From: Peter Zijlstra Date: Wed, 22 Mar 2017 11:35:56 +0100 Subject: [PATCH] futex,rt_mutex: Introduce rt_mutex_init_waiter() Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/4.11/older/patches-4.11.9-rt7.tar.xz 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) 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 Signed-off-by: Sebastian Andrzej Siewior --- kernel/futex.c | 5 +---- kernel/locking/rtmutex.c | 12 +++++++++--- kernel/locking/rtmutex_common.h | 1 + 3 files changed, 11 insertions(+), 7 deletions(-) --- a/kernel/futex.c +++ b/kernel/futex.c @@ -2956,10 +2956,7 @@ static int futex_wait_requeue_pi(u32 __u * 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)) --- a/kernel/locking/rtmutex.c +++ b/kernel/locking/rtmutex.c @@ -1153,6 +1153,14 @@ void rt_mutex_adjust_pi(struct task_stru 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, 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 --- a/kernel/locking/rtmutex_common.h +++ b/kernel/locking/rtmutex_common.h @@ -103,6 +103,7 @@ extern void rt_mutex_init_proxy_locked(s 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);