Commit b70cecf4 authored by Marc Zyngier's avatar Marc Zyngier Committed by Ingo Molnar
Browse files

jump_label: Move CPU hotplug locking 



As we're about to rework the locking, let's move the taking and
release of the CPU hotplug lock to locations that will make its
reworking completely obvious.

Signed-off-by: default avatarMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/20170801080257.5056-2-marc.zyngier@arm.com


Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent d0646a6f

kernel/jump_label.c

+4 −2
Original line number Diff line number Diff line
@@ -83,6 +83,7 @@ void static_key_slow_inc(struct static_key *key) 
{

	int v, v1;



	cpus_read_lock();

	STATIC_KEY_CHECK_USE();



	/*
@@ -99,11 +100,12 @@ void static_key_slow_inc(struct static_key *key) 
	 */

	for (v = atomic_read(&key->enabled); v > 0; v = v1) {

		v1 = atomic_cmpxchg(&key->enabled, v, v + 1);

		if (likely(v1 == v))

		if (likely(v1 == v)) {

			cpus_read_unlock();

			return;

		}

	}



	cpus_read_lock();

	jump_label_lock();

	if (atomic_read(&key->enabled) == 0) {

		atomic_set(&key->enabled, -1);