No, what I mean is that why can't you do about the same mutexed
activated inside static_key API function instead of requiring every
user to worry about the function returning asynchronously.
ie. synchronize inside static_key API instead of in the callers.
Like this?
diff --git a/kernel/jump_label.c b/kernel/jump_label.c
index 4304919..f7cdc18 100644
--- a/kernel/jump_label.c
+++ b/kernel/jump_label.c
@@ -57,10 +57,11 @@ static void jump_label_update(struct static_key *key, int enable);
void static_key_slow_inc(struct static_key *key)
{
+ jump_label_lock();
+
if (atomic_inc_not_zero(&key->enabled))
- return;
+ goto out;
- jump_label_lock();
if (atomic_read(&key->enabled) == 0) {
if (!jump_label_get_branch_default(key))
jump_label_update(key, JUMP_LABEL_ENABLE);
@@ -68,6 +69,7 @@ void static_key_slow_inc(struct static_key *key)
jump_label_update(key, JUMP_LABEL_DISABLE);
}
atomic_inc(&key->enabled);
+out:
jump_label_unlock();
}
EXPORT_SYMBOL_GPL(static_key_slow_inc);
@@ -75,10 +77,11 @@ EXPORT_SYMBOL_GPL(static_key_slow_inc);
static void __static_key_slow_dec(struct static_key *key,
unsigned long rate_limit, struct delayed_work *work)
{
- if (!atomic_dec_and_mutex_lock(&key->enabled, &jump_label_mutex)) {
+ jump_label_lock();
+ if (atomic_dec_and_test(&key->enabled)) {
WARN(atomic_read(&key->enabled) < 0,
"jump label: negative count!\n");
- return;
+ goto out;
}
if (rate_limit) {
@@ -90,6 +93,8 @@ static void __static_key_slow_dec(struct static_key *key,
else
jump_label_update(key, JUMP_LABEL_ENABLE);
}
+
+out:
jump_label_unlock();
}