futex,rt_mutex: Introduce rt_mutex_init_waiter()

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>

diff --git a/kernel/futex.c b/kernel/futex.c
index 3b0aace334a8118ab0024481466dbd5e50f049ad..f03ff63326d7724ce150ad23f2d13f3a37d76b6f 100644 (file)
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -2956,10 +2956,7 @@ 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 7d63bc5dd9b2ee733b68e79c683c853a655d82fb..d2fe4b472b1300cfab11b2809739c0915cacf5dd 100644 (file)
--- a/kernel/locking/rtmutex.c
+++ b/kernel/locking/rtmutex.c
@@ -1153,6 +1153,14 @@ 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
@@ -1235,9 +1243,7 @@ rt_mutex_slowlock(struct rt_mutex *lock, int state,
        unsigned long flags;
        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);
 
        /*
         * Technically we could use raw_spin_[un]lock_irq() here, but this can

diff --git a/kernel/locking/rtmutex_common.h b/kernel/locking/rtmutex_common.h
index af667f61ebcb0f6508efcff8f406c8043404e9c9..10f57d688f1742589fff4ababf5aba8b8f0898ac 100644 (file)
--- a/kernel/locking/rtmutex_common.h
+++ b/kernel/locking/rtmutex_common.h
@@ -103,6 +103,7 @@ 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,
                                  struct task_struct *proxy_owner);
+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);