locking/mutex: Make __mutex_owner static to mutex.c

__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 <mojha@codeaurora.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: mingo@redhat.com
Cc: will@kernel.org
Link: https://lkml.kernel.org/r/1564585504-3543-1-git-send-email-mojha@codeaurora.org
This commit is contained in:
Mukesh Ojha 2019-07-31 20:35:03 +05:30 committed by Peter Zijlstra
parent 24a376d651
commit 5f35d5a66b
3 changed files with 44 additions and 35 deletions

View File

@ -65,29 +65,6 @@ struct mutex {
#endif #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 #ifdef CONFIG_DEBUG_MUTEXES
#define __DEBUG_MUTEX_INITIALIZER(lockname) \ #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. * Returns true if the mutex is locked, false if unlocked.
*/ */
static inline bool mutex_is_locked(struct mutex *lock) extern bool mutex_is_locked(struct mutex *lock);
{
return __mutex_owner(lock) != NULL;
}
/* /*
* See kernel/locking/mutex.c for detailed documentation of these APIs. * 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_SUCCESS - lock acquired,
* - MUTEX_TRYLOCK_RECURSIVE - we already owned the lock. * - MUTEX_TRYLOCK_RECURSIVE - we already owned the lock.
*/ */
static inline /* __deprecated */ __must_check enum mutex_trylock_recursive_enum extern /* __deprecated */ __must_check enum mutex_trylock_recursive_enum
mutex_trylock_recursive(struct mutex *lock) mutex_trylock_recursive(struct mutex *lock);
{
if (unlikely(__mutex_owner(lock) == current))
return MUTEX_TRYLOCK_RECURSIVE;
return mutex_trylock(lock);
}
#endif /* __LINUX_MUTEX_H */ #endif /* __LINUX_MUTEX_H */

View File

@ -36,6 +36,19 @@
# include "mutex.h" # include "mutex.h"
#endif #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 void
__mutex_init(struct mutex *lock, const char *name, struct lock_class_key *key) __mutex_init(struct mutex *lock, const char *name, struct lock_class_key *key)
{ {
@ -65,11 +78,37 @@ EXPORT_SYMBOL(__mutex_init);
#define MUTEX_FLAGS 0x07 #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) static inline struct task_struct *__owner_task(unsigned long owner)
{ {
return (struct task_struct *)(owner & ~MUTEX_FLAGS); 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) static inline unsigned long __owner_flags(unsigned long owner)
{ {
return owner & MUTEX_FLAGS; return owner & MUTEX_FLAGS;

View File

@ -19,6 +19,8 @@
#define debug_mutex_unlock(lock) do { } while (0) #define debug_mutex_unlock(lock) do { } while (0)
#define debug_mutex_init(lock, name, key) do { } while (0) #define debug_mutex_init(lock, name, key) do { } while (0)
struct mutex_waiter;
static inline void static inline void
debug_mutex_lock_common(struct mutex *lock, struct mutex_waiter *waiter) debug_mutex_lock_common(struct mutex *lock, struct mutex_waiter *waiter)
{ {