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 <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: [email protected]
Cc: [email protected]
Link: https://lkml.kernel.org/r/[email protected]

diff --git a/include/linux/mutex.h b/include/linux/mutex.h
index dcd03fee6e019a77c568eca60e5e0be2ae4a013f..eb8c62aba26385153b48769b876c3d4b9544ee12 100644 (file)
--- 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 5e069734363c479d294180864c1b2bd9be9bddb8..ac4929f1e085e7dd4fcb4bc455a7b936b4420289 100644 (file)
--- 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 @@ EXPORT_SYMBOL(__mutex_init);
 
 #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;

diff --git a/kernel/locking/mutex.h b/kernel/locking/mutex.h
index 1c2287d3fa7191589c6d8f0d5f4e67c3282f8dfe..7cde5c6d414e9dc4b2823dca2944e54030df2090 100644 (file)
--- a/kernel/locking/mutex.h
+++ b/kernel/locking/mutex.h
@@ -19,6 +19,8 @@
 #define debug_mutex_unlock(lock)                       do { } while (0)
 #define debug_mutex_init(lock, name, key)              do { } while (0)
 
+struct mutex_waiter;
+
 static inline void
 debug_mutex_lock_common(struct mutex *lock, struct mutex_waiter *waiter)
 {