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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: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Peter 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: Ingo Molnar <mingo@kernel.org>
hifive-unleashed-5.1
Marc Zyngier 2017-08-01 09:02:54 +01:00 committed by Ingo Molnar
parent d0646a6f55
commit b70cecf4b6
1 changed files with 4 additions and 2 deletions
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6
kernel/jump_label.c
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@ -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);