diff options
| -rw-r--r-- | kernel/rtmutex.c | 55 |
1 files changed, 55 insertions, 0 deletions
diff --git a/kernel/rtmutex.c b/kernel/rtmutex.c index 39c8ca0cf526..3fc0f0680ca2 100644 --- a/kernel/rtmutex.c +++ b/kernel/rtmutex.c @@ -903,3 +903,58 @@ void __rt_mutex_init(struct rt_mutex *lock, const char *name) debug_rt_mutex_init(lock, name); } EXPORT_SYMBOL_GPL(__rt_mutex_init); + +/** + * rt_mutex_init_proxy_locked - initialize and lock a rt_mutex on behalf of a + * proxy owner + * + * @lock: the rt_mutex to be locked + * @proxy_owner:the task to set as owner + * + * No locking. Caller has to do serializing itself + * Special API call for PI-futex support + */ +void rt_mutex_init_proxy_locked(struct rt_mutex *lock, + struct task_struct *proxy_owner) +{ + __rt_mutex_init(lock, NULL); + debug_rt_mutex_proxy_lock(lock, proxy_owner __RET_IP__); + rt_mutex_set_owner(lock, proxy_owner, 0); + rt_mutex_deadlock_account_lock(lock, proxy_owner); +} + +/** + * rt_mutex_proxy_unlock - release a lock on behalf of owner + * + * @lock: the rt_mutex to be locked + * + * No locking. Caller has to do serializing itself + * Special API call for PI-futex support + */ +void rt_mutex_proxy_unlock(struct rt_mutex *lock, + struct task_struct *proxy_owner) +{ + debug_rt_mutex_proxy_unlock(lock); + rt_mutex_set_owner(lock, NULL, 0); + rt_mutex_deadlock_account_unlock(proxy_owner); +} + +/** + * rt_mutex_next_owner - return the next owner of the lock + * + * @lock: the rt lock query + * + * Returns the next owner of the lock or NULL + * + * Caller has to serialize against other accessors to the lock + * itself. + * + * Special API call for PI-futex support + */ +struct task_struct *rt_mutex_next_owner(struct rt_mutex *lock) +{ + if (!rt_mutex_has_waiters(lock)) + return NULL; + + return rt_mutex_top_waiter(lock)->task; +} |