diff options
Diffstat (limited to 'include/linux/ww_mutex.h')
| -rw-r--r-- | include/linux/ww_mutex.h | 87 |
1 files changed, 42 insertions, 45 deletions
diff --git a/include/linux/ww_mutex.h b/include/linux/ww_mutex.h index d7554252404c..bb763085479a 100644 --- a/include/linux/ww_mutex.h +++ b/include/linux/ww_mutex.h @@ -18,6 +18,22 @@ #define __LINUX_WW_MUTEX_H #include <linux/mutex.h> +#include <linux/rtmutex.h> + +#if defined(CONFIG_DEBUG_MUTEXES) || \ + (defined(CONFIG_PREEMPT_RT) && defined(CONFIG_DEBUG_RT_MUTEXES)) +#define DEBUG_WW_MUTEXES +#endif + +#ifndef CONFIG_PREEMPT_RT +#define WW_MUTEX_BASE mutex +#define ww_mutex_base_init(l,n,k) __mutex_init(l,n,k) +#define ww_mutex_base_is_locked(b) mutex_is_locked((b)) +#else +#define WW_MUTEX_BASE rt_mutex +#define ww_mutex_base_init(l,n,k) __rt_mutex_init(l,n,k) +#define ww_mutex_base_is_locked(b) rt_mutex_base_is_locked(&(b)->rtmutex) +#endif struct ww_class { atomic_long_t stamp; @@ -28,16 +44,24 @@ struct ww_class { unsigned int is_wait_die; }; +struct ww_mutex { + struct WW_MUTEX_BASE base; + struct ww_acquire_ctx *ctx; +#ifdef DEBUG_WW_MUTEXES + struct ww_class *ww_class; +#endif +}; + struct ww_acquire_ctx { struct task_struct *task; unsigned long stamp; unsigned int acquired; unsigned short wounded; unsigned short is_wait_die; -#ifdef CONFIG_DEBUG_MUTEXES +#ifdef DEBUG_WW_MUTEXES unsigned int done_acquire; struct ww_class *ww_class; - struct ww_mutex *contending_lock; + void *contending_lock; #endif #ifdef CONFIG_DEBUG_LOCK_ALLOC struct lockdep_map dep_map; @@ -48,56 +72,35 @@ struct ww_acquire_ctx { #endif }; -struct ww_mutex { - struct mutex base; - struct ww_acquire_ctx *ctx; -#ifdef CONFIG_DEBUG_MUTEXES - struct ww_class *ww_class; -#endif -}; - -#ifdef CONFIG_DEBUG_LOCK_ALLOC -# define __WW_CLASS_MUTEX_INITIALIZER(lockname, class) \ - , .ww_class = class -#else -# define __WW_CLASS_MUTEX_INITIALIZER(lockname, class) -#endif - #define __WW_CLASS_INITIALIZER(ww_class, _is_wait_die) \ { .stamp = ATOMIC_LONG_INIT(0) \ , .acquire_name = #ww_class "_acquire" \ , .mutex_name = #ww_class "_mutex" \ , .is_wait_die = _is_wait_die } -#define __WW_MUTEX_INITIALIZER(lockname, class) \ - { .base = __MUTEX_INITIALIZER(lockname.base) \ - __WW_CLASS_MUTEX_INITIALIZER(lockname, class) } - #define DEFINE_WD_CLASS(classname) \ struct ww_class classname = __WW_CLASS_INITIALIZER(classname, 1) #define DEFINE_WW_CLASS(classname) \ struct ww_class classname = __WW_CLASS_INITIALIZER(classname, 0) -#define DEFINE_WW_MUTEX(mutexname, ww_class) \ - struct ww_mutex mutexname = __WW_MUTEX_INITIALIZER(mutexname, ww_class) - /** * ww_mutex_init - initialize the w/w mutex * @lock: the mutex to be initialized * @ww_class: the w/w class the mutex should belong to * * Initialize the w/w mutex to unlocked state and associate it with the given - * class. + * class. Static define macro for w/w mutex is not provided and this function + * is the only way to properly initialize the w/w mutex. * * It is not allowed to initialize an already locked mutex. */ static inline void ww_mutex_init(struct ww_mutex *lock, struct ww_class *ww_class) { - __mutex_init(&lock->base, ww_class->mutex_name, &ww_class->mutex_key); + ww_mutex_base_init(&lock->base, ww_class->mutex_name, &ww_class->mutex_key); lock->ctx = NULL; -#ifdef CONFIG_DEBUG_MUTEXES +#ifdef DEBUG_WW_MUTEXES lock->ww_class = ww_class; #endif } @@ -134,7 +137,7 @@ static inline void ww_acquire_init(struct ww_acquire_ctx *ctx, ctx->acquired = 0; ctx->wounded = false; ctx->is_wait_die = ww_class->is_wait_die; -#ifdef CONFIG_DEBUG_MUTEXES +#ifdef DEBUG_WW_MUTEXES ctx->ww_class = ww_class; ctx->done_acquire = 0; ctx->contending_lock = NULL; @@ -164,7 +167,7 @@ static inline void ww_acquire_init(struct ww_acquire_ctx *ctx, */ static inline void ww_acquire_done(struct ww_acquire_ctx *ctx) { -#ifdef CONFIG_DEBUG_MUTEXES +#ifdef DEBUG_WW_MUTEXES lockdep_assert_held(ctx); DEBUG_LOCKS_WARN_ON(ctx->done_acquire); @@ -181,9 +184,10 @@ static inline void ww_acquire_done(struct ww_acquire_ctx *ctx) */ static inline void ww_acquire_fini(struct ww_acquire_ctx *ctx) { -#ifdef CONFIG_DEBUG_MUTEXES +#ifdef CONFIG_DEBUG_LOCK_ALLOC mutex_release(&ctx->dep_map, _THIS_IP_); - +#endif +#ifdef DEBUG_WW_MUTEXES DEBUG_LOCKS_WARN_ON(ctx->acquired); if (!IS_ENABLED(CONFIG_PROVE_LOCKING)) /* @@ -289,7 +293,7 @@ static inline void ww_mutex_lock_slow(struct ww_mutex *lock, struct ww_acquire_ctx *ctx) { int ret; -#ifdef CONFIG_DEBUG_MUTEXES +#ifdef DEBUG_WW_MUTEXES DEBUG_LOCKS_WARN_ON(!ctx->contending_lock); #endif ret = ww_mutex_lock(lock, ctx); @@ -325,7 +329,7 @@ static inline int __must_check ww_mutex_lock_slow_interruptible(struct ww_mutex *lock, struct ww_acquire_ctx *ctx) { -#ifdef CONFIG_DEBUG_MUTEXES +#ifdef DEBUG_WW_MUTEXES DEBUG_LOCKS_WARN_ON(!ctx->contending_lock); #endif return ww_mutex_lock_interruptible(lock, ctx); @@ -333,17 +337,8 @@ ww_mutex_lock_slow_interruptible(struct ww_mutex *lock, extern void ww_mutex_unlock(struct ww_mutex *lock); -/** - * ww_mutex_trylock - tries to acquire the w/w mutex without acquire context - * @lock: mutex to lock - * - * Trylocks a mutex without acquire context, so no deadlock detection is - * possible. Returns 1 if the mutex has been acquired successfully, 0 otherwise. - */ -static inline int __must_check ww_mutex_trylock(struct ww_mutex *lock) -{ - return mutex_trylock(&lock->base); -} +extern int __must_check ww_mutex_trylock(struct ww_mutex *lock, + struct ww_acquire_ctx *ctx); /*** * ww_mutex_destroy - mark a w/w mutex unusable @@ -355,7 +350,9 @@ static inline int __must_check ww_mutex_trylock(struct ww_mutex *lock) */ static inline void ww_mutex_destroy(struct ww_mutex *lock) { +#ifndef CONFIG_PREEMPT_RT mutex_destroy(&lock->base); +#endif } /** @@ -366,7 +363,7 @@ static inline void ww_mutex_destroy(struct ww_mutex *lock) */ static inline bool ww_mutex_is_locked(struct ww_mutex *lock) { - return mutex_is_locked(&lock->base); + return ww_mutex_base_is_locked(&lock->base); } #endif |