__mutex_owner() should only be used by the mutex api's. So, to put this restiction let's move the __mutex_owner() function definition from linux/mutex.h to mutex.c file.
There exist functions that uses __mutex_owner() like mutex_is_locked() and mutex_trylock_recursive(), So to keep legacy thing intact move them as well and export them. Move mutex_waiter structure also to keep it private to the file. Signed-off-by: Mukesh Ojha <[email protected]> --- Changes in v3: - Moved mutex_waiter and removed inline from mutex_trylock_recursive() mutex_is_owner(). Changes in v2: - On Peterz suggestion, moved __mutex_owner() to mutex.c to make it static to mutex.c. - Exported mutex_is_owner() and mutex_trylock_recursive() to keep the existing thing intact as there are loadable modules which uses these functions. include/linux/mutex.h | 38 +++----------------------------------- kernel/locking/mutex.c | 39 +++++++++++++++++++++++++++++++++++++++ 2 files changed, 42 insertions(+), 35 deletions(-) diff --git a/include/linux/mutex.h b/include/linux/mutex.h index dcd03fe..eb8c62a 100644 --- a/include/linux/mutex.h +++ b/include/linux/mutex.h @@ -65,29 +65,6 @@ struct mutex { #endif }; -/* - * Internal helper function; C doesn't allow us to hide it :/ - * - * DO NOT USE (outside of mutex code). - */ -static inline struct task_struct *__mutex_owner(struct mutex *lock) -{ - return (struct task_struct *)(atomic_long_read(&lock->owner) & ~0x07); -} - -/* - * This is the control structure for tasks blocked on mutex, - * which resides on the blocked task's kernel stack: - */ -struct mutex_waiter { - struct list_head list; - struct task_struct *task; - struct ww_acquire_ctx *ww_ctx; -#ifdef CONFIG_DEBUG_MUTEXES - void *magic; -#endif -}; - #ifdef CONFIG_DEBUG_MUTEXES #define __DEBUG_MUTEX_INITIALIZER(lockname) \ @@ -144,10 +121,7 @@ extern void __mutex_init(struct mutex *lock, const char *name, * * Returns true if the mutex is locked, false if unlocked. */ -static inline bool mutex_is_locked(struct mutex *lock) -{ - return __mutex_owner(lock) != NULL; -} +extern bool mutex_is_locked(struct mutex *lock); /* * See kernel/locking/mutex.c for detailed documentation of these APIs. @@ -220,13 +194,7 @@ enum mutex_trylock_recursive_enum { * - MUTEX_TRYLOCK_SUCCESS - lock acquired, * - MUTEX_TRYLOCK_RECURSIVE - we already owned the lock. */ -static inline /* __deprecated */ __must_check enum mutex_trylock_recursive_enum -mutex_trylock_recursive(struct mutex *lock) -{ - if (unlikely(__mutex_owner(lock) == current)) - return MUTEX_TRYLOCK_RECURSIVE; - - return mutex_trylock(lock); -} +extern /* __deprecated */ __must_check enum mutex_trylock_recursive_enum +mutex_trylock_recursive(struct mutex *lock); #endif /* __LINUX_MUTEX_H */ diff --git a/kernel/locking/mutex.c b/kernel/locking/mutex.c index 5e06973..ac4929f 100644 --- a/kernel/locking/mutex.c +++ b/kernel/locking/mutex.c @@ -36,6 +36,19 @@ # include "mutex.h" #endif +/* + * This is the control structure for tasks blocked on mutex, + * which resides on the blocked task's kernel stack: + */ +struct mutex_waiter { + struct list_head list; + struct task_struct *task; + struct ww_acquire_ctx *ww_ctx; +#ifdef CONFIG_DEBUG_MUTEXES + void *magic; +#endif +}; + void __mutex_init(struct mutex *lock, const char *name, struct lock_class_key *key) { @@ -65,11 +78,37 @@ #define MUTEX_FLAGS 0x07 +/* + * Internal helper function; C doesn't allow us to hide it :/ + * + * DO NOT USE (outside of mutex code). + */ +static inline struct task_struct *__mutex_owner(struct mutex *lock) +{ + return (struct task_struct *)(atomic_long_read(&lock->owner) & ~0x07); +} + static inline struct task_struct *__owner_task(unsigned long owner) { return (struct task_struct *)(owner & ~MUTEX_FLAGS); } +bool mutex_is_locked(struct mutex *lock) +{ + return __mutex_owner(lock) != NULL; +} +EXPORT_SYMBOL(mutex_is_locked); + +__must_check enum mutex_trylock_recursive_enum +mutex_trylock_recursive(struct mutex *lock) +{ + if (unlikely(__mutex_owner(lock) == current)) + return MUTEX_TRYLOCK_RECURSIVE; + + return mutex_trylock(lock); +} +EXPORT_SYMBOL(mutex_trylock_recursive); + static inline unsigned long __owner_flags(unsigned long owner) { return owner & MUTEX_FLAGS; -- Qualcomm India Private Limited, on behalf of Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project
