[PATCH v2 1/4] jump_label: Move cpu hotplug locking
Marc Zyngier
marc.zyngier at arm.com
Tue Aug 1 01:02:54 PDT 2017
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 at arm.com>
---
kernel/jump_label.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/kernel/jump_label.c b/kernel/jump_label.c
index d11c506a6ac3..f11b10091100 100644
--- a/kernel/jump_label.c
+++ b/kernel/jump_label.c
@@ -105,6 +105,7 @@ void static_key_slow_inc(struct static_key *key)
{
int v, v1;
+ cpus_read_lock();
STATIC_KEY_CHECK_USE();
/*
@@ -121,11 +122,12 @@ 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);
--
2.11.0
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