diff options
Diffstat (limited to 'include/linux/mutex.h')
| -rw-r--r-- | include/linux/mutex.h | 77 |
1 files changed, 14 insertions, 63 deletions
diff --git a/include/linux/mutex.h b/include/linux/mutex.h index e1c323c7d75b..2bf91b57591b 100644 --- a/include/linux/mutex.h +++ b/include/linux/mutex.h @@ -20,6 +20,7 @@ #include <linux/osq_lock.h> #include <linux/debug_locks.h> #include <linux/cleanup.h> +#include <linux/mutex_types.h> struct device; @@ -33,54 +34,9 @@ struct device; # define __DEP_MAP_MUTEX_INITIALIZER(lockname) #endif -#ifndef CONFIG_PREEMPT_RT - -/* - * Simple, straightforward mutexes with strict semantics: - * - * - only one task can hold the mutex at a time - * - only the owner can unlock the mutex - * - multiple unlocks are not permitted - * - recursive locking is not permitted - * - a mutex object must be initialized via the API - * - a mutex object must not be initialized via memset or copying - * - task may not exit with mutex held - * - memory areas where held locks reside must not be freed - * - held mutexes must not be reinitialized - * - mutexes may not be used in hardware or software interrupt - * contexts such as tasklets and timers - * - * These semantics are fully enforced when DEBUG_MUTEXES is - * enabled. Furthermore, besides enforcing the above rules, the mutex - * debugging code also implements a number of additional features - * that make lock debugging easier and faster: - * - * - uses symbolic names of mutexes, whenever they are printed in debug output - * - point-of-acquire tracking, symbolic lookup of function names - * - list of all locks held in the system, printout of them - * - owner tracking - * - detects self-recursing locks and prints out all relevant info - * - detects multi-task circular deadlocks and prints out all affected - * locks and tasks (and only those tasks) - */ -struct mutex { - atomic_long_t owner; - raw_spinlock_t wait_lock; -#ifdef CONFIG_MUTEX_SPIN_ON_OWNER - struct optimistic_spin_queue osq; /* Spinner MCS lock */ -#endif - struct list_head wait_list; #ifdef CONFIG_DEBUG_MUTEXES - void *magic; -#endif -#ifdef CONFIG_DEBUG_LOCK_ALLOC - struct lockdep_map dep_map; -#endif -}; -#ifdef CONFIG_DEBUG_MUTEXES - -#define __DEBUG_MUTEX_INITIALIZER(lockname) \ +# define __DEBUG_MUTEX_INITIALIZER(lockname) \ , .magic = &lockname extern void mutex_destroy(struct mutex *lock); @@ -108,6 +64,18 @@ do { \ __mutex_init((mutex), #mutex, &__key); \ } while (0) +/** + * mutex_init_with_key - initialize a mutex with a given lockdep key + * @mutex: the mutex to be initialized + * @key: the lockdep key to be associated with the mutex + * + * Initialize the mutex to the unlocked state. + * + * It is not allowed to initialize an already locked mutex. + */ +#define mutex_init_with_key(mutex, key) __mutex_init((mutex), #mutex, (key)) + +#ifndef CONFIG_PREEMPT_RT #define __MUTEX_INITIALIZER(lockname) \ { .owner = ATOMIC_LONG_INIT(0) \ , .wait_lock = __RAW_SPIN_LOCK_UNLOCKED(lockname.wait_lock) \ @@ -133,14 +101,6 @@ extern bool mutex_is_locked(struct mutex *lock); /* * Preempt-RT variant based on rtmutexes. */ -#include <linux/rtmutex.h> - -struct mutex { - struct rt_mutex_base rtmutex; -#ifdef CONFIG_DEBUG_LOCK_ALLOC - struct lockdep_map dep_map; -#endif -}; #define __MUTEX_INITIALIZER(mutexname) \ { \ @@ -153,9 +113,6 @@ struct mutex { extern void __mutex_rt_init(struct mutex *lock, const char *name, struct lock_class_key *key); -extern int mutex_trylock(struct mutex *lock); - -static inline void mutex_destroy(struct mutex *lock) { } #define mutex_is_locked(l) rt_mutex_base_is_locked(&(l)->rtmutex) @@ -165,12 +122,6 @@ do { \ __mutex_rt_init((mutex), name, key); \ } while (0) -#define mutex_init(mutex) \ -do { \ - static struct lock_class_key __key; \ - \ - __mutex_init((mutex), #mutex, &__key); \ -} while (0) #endif /* CONFIG_PREEMPT_RT */ #ifdef CONFIG_DEBUG_MUTEXES |