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-rw-r--r--Documentation/DocBook/kernel-locking.tmpl6
-rw-r--r--Documentation/mutex-design.txt3
-rw-r--r--include/linux/mutex.h8
-rw-r--r--kernel/mutex.c23
4 files changed, 23 insertions, 17 deletions
diff --git a/Documentation/DocBook/kernel-locking.tmpl b/Documentation/DocBook/kernel-locking.tmpl
index 0b1a3f97f285..a0d479d1e1dd 100644
--- a/Documentation/DocBook/kernel-locking.tmpl
+++ b/Documentation/DocBook/kernel-locking.tmpl
@@ -1961,6 +1961,12 @@ machines due to caching.
</sect1>
</chapter>
+ <chapter id="apiref">
+ <title>Mutex API reference</title>
+!Iinclude/linux/mutex.h
+!Ekernel/mutex.c
+ </chapter>
+
<chapter id="references">
<title>Further reading</title>
diff --git a/Documentation/mutex-design.txt b/Documentation/mutex-design.txt
index c91ccc0720fa..38c10fd7f411 100644
--- a/Documentation/mutex-design.txt
+++ b/Documentation/mutex-design.txt
@@ -9,7 +9,7 @@ firstly, there's nothing wrong with semaphores. But if the simpler
mutex semantics are sufficient for your code, then there are a couple
of advantages of mutexes:
- - 'struct mutex' is smaller on most architectures: .e.g on x86,
+ - 'struct mutex' is smaller on most architectures: E.g. on x86,
'struct semaphore' is 20 bytes, 'struct mutex' is 16 bytes.
A smaller structure size means less RAM footprint, and better
CPU-cache utilization.
@@ -136,3 +136,4 @@ the APIs of 'struct mutex' have been streamlined:
void mutex_lock_nested(struct mutex *lock, unsigned int subclass);
int mutex_lock_interruptible_nested(struct mutex *lock,
unsigned int subclass);
+ int atomic_dec_and_mutex_lock(atomic_t *cnt, struct mutex *lock);
diff --git a/include/linux/mutex.h b/include/linux/mutex.h
index 878cab4f5fcc..f363bc8fdc74 100644
--- a/include/linux/mutex.h
+++ b/include/linux/mutex.h
@@ -78,6 +78,14 @@ struct mutex_waiter {
# include <linux/mutex-debug.h>
#else
# define __DEBUG_MUTEX_INITIALIZER(lockname)
+/**
+ * mutex_init - initialize the mutex
+ * @mutex: the mutex to be initialized
+ *
+ * Initialize the mutex to unlocked state.
+ *
+ * It is not allowed to initialize an already locked mutex.
+ */
# define mutex_init(mutex) \
do { \
static struct lock_class_key __key; \
diff --git a/kernel/mutex.c b/kernel/mutex.c
index 4c0b7b3e6d2e..200407c1502f 100644
--- a/kernel/mutex.c
+++ b/kernel/mutex.c
@@ -36,15 +36,6 @@
# include <asm/mutex.h>
#endif
-/***
- * mutex_init - initialize the mutex
- * @lock: the mutex to be initialized
- * @key: the lock_class_key for the class; used by mutex lock debugging
- *
- * Initialize the mutex to unlocked state.
- *
- * It is not allowed to initialize an already locked mutex.
- */
void
__mutex_init(struct mutex *lock, const char *name, struct lock_class_key *key)
{
@@ -68,7 +59,7 @@ EXPORT_SYMBOL(__mutex_init);
static __used noinline void __sched
__mutex_lock_slowpath(atomic_t *lock_count);
-/***
+/**
* mutex_lock - acquire the mutex
* @lock: the mutex to be acquired
*
@@ -105,7 +96,7 @@ EXPORT_SYMBOL(mutex_lock);
static __used noinline void __sched __mutex_unlock_slowpath(atomic_t *lock_count);
-/***
+/**
* mutex_unlock - release the mutex
* @lock: the mutex to be released
*
@@ -364,8 +355,8 @@ __mutex_lock_killable_slowpath(atomic_t *lock_count);
static noinline int __sched
__mutex_lock_interruptible_slowpath(atomic_t *lock_count);
-/***
- * mutex_lock_interruptible - acquire the mutex, interruptable
+/**
+ * mutex_lock_interruptible - acquire the mutex, interruptible
* @lock: the mutex to be acquired
*
* Lock the mutex like mutex_lock(), and return 0 if the mutex has
@@ -456,15 +447,15 @@ static inline int __mutex_trylock_slowpath(atomic_t *lock_count)
return prev == 1;
}
-/***
- * mutex_trylock - try acquire the mutex, without waiting
+/**
+ * mutex_trylock - try to acquire the mutex, without waiting
* @lock: the mutex to be acquired
*
* Try to acquire the mutex atomically. Returns 1 if the mutex
* has been acquired successfully, and 0 on contention.
*
* NOTE: this function follows the spin_trylock() convention, so
- * it is negated to the down_trylock() return values! Be careful
+ * it is negated from the down_trylock() return values! Be careful
* about this when converting semaphore users to mutexes.
*
* This function must not be used in interrupt context. The