futex,rt_mutex: Introduce rt_mutex_init_waiter()

[ Upstream commit 50809358dd7199aa7ce232f6877dd09ec30ef374 ]

Since there's already two copies of this code, introduce a helper now
before adding a third one.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: juri.lelli@arm.com
Cc: bigeasy@linutronix.de
Cc: xlpang@redhat.com
Cc: rostedt@goodmis.org
Cc: mathieu.desnoyers@efficios.com
Cc: jdesfossez@efficios.com
Cc: dvhart@infradead.org
Cc: bristot@redhat.com
Link: http://lkml.kernel.org/r/20170322104151.950039479@infradead.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Acked-by: Joe Korty <joe.korty@concurrent-rt.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/kernel/futex.c b/kernel/futex.c
index dab9c79a931a23ed8677b0c48c334b620d88dbfb..53a085a378f3844d481b4add9a7cd2d0206cf782 100644 (file)
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -3156,10 +3156,7 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
         * The waiter is allocated on our stack, manipulated by the requeue
         * code while we sleep on uaddr.
         */
-       debug_rt_mutex_init_waiter(&rt_waiter);
-       RB_CLEAR_NODE(&rt_waiter.pi_tree_entry);
-       RB_CLEAR_NODE(&rt_waiter.tree_entry);
-       rt_waiter.task = NULL;
+       rt_mutex_init_waiter(&rt_waiter);
 
        ret = get_futex_key(uaddr2, flags & FLAGS_SHARED, &key2, VERIFY_WRITE);
        if (unlikely(ret != 0))

diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c
index 1c0cb5c3c6ad6fe3773a5b2eb48b2058caac175e..fa24df4bc7a8ff0e061263a2ba06c8c4ccaa836f 100644 (file)
--- a/kernel/locking/rtmutex.c
+++ b/kernel/locking/rtmutex.c
@@ -1155,6 +1155,14 @@ void rt_mutex_adjust_pi(struct task_struct *task)
                                   next_lock, NULL, task);
 }
 
+void rt_mutex_init_waiter(struct rt_mutex_waiter *waiter)
+{
+       debug_rt_mutex_init_waiter(waiter);
+       RB_CLEAR_NODE(&waiter->pi_tree_entry);
+       RB_CLEAR_NODE(&waiter->tree_entry);
+       waiter->task = NULL;
+}
+
 /**
  * __rt_mutex_slowlock() - Perform the wait-wake-try-to-take loop
  * @lock:               the rt_mutex to take
@@ -1236,9 +1244,7 @@ rt_mutex_slowlock(struct rt_mutex *lock, int state,
        struct rt_mutex_waiter waiter;
        int ret = 0;
 
-       debug_rt_mutex_init_waiter(&waiter);
-       RB_CLEAR_NODE(&waiter.pi_tree_entry);
-       RB_CLEAR_NODE(&waiter.tree_entry);
+       rt_mutex_init_waiter(&waiter);
 
        raw_spin_lock(&lock->wait_lock);
 

diff --git a/kernel/locking/rtmutex_common.h b/kernel/locking/rtmutex_common.h
index 4584db96265d429da8175a07e1f408da7d75a538..0424ff97bb69cad6dddf42c2f5480797ee48710a 100644 (file)
--- a/kernel/locking/rtmutex_common.h
+++ b/kernel/locking/rtmutex_common.h
@@ -102,6 +102,7 @@ extern struct task_struct *rt_mutex_next_owner(struct rt_mutex *lock);
 extern void rt_mutex_init_proxy_locked(struct rt_mutex *lock,
                                       struct task_struct *proxy_owner);
 extern void rt_mutex_proxy_unlock(struct rt_mutex *lock);
+extern void rt_mutex_init_waiter(struct rt_mutex_waiter *waiter);
 extern int rt_mutex_start_proxy_lock(struct rt_mutex *lock,
                                     struct rt_mutex_waiter *waiter,
                                     struct task_struct *task);