locking/rtmutex: Use rt_mutex_wake_q_head

Prepare for the required state aware handling of waiter wakeups via wake_q
and switch the rtmutex code over to the rtmutex specific wrapper.

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20210815211303.197113263@linutronix.de

diff --git a/kernel/futex.c b/kernel/futex.c
index 6eab247..21625cb 100644 (file)
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -1493,11 +1493,11 @@ static void mark_wake_futex(struct wake_q_head *wake_q, struct futex_q *q)
  */
 static int wake_futex_pi(u32 __user *uaddr, u32 uval, struct futex_pi_state *pi_state)
 {
-       u32 curval, newval;
        struct rt_mutex_waiter *top_waiter;
        struct task_struct *new_owner;
        bool postunlock = false;
-       DEFINE_WAKE_Q(wake_q);
+       DEFINE_RT_WAKE_Q(wqh);
+       u32 curval, newval;
        int ret = 0;
 
        top_waiter = rt_mutex_top_waiter(&pi_state->pi_mutex);
@@ -1549,14 +1549,14 @@ static int wake_futex_pi(u32 __user *uaddr, u32 uval, struct futex_pi_state *pi_
                 * not fail.
                 */
                pi_state_update_owner(pi_state, new_owner);
-               postunlock = __rt_mutex_futex_unlock(&pi_state->pi_mutex, &wake_q);
+               postunlock = __rt_mutex_futex_unlock(&pi_state->pi_mutex, &wqh);
        }
 
 out_unlock:
        raw_spin_unlock_irq(&pi_state->pi_mutex.wait_lock);
 
        if (postunlock)
-               rt_mutex_postunlock(&wake_q);
+               rt_mutex_postunlock(&wqh);
 
        return ret;
 }

diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c
index 35f7685..5f0d072 100644 (file)
--- a/kernel/locking/rtmutex.c
+++ b/kernel/locking/rtmutex.c
@@ -1017,7 +1017,7 @@ static int __sched task_blocks_on_rt_mutex(struct rt_mutex_base *lock,
  *
  * Called with lock->wait_lock held and interrupts disabled.
  */
-static void __sched mark_wakeup_next_waiter(struct wake_q_head *wake_q,
+static void __sched mark_wakeup_next_waiter(struct rt_wake_q_head *wqh,
                                            struct rt_mutex_base *lock)
 {
        struct rt_mutex_waiter *waiter;
@@ -1054,10 +1054,10 @@ static void __sched mark_wakeup_next_waiter(struct wake_q_head *wake_q,
         * deboost but before waking our donor task, hence the preempt_disable()
         * before unlock.
         *
-        * Pairs with preempt_enable() in rt_mutex_postunlock();
+        * Pairs with preempt_enable() in rt_mutex_wake_up_q();
         */
        preempt_disable();
-       wake_q_add(wake_q, waiter->task);
+       rt_mutex_wake_q_add(wqh, waiter);
        raw_spin_unlock(&current->pi_lock);
 }
 
@@ -1328,7 +1328,7 @@ static __always_inline int __rt_mutex_trylock(struct rt_mutex_base *lock)
  */
 static void __sched rt_mutex_slowunlock(struct rt_mutex_base *lock)
 {
-       DEFINE_WAKE_Q(wake_q);
+       DEFINE_RT_WAKE_Q(wqh);
        unsigned long flags;
 
        /* irqsave required to support early boot calls */
@@ -1381,10 +1381,10 @@ static void __sched rt_mutex_slowunlock(struct rt_mutex_base *lock)
         *
         * Queue the next waiter for wakeup once we release the wait_lock.
         */
-       mark_wakeup_next_waiter(&wake_q, lock);
+       mark_wakeup_next_waiter(&wqh, lock);
        raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
 
-       rt_mutex_postunlock(&wake_q);
+       rt_mutex_wake_up_q(&wqh);
 }
 
 static __always_inline void __rt_mutex_unlock(struct rt_mutex_base *lock)

diff --git a/kernel/locking/rtmutex_api.c b/kernel/locking/rtmutex_api.c
index c5136f4..56403dc 100644 (file)
--- a/kernel/locking/rtmutex_api.c
+++ b/kernel/locking/rtmutex_api.c
@@ -137,10 +137,10 @@ int __sched __rt_mutex_futex_trylock(struct rt_mutex_base *lock)
  * do not use the fast-path, can be simple and will not need to retry.
  *
  * @lock:      The rt_mutex to be unlocked
- * @wake_q:    The wake queue head from which to get the next lock waiter
+ * @wqh:       The wake queue head from which to get the next lock waiter
  */
 bool __sched __rt_mutex_futex_unlock(struct rt_mutex_base *lock,
-                                    struct wake_q_head *wake_q)
+                                    struct rt_wake_q_head *wqh)
 {
        lockdep_assert_held(&lock->wait_lock);
 
@@ -157,23 +157,23 @@ bool __sched __rt_mutex_futex_unlock(struct rt_mutex_base *lock,
         * avoid inversion prior to the wakeup.  preempt_disable()
         * therein pairs with rt_mutex_postunlock().
         */
-       mark_wakeup_next_waiter(wake_q, lock);
+       mark_wakeup_next_waiter(wqh, lock);
 
        return true; /* call postunlock() */
 }
 
 void __sched rt_mutex_futex_unlock(struct rt_mutex_base *lock)
 {
-       DEFINE_WAKE_Q(wake_q);
+       DEFINE_RT_WAKE_Q(wqh);
        unsigned long flags;
        bool postunlock;
 
        raw_spin_lock_irqsave(&lock->wait_lock, flags);
-       postunlock = __rt_mutex_futex_unlock(lock, &wake_q);
+       postunlock = __rt_mutex_futex_unlock(lock, &wqh);
        raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
 
        if (postunlock)
-               rt_mutex_postunlock(&wake_q);
+               rt_mutex_postunlock(&wqh);
 }
 
 /**
@@ -441,12 +441,9 @@ void __sched rt_mutex_adjust_pi(struct task_struct *task)
 /*
  * Performs the wakeup of the top-waiter and re-enables preemption.
  */
-void __sched rt_mutex_postunlock(struct wake_q_head *wake_q)
+void __sched rt_mutex_postunlock(struct rt_wake_q_head *wqh)
 {
-       wake_up_q(wake_q);
-
-       /* Pairs with preempt_disable() in mark_wakeup_next_waiter() */
-       preempt_enable();
+       rt_mutex_wake_up_q(wqh);
 }
 
 #ifdef CONFIG_DEBUG_RT_MUTEXES

diff --git a/kernel/locking/rtmutex_common.h b/kernel/locking/rtmutex_common.h
index 9e2f1db..ff36316 100644 (file)
--- a/kernel/locking/rtmutex_common.h
+++ b/kernel/locking/rtmutex_common.h
@@ -76,9 +76,9 @@ extern int __rt_mutex_futex_trylock(struct rt_mutex_base *l);
 
 extern void rt_mutex_futex_unlock(struct rt_mutex_base *lock);
 extern bool __rt_mutex_futex_unlock(struct rt_mutex_base *lock,
-                               struct wake_q_head *wake_q);
+                               struct rt_wake_q_head *wqh);
 
-extern void rt_mutex_postunlock(struct wake_q_head *wake_q);
+extern void rt_mutex_postunlock(struct rt_wake_q_head *wqh);
 
 /*
  * Must be guarded because this header is included from rcu/tree_plugin.h