From 370f0a345a70fe36d0185abf87c7ee8e70572e06 Mon Sep 17 00:00:00 2001 From: Marco Elver Date: Fri, 19 Dec 2025 16:39:59 +0100 Subject: locking/mutex: Support Clang's context analysis Add support for Clang's context analysis for mutex. Signed-off-by: Marco Elver Signed-off-by: Peter Zijlstra (Intel) Link: https://patch.msgid.link/20251219154418.3592607-11-elver@google.com --- include/linux/mutex.h | 38 +++++++++++++++++++++++--------------- include/linux/mutex_types.h | 4 ++-- 2 files changed, 25 insertions(+), 17 deletions(-) (limited to 'include') diff --git a/include/linux/mutex.h b/include/linux/mutex.h index bf535f0118bb..89977c215cbd 100644 --- a/include/linux/mutex.h +++ b/include/linux/mutex.h @@ -62,6 +62,7 @@ do { \ static struct lock_class_key __key; \ \ __mutex_init((mutex), #mutex, &__key); \ + __assume_ctx_lock(mutex); \ } while (0) /** @@ -182,13 +183,13 @@ static inline int __must_check __devm_mutex_init(struct device *dev, struct mute * Also see Documentation/locking/mutex-design.rst. */ #ifdef CONFIG_DEBUG_LOCK_ALLOC -extern void mutex_lock_nested(struct mutex *lock, unsigned int subclass); +extern void mutex_lock_nested(struct mutex *lock, unsigned int subclass) __acquires(lock); extern void _mutex_lock_nest_lock(struct mutex *lock, struct lockdep_map *nest_lock); extern int __must_check mutex_lock_interruptible_nested(struct mutex *lock, - unsigned int subclass); + unsigned int subclass) __cond_acquires(0, lock); extern int __must_check _mutex_lock_killable(struct mutex *lock, - unsigned int subclass, struct lockdep_map *nest_lock); -extern void mutex_lock_io_nested(struct mutex *lock, unsigned int subclass); + unsigned int subclass, struct lockdep_map *nest_lock) __cond_acquires(0, lock); +extern void mutex_lock_io_nested(struct mutex *lock, unsigned int subclass) __acquires(lock); #define mutex_lock(lock) mutex_lock_nested(lock, 0) #define mutex_lock_interruptible(lock) mutex_lock_interruptible_nested(lock, 0) @@ -211,10 +212,10 @@ do { \ _mutex_lock_killable(lock, subclass, NULL) #else -extern void mutex_lock(struct mutex *lock); -extern int __must_check mutex_lock_interruptible(struct mutex *lock); -extern int __must_check mutex_lock_killable(struct mutex *lock); -extern void mutex_lock_io(struct mutex *lock); +extern void mutex_lock(struct mutex *lock) __acquires(lock); +extern int __must_check mutex_lock_interruptible(struct mutex *lock) __cond_acquires(0, lock); +extern int __must_check mutex_lock_killable(struct mutex *lock) __cond_acquires(0, lock); +extern void mutex_lock_io(struct mutex *lock) __acquires(lock); # define mutex_lock_nested(lock, subclass) mutex_lock(lock) # define mutex_lock_interruptible_nested(lock, subclass) mutex_lock_interruptible(lock) @@ -232,7 +233,7 @@ extern void mutex_lock_io(struct mutex *lock); */ #ifdef CONFIG_DEBUG_LOCK_ALLOC -extern int _mutex_trylock_nest_lock(struct mutex *lock, struct lockdep_map *nest_lock); +extern int _mutex_trylock_nest_lock(struct mutex *lock, struct lockdep_map *nest_lock) __cond_acquires(true, lock); #define mutex_trylock_nest_lock(lock, nest_lock) \ ( \ @@ -242,17 +243,24 @@ extern int _mutex_trylock_nest_lock(struct mutex *lock, struct lockdep_map *nest #define mutex_trylock(lock) _mutex_trylock_nest_lock(lock, NULL) #else -extern int mutex_trylock(struct mutex *lock); +extern int mutex_trylock(struct mutex *lock) __cond_acquires(true, lock); #define mutex_trylock_nest_lock(lock, nest_lock) mutex_trylock(lock) #endif -extern void mutex_unlock(struct mutex *lock); +extern void mutex_unlock(struct mutex *lock) __releases(lock); -extern int atomic_dec_and_mutex_lock(atomic_t *cnt, struct mutex *lock); +extern int atomic_dec_and_mutex_lock(atomic_t *cnt, struct mutex *lock) __cond_acquires(true, lock); -DEFINE_GUARD(mutex, struct mutex *, mutex_lock(_T), mutex_unlock(_T)) -DEFINE_GUARD_COND(mutex, _try, mutex_trylock(_T)) -DEFINE_GUARD_COND(mutex, _intr, mutex_lock_interruptible(_T), _RET == 0) +DEFINE_LOCK_GUARD_1(mutex, struct mutex, mutex_lock(_T->lock), mutex_unlock(_T->lock)) +DEFINE_LOCK_GUARD_1_COND(mutex, _try, mutex_trylock(_T->lock)) +DEFINE_LOCK_GUARD_1_COND(mutex, _intr, mutex_lock_interruptible(_T->lock), _RET == 0) + +DECLARE_LOCK_GUARD_1_ATTRS(mutex, __acquires(_T), __releases(*(struct mutex **)_T)) +#define class_mutex_constructor(_T) WITH_LOCK_GUARD_1_ATTRS(mutex, _T) +DECLARE_LOCK_GUARD_1_ATTRS(mutex_try, __acquires(_T), __releases(*(struct mutex **)_T)) +#define class_mutex_try_constructor(_T) WITH_LOCK_GUARD_1_ATTRS(mutex_try, _T) +DECLARE_LOCK_GUARD_1_ATTRS(mutex_intr, __acquires(_T), __releases(*(struct mutex **)_T)) +#define class_mutex_intr_constructor(_T) WITH_LOCK_GUARD_1_ATTRS(mutex_intr, _T) extern unsigned long mutex_get_owner(struct mutex *lock); diff --git a/include/linux/mutex_types.h b/include/linux/mutex_types.h index fdf7f515fde8..80975935ec48 100644 --- a/include/linux/mutex_types.h +++ b/include/linux/mutex_types.h @@ -38,7 +38,7 @@ * - detects multi-task circular deadlocks and prints out all affected * locks and tasks (and only those tasks) */ -struct mutex { +context_lock_struct(mutex) { atomic_long_t owner; raw_spinlock_t wait_lock; #ifdef CONFIG_MUTEX_SPIN_ON_OWNER @@ -59,7 +59,7 @@ struct mutex { */ #include -struct mutex { +context_lock_struct(mutex) { struct rt_mutex_base rtmutex; #ifdef CONFIG_DEBUG_LOCK_ALLOC struct lockdep_map dep_map; -- cgit v1.2.3