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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 a6fbb4130521..17d28ce20300 100644
--- a/kernel/rtmutex.c
+++ b/kernel/rtmutex.c
@@ -56,7 +56,7 @@
56 * state. 56 * state.
57 */ 57 */
58 58
59void 59static void
60rt_mutex_set_owner(struct rt_mutex *lock, struct task_struct *owner, 60rt_mutex_set_owner(struct rt_mutex *lock, struct task_struct *owner,
61 unsigned long mask) 61 unsigned long mask)
62{ 62{
@@ -81,6 +81,29 @@ static void fixup_rt_mutex_waiters(struct rt_mutex *lock)
81} 81}
82 82
83/* 83/*
84 * We can speed up the acquire/release, if the architecture
85 * supports cmpxchg and if there's no debugging state to be set up
86 */
87#if defined(__HAVE_ARCH_CMPXCHG) && !defined(CONFIG_DEBUG_RT_MUTEXES)
88# define rt_mutex_cmpxchg(l,c,n) (cmpxchg(&l->owner, c, n) == c)
89static inline void mark_rt_mutex_waiters(struct rt_mutex *lock)
90{
91 unsigned long owner, *p = (unsigned long *) &lock->owner;
92
93 do {
94 owner = *p;
95 } while (cmpxchg(p, owner, owner | RT_MUTEX_HAS_WAITERS) != owner);
96}
97#else
98# define rt_mutex_cmpxchg(l,c,n) (0)
99static inline void mark_rt_mutex_waiters(struct rt_mutex *lock)
100{
101 lock->owner = (struct task_struct *)
102 ((unsigned long)lock->owner | RT_MUTEX_HAS_WAITERS);
103}
104#endif
105
106/*
84 * Calculate task priority from the waiter list priority 107 * Calculate task priority from the waiter list priority
85 * 108 *
86 * Return task->normal_prio when the waiter list is empty or when 109 * Return task->normal_prio when the waiter list is empty or when
@@ -100,7 +123,7 @@ int rt_mutex_getprio(struct task_struct *task)
100 * 123 *
101 * This can be both boosting and unboosting. task->pi_lock must be held. 124 * This can be both boosting and unboosting. task->pi_lock must be held.
102 */ 125 */
103void __rt_mutex_adjust_prio(struct task_struct *task) 126static void __rt_mutex_adjust_prio(struct task_struct *task)
104{ 127{
105 int prio = rt_mutex_getprio(task); 128 int prio = rt_mutex_getprio(task);
106 129
@@ -136,11 +159,11 @@ int max_lock_depth = 1024;
136 * Decreases task's usage by one - may thus free the task. 159 * Decreases task's usage by one - may thus free the task.
137 * Returns 0 or -EDEADLK. 160 * Returns 0 or -EDEADLK.
138 */ 161 */
139int rt_mutex_adjust_prio_chain(struct task_struct *task, 162static int rt_mutex_adjust_prio_chain(struct task_struct *task,
140 int deadlock_detect, 163 int deadlock_detect,
141 struct rt_mutex *orig_lock, 164 struct rt_mutex *orig_lock,
142 struct rt_mutex_waiter *orig_waiter, 165 struct rt_mutex_waiter *orig_waiter,
143 struct task_struct *top_task) 166 struct task_struct *top_task)
144{ 167{
145 struct rt_mutex *lock; 168 struct rt_mutex *lock;
146 struct rt_mutex_waiter *waiter, *top_waiter = orig_waiter; 169 struct rt_mutex_waiter *waiter, *top_waiter = orig_waiter;
@@ -514,8 +537,8 @@ static void wakeup_next_waiter(struct rt_mutex *lock)
514 * 537 *
515 * Must be called with lock->wait_lock held 538 * Must be called with lock->wait_lock held
516 */ 539 */
517void remove_waiter(struct rt_mutex *lock, 540static void remove_waiter(struct rt_mutex *lock,
518 struct rt_mutex_waiter *waiter) 541 struct rt_mutex_waiter *waiter)
519{ 542{
520 int first = (waiter == rt_mutex_top_waiter(lock)); 543 int first = (waiter == rt_mutex_top_waiter(lock));
521 struct task_struct *owner = rt_mutex_owner(lock); 544 struct task_struct *owner = rt_mutex_owner(lock);