summaryrefslogtreecommitdiff
path: root/kernel/rtmutex.c
diff options
context:
space:
mode:
authorIngo Molnar <mingo@elte.hu>2006-06-27 09:54:57 (GMT)
committerLinus Torvalds <torvalds@g5.osdl.org>2006-06-28 00:32:47 (GMT)
commit0cdbee9920fb37eb2dc49b860c2b28862d647adc (patch)
treedf33dadb52979d7fadd1b464b14ae797d3838181 /kernel/rtmutex.c
parent61a87122869b6340a63b6f9f84097d3688604b90 (diff)
downloadlinux-3.10-0cdbee9920fb37eb2dc49b860c2b28862d647adc.zip
linux-3.10-0cdbee9920fb37eb2dc49b860c2b28862d647adc.tar.gz
linux-3.10-0cdbee9920fb37eb2dc49b860c2b28862d647adc.tar.bz2
[PATCH] pi-futex: rt mutex futex api
Add proxy-locking rt-mutex functionality needed by pi-futexes. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'kernel/rtmutex.c')
-rw-r--r--kernel/rtmutex.c55
1 files changed, 55 insertions, 0 deletions
diff --git a/kernel/rtmutex.c b/kernel/rtmutex.c
index 39c8ca0..3fc0f06 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;
+}