ifdef CONFIG_DEBUG_MUTEXES +#include <linux/debug_locks.h> +#endif + +/** + * The rt_mutex structure + * + * @wait_lock: spinlock to protect the structure + * @waiters: rbtree root to enqueue waiters in priority order + * @waiters_leftmost: top waiter + * @owner: the mutex owner + */ +struct rt_mutex { + raw_spinlock_t wait_lock; + struct rb_root waiters; + struct rb_node *waiters_leftmost; + struct task_struct *owner; + int save_state; +#ifdef CONFIG_DEBUG_RT_MUTEXES + const char *name, *file; + int line; + void *magic; +#endif +}; + +struct rt_mutex_waiter; +struct hrtimer_sleeper; + +#ifdef CONFIG_DEBUG_RT_MUTEXES + extern int rt_mutex_debug_check_no_locks_freed(const void *from, + unsigned long len); + extern void rt_mutex_debug_check_no_locks_held(struct task_struct *task); +#else + static inline int rt_mutex_debug_check_no_locks_freed(const void *from, + unsigned long len) + { + return 0; + } +# define rt_mutex_debug_check_no_locks_held(task) do { } while (0) +#endif + +# define rt_mutex_init(mutex) \ + do { \ + raw_spin_lock_init(&(mutex)->wait_lock); \ + __rt_mutex_init(mutex, #mutex); \ + } while (0) + +#ifdef CONFIG_DEBUG_RT_MUTEXES +# define __DEBUG_RT_MUTEX_INITIALIZER(mutexname) \ + , .name = #mutexname, .file = __FILE__, .line = __LINE__ + extern void rt_mutex_debug_task_free(struct task_struct *tsk); +#else +# define __DEBUG_RT_MUTEX_INITIALIZER(mutexname) +# define rt_mutex_debug_task_free(t) do { } while (0) +#endif + +#define __RT_MUTEX_INITIALIZER_PLAIN(mutexname) \ + .wait_lock = __RAW_SPIN_LOCK_UNLOCKED(mutexname.wait_lock) \ + , .waiters = RB_ROOT \ + , .owner = NULL \ + __DEBUG_RT_MUTEX_INITIALIZER(mutexname) + +#define __RT_MUTEX_INITIALIZER(mutexname) \ + { __RT_MUTEX_INITIALIZER_PLAIN(mutexname) } + +#define __RT_MUTEX_INITIALIZER_SAVE_STATE(mutexname) \ + { __RT_MUTEX_INITIALIZER_PLAIN(mutexname) \ + , .save_state = 1 } + +#define DEFINE_RT_MUTEX(mutexname) \ + struct rt_mutex mutexname = __RT_MUTEX_INITIALIZER(mutexname) + +/** + * rt_mutex_is_locked - is the mutex locked + * @lock: the mutex to be queried + * + * Returns 1 if the mutex is locked, 0 if unlocked. + */ +static inline int rt_mutex_is_locked(struct rt_mutex *lock) +{ + return lock->owner != NULL; +} + +extern void __rt_mutex_init(struct rt_mutex *lock, const char *name); +extern void rt_mutex_destroy(struct rt_mutex *lock); + +extern void rt_mutex_lock(struct rt_mutex *lock); +extern int rt_mutex_lock_interruptible(struct rt_mutex *lock); +extern int rt_mutex_lock_killable(struct rt_mutex *lock); +extern int rt_mutex_timed_lock(struct rt_mutex *lock, + struct hrtimer_sleeper *timeout); + +extern int rt_mutex_trylock(struct rt_mutex *lock); + +extern void rt_mutex_unlock(struct rt_mutex *lock); + +#endif |