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-rw-r--r--kernel/rtmutex.c41
1 files changed, 32 insertions, 9 deletions
diff --git a/kernel/rtmutex.c b/kernel/rtmutex.c
index a6fbb41..17d28ce 100644
--- a/kernel/rtmutex.c
+++ b/kernel/rtmutex.c
@@ -56,7 +56,7 @@
* state.
*/
-void
+static void
rt_mutex_set_owner(struct rt_mutex *lock, struct task_struct *owner,
unsigned long mask)
{
@@ -81,6 +81,29 @@ static void fixup_rt_mutex_waiters(struct rt_mutex *lock)
}
/*
+ * We can speed up the acquire/release, if the architecture
+ * supports cmpxchg and if there's no debugging state to be set up
+ */
+#if defined(__HAVE_ARCH_CMPXCHG) && !defined(CONFIG_DEBUG_RT_MUTEXES)
+# define rt_mutex_cmpxchg(l,c,n) (cmpxchg(&l->owner, c, n) == c)
+static inline void mark_rt_mutex_waiters(struct rt_mutex *lock)
+{
+ unsigned long owner, *p = (unsigned long *) &lock->owner;
+
+ do {
+ owner = *p;
+ } while (cmpxchg(p, owner, owner | RT_MUTEX_HAS_WAITERS) != owner);
+}
+#else
+# define rt_mutex_cmpxchg(l,c,n) (0)
+static inline void mark_rt_mutex_waiters(struct rt_mutex *lock)
+{
+ lock->owner = (struct task_struct *)
+ ((unsigned long)lock->owner | RT_MUTEX_HAS_WAITERS);
+}
+#endif
+
+/*
* Calculate task priority from the waiter list priority
*
* Return task->normal_prio when the waiter list is empty or when
@@ -100,7 +123,7 @@ int rt_mutex_getprio(struct task_struct *task)
*
* This can be both boosting and unboosting. task->pi_lock must be held.
*/
-void __rt_mutex_adjust_prio(struct task_struct *task)
+static void __rt_mutex_adjust_prio(struct task_struct *task)
{
int prio = rt_mutex_getprio(task);
@@ -136,11 +159,11 @@ int max_lock_depth = 1024;
* Decreases task's usage by one - may thus free the task.
* Returns 0 or -EDEADLK.
*/
-int rt_mutex_adjust_prio_chain(struct task_struct *task,
- int deadlock_detect,
- struct rt_mutex *orig_lock,
- struct rt_mutex_waiter *orig_waiter,
- struct task_struct *top_task)
+static int rt_mutex_adjust_prio_chain(struct task_struct *task,
+ int deadlock_detect,
+ struct rt_mutex *orig_lock,
+ struct rt_mutex_waiter *orig_waiter,
+ struct task_struct *top_task)
{
struct rt_mutex *lock;
struct rt_mutex_waiter *waiter, *top_waiter = orig_waiter;
@@ -514,8 +537,8 @@ static void wakeup_next_waiter(struct rt_mutex *lock)
*
* Must be called with lock->wait_lock held
*/
-void remove_waiter(struct rt_mutex *lock,
- struct rt_mutex_waiter *waiter)
+static void remove_waiter(struct rt_mutex *lock,
+ struct rt_mutex_waiter *waiter)
{
int first = (waiter == rt_mutex_top_waiter(lock));
struct task_struct *owner = rt_mutex_owner(lock);
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