diff options
Diffstat (limited to 'tools/perf')
-rw-r--r-- | tools/perf/util/mutex.c | 2 | ||||
-rw-r--r-- | tools/perf/util/mutex.h | 70 |
2 files changed, 67 insertions, 5 deletions
diff --git a/tools/perf/util/mutex.c b/tools/perf/util/mutex.c index 5029237164e5..bca7f0717f35 100644 --- a/tools/perf/util/mutex.c +++ b/tools/perf/util/mutex.c @@ -50,11 +50,13 @@ void mutex_destroy(struct mutex *mtx) } void mutex_lock(struct mutex *mtx) + NO_THREAD_SAFETY_ANALYSIS { CHECK_ERR(pthread_mutex_lock(&mtx->lock)); } void mutex_unlock(struct mutex *mtx) + NO_THREAD_SAFETY_ANALYSIS { CHECK_ERR(pthread_mutex_unlock(&mtx->lock)); } diff --git a/tools/perf/util/mutex.h b/tools/perf/util/mutex.h index cfff32a902d9..40661120cacc 100644 --- a/tools/perf/util/mutex.h +++ b/tools/perf/util/mutex.h @@ -6,10 +6,70 @@ #include <stdbool.h> /* + * A function-like feature checking macro that is a wrapper around + * `__has_attribute`, which is defined by GCC 5+ and Clang and evaluates to a + * nonzero constant integer if the attribute is supported or 0 if not. + */ +#ifdef __has_attribute +#define HAVE_ATTRIBUTE(x) __has_attribute(x) +#else +#define HAVE_ATTRIBUTE(x) 0 +#endif + +#if HAVE_ATTRIBUTE(guarded_by) && HAVE_ATTRIBUTE(pt_guarded_by) && \ + HAVE_ATTRIBUTE(lockable) && HAVE_ATTRIBUTE(exclusive_lock_function) && \ + HAVE_ATTRIBUTE(exclusive_trylock_function) && HAVE_ATTRIBUTE(exclusive_locks_required) && \ + HAVE_ATTRIBUTE(no_thread_safety_analysis) + +/* Documents if a shared field or global variable needs to be protected by a mutex. */ +#define GUARDED_BY(x) __attribute__((guarded_by(x))) + +/* + * Documents if the memory location pointed to by a pointer should be guarded by + * a mutex when dereferencing the pointer. + */ +#define PT_GUARDED_BY(x) __attribute__((pt_guarded_by(x))) + +/* Documents if a type is a lockable type. */ +#define LOCKABLE __attribute__((lockable)) + +/* Documents functions that acquire a lock in the body of a function, and do not release it. */ +#define EXCLUSIVE_LOCK_FUNCTION(...) __attribute__((exclusive_lock_function(__VA_ARGS__))) + +/* + * Documents functions that expect a lock to be held on entry to the function, + * and release it in the body of the function. + */ +#define UNLOCK_FUNCTION(...) __attribute__((unlock_function(__VA_ARGS__))) + +/* Documents functions that try to acquire a lock, and return success or failure. */ +#define EXCLUSIVE_TRYLOCK_FUNCTION(...) \ + __attribute__((exclusive_trylock_function(__VA_ARGS__))) + +/* Documents a function that expects a mutex to be held prior to entry. */ +#define EXCLUSIVE_LOCKS_REQUIRED(...) __attribute__((exclusive_locks_required(__VA_ARGS__))) + +/* Turns off thread safety checking within the body of a particular function. */ +#define NO_THREAD_SAFETY_ANALYSIS __attribute__((no_thread_safety_analysis)) + +#else + +#define GUARDED_BY(x) +#define PT_GUARDED_BY(x) +#define LOCKABLE +#define EXCLUSIVE_LOCK_FUNCTION(...) +#define UNLOCK_FUNCTION(...) +#define EXCLUSIVE_TRYLOCK_FUNCTION(...) +#define EXCLUSIVE_LOCKS_REQUIRED(...) +#define NO_THREAD_SAFETY_ANALYSIS + +#endif + +/* * A wrapper around the mutex implementation that allows perf to error check * usage, etc. */ -struct mutex { +struct LOCKABLE mutex { pthread_mutex_t lock; }; @@ -27,10 +87,10 @@ void mutex_init(struct mutex *mtx); void mutex_init_pshared(struct mutex *mtx); void mutex_destroy(struct mutex *mtx); -void mutex_lock(struct mutex *mtx); -void mutex_unlock(struct mutex *mtx); +void mutex_lock(struct mutex *mtx) EXCLUSIVE_LOCK_FUNCTION(*mtx); +void mutex_unlock(struct mutex *mtx) UNLOCK_FUNCTION(*mtx); /* Tries to acquire the lock and returns true on success. */ -bool mutex_trylock(struct mutex *mtx); +bool mutex_trylock(struct mutex *mtx) EXCLUSIVE_TRYLOCK_FUNCTION(true, *mtx); /* Default initialize the cond struct. */ void cond_init(struct cond *cnd); @@ -41,7 +101,7 @@ void cond_init(struct cond *cnd); void cond_init_pshared(struct cond *cnd); void cond_destroy(struct cond *cnd); -void cond_wait(struct cond *cnd, struct mutex *mtx); +void cond_wait(struct cond *cnd, struct mutex *mtx) EXCLUSIVE_LOCKS_REQUIRED(mtx); void cond_signal(struct cond *cnd); void cond_broadcast(struct cond *cnd); |