Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull locking updates from Ingo Molnar:

 - Add 'cross-release' support to lockdep, which allows APIs like
   completions, where it's not the 'owner' who releases the lock, to be
   tracked. It's all activated automatically under
   CONFIG_PROVE_LOCKING=y.

 - Clean up (restructure) the x86 atomics op implementation to be more
   readable, in preparation of KASAN annotations. (Dmitry Vyukov)

 - Fix static keys (Paolo Bonzini)

 - Add killable versions of down_read() et al (Kirill Tkhai)

 - Rework and fix jump_label locking (Marc Zyngier, Paolo Bonzini)

 - Rework (and fix) tlb_flush_pending() barriers (Peter Zijlstra)

 - Remove smp_mb__before_spinlock() and convert its usages, introduce
   smp_mb__after_spinlock() (Peter Zijlstra)

* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (56 commits)
  locking/lockdep/selftests: Fix mixed read-write ABBA tests
  sched/completion: Avoid unnecessary stack allocation for COMPLETION_INITIALIZER_ONSTACK()
  acpi/nfit: Fix COMPLETION_INITIALIZER_ONSTACK() abuse
  locking/pvqspinlock: Relax cmpxchg's to improve performance on some architectures
  smp: Avoid using two cache lines for struct call_single_data
  locking/lockdep: Untangle xhlock history save/restore from task independence
  locking/refcounts, x86/asm: Disable CONFIG_ARCH_HAS_REFCOUNT for the time being
  futex: Remove duplicated code and fix undefined behaviour
  Documentation/locking/atomic: Finish the document...
  locking/lockdep: Fix workqueue crossrelease annotation
  workqueue/lockdep: 'Fix' flush_work() annotation
  locking/lockdep/selftests: Add mixed read-write ABBA tests
  mm, locking/barriers: Clarify tlb_flush_pending() barriers
  locking/lockdep: Make CONFIG_LOCKDEP_CROSSRELEASE and CONFIG_LOCKDEP_COMPLETIONS truly non-interactive
  locking/lockdep: Explicitly initialize wq_barrier::done::map
  locking/lockdep: Rename CONFIG_LOCKDEP_COMPLETE to CONFIG_LOCKDEP_COMPLETIONS
  locking/lockdep: Reword title of LOCKDEP_CROSSRELEASE config
  locking/lockdep: Make CONFIG_LOCKDEP_CROSSRELEASE part of CONFIG_PROVE_LOCKING
  locking/refcounts, x86/asm: Implement fast refcount overflow protection
  locking/lockdep: Fix the rollback and overwrite detection logic in crossrelease
  ...

4 files changed, 14 insertions, 9 deletions

diff --git a/kernel/sched/completion.c b/kernel/sched/completion.c
index 5d9131aa846f..cc873075c3bd 100644
--- a/kernel/sched/completion.c
+++ b/kernel/sched/completion.c
@@ -32,6 +32,12 @@ void complete(struct completion *x)
 	unsigned long flags;
 
 	spin_lock_irqsave(&x->wait.lock, flags);
+
+	/*
+	 * Perform commit of crossrelease here.
+	 */
+	complete_release_commit(x);
+
 	if (x->done != UINT_MAX)
 		x->done++;
 	__wake_up_locked(&x->wait, TASK_NORMAL, 1);
@@ -99,9 +105,14 @@ __wait_for_common(struct completion *x,
 {
 	might_sleep();
 
+	complete_acquire(x);
+
 	spin_lock_irq(&x->wait.lock);
 	timeout = do_wait_for_common(x, action, timeout, state);
 	spin_unlock_irq(&x->wait.lock);
+
+	complete_release(x);
+
 	return timeout;
 }
 
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index c1fcd96cf432..6d2c7ff9ba98 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -1972,8 +1972,8 @@ try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags)
 	 * reordered with p->state check below. This pairs with mb() in
 	 * set_current_state() the waiting thread does.
 	 */
-	smp_mb__before_spinlock();
 	raw_spin_lock_irqsave(&p->pi_lock, flags);
+	smp_mb__after_spinlock();
 	if (!(p->state & state))
 		goto out;
 
@@ -3296,8 +3296,8 @@ static void __sched notrace __schedule(bool preempt)
 	 * can't be reordered with __set_current_state(TASK_INTERRUPTIBLE)
 	 * done by the caller to avoid the race with signal_wake_up().
 	 */
-	smp_mb__before_spinlock();
 	rq_lock(rq, &rf);
+	smp_mb__after_spinlock();
 
 	/* Promote REQ to ACT */
 	rq->clock_update_flags <<= 1;
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index 25e5cb1107f3..ab1c7f5409a0 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -769,7 +769,7 @@ struct rq {
 #ifdef CONFIG_SCHED_HRTICK
 #ifdef CONFIG_SMP
 	int hrtick_csd_pending;
-	struct call_single_data hrtick_csd;
+	call_single_data_t hrtick_csd;
 #endif
 	struct hrtimer hrtick_timer;
 #endif
diff --git a/kernel/sched/swait.c b/kernel/sched/swait.c
index 3d5610dcce11..2227e183e202 100644
--- a/kernel/sched/swait.c
+++ b/kernel/sched/swait.c
@@ -33,9 +33,6 @@ void swake_up(struct swait_queue_head *q)
 {
 	unsigned long flags;
 
-	if (!swait_active(q))
-		return;
-
 	raw_spin_lock_irqsave(&q->lock, flags);
 	swake_up_locked(q);
 	raw_spin_unlock_irqrestore(&q->lock, flags);
@@ -51,9 +48,6 @@ void swake_up_all(struct swait_queue_head *q)
 	struct swait_queue *curr;
 	LIST_HEAD(tmp);
 
-	if (!swait_active(q))
-		return;
-
 	raw_spin_lock_irq(&q->lock);
 	list_splice_init(&q->task_list, &tmp);
 	while (!list_empty(&tmp)) {