jump_label: Split out code under the hotplug lock (8b7b4128) · Commits · 戴 / test

kernel/jump_label.c

+19 −9

Original line number	Original line	Diff line number	Diff line
	@@ -79,11 +79,10 @@ int static_key_count(struct static_key *key)
	}		}
	EXPORT_SYMBOL_GPL(static_key_count);		EXPORT_SYMBOL_GPL(static_key_count);

	void static_key_slow_inc(struct static_key *key)		static void static_key_slow_inc_cpuslocked(struct static_key *key)
	{		{
	int v, v1;		int v, v1;

	cpus_read_lock();
	STATIC_KEY_CHECK_USE();		STATIC_KEY_CHECK_USE();

	/*		/*
	@@ -100,11 +99,9 @@ void static_key_slow_inc(struct static_key *key)
	*/		*/
	for (v = atomic_read(&key->enabled); v > 0; v = v1) {		for (v = atomic_read(&key->enabled); v > 0; v = v1) {
	v1 = atomic_cmpxchg(&key->enabled, v, v + 1);		v1 = atomic_cmpxchg(&key->enabled, v, v + 1);
	if (likely(v1 == v)) {		if (likely(v1 == v))
	cpus_read_unlock();
	return;		return;
	}		}
	}

	jump_label_lock();		jump_label_lock();
	if (atomic_read(&key->enabled) == 0) {		if (atomic_read(&key->enabled) == 0) {
	@@ -119,6 +116,12 @@ void static_key_slow_inc(struct static_key *key)
	atomic_inc(&key->enabled);		atomic_inc(&key->enabled);
	}		}
	jump_label_unlock();		jump_label_unlock();
			}

			void static_key_slow_inc(struct static_key *key)
			{
			cpus_read_lock();
			static_key_slow_inc_cpuslocked(key);
	cpus_read_unlock();		cpus_read_unlock();
	}		}
	EXPORT_SYMBOL_GPL(static_key_slow_inc);		EXPORT_SYMBOL_GPL(static_key_slow_inc);
	@@ -163,10 +166,10 @@ void static_key_disable(struct static_key *key)
	}		}
	EXPORT_SYMBOL_GPL(static_key_disable);		EXPORT_SYMBOL_GPL(static_key_disable);

	static void __static_key_slow_dec(struct static_key *key,		static void static_key_slow_dec_cpuslocked(struct static_key *key,
	unsigned long rate_limit, struct delayed_work *work)		unsigned long rate_limit,
			struct delayed_work *work)
	{		{
	cpus_read_lock();
	/*		/*
	* The negative count check is valid even when a negative		* The negative count check is valid even when a negative
	* key->enabled is in use by static_key_slow_inc(); a		* key->enabled is in use by static_key_slow_inc(); a
	@@ -177,7 +180,6 @@ static void __static_key_slow_dec(struct static_key *key,
	if (!atomic_dec_and_mutex_lock(&key->enabled, &jump_label_mutex)) {		if (!atomic_dec_and_mutex_lock(&key->enabled, &jump_label_mutex)) {
	WARN(atomic_read(&key->enabled) < 0,		WARN(atomic_read(&key->enabled) < 0,
	"jump label: negative count!\n");		"jump label: negative count!\n");
	cpus_read_unlock();
	return;		return;
	}		}

	@@ -188,6 +190,14 @@ static void __static_key_slow_dec(struct static_key *key,
	jump_label_update(key);		jump_label_update(key);
	}		}
	jump_label_unlock();		jump_label_unlock();
			}

			static void __static_key_slow_dec(struct static_key *key,
			unsigned long rate_limit,
			struct delayed_work *work)
			{
			cpus_read_lock();
			static_key_slow_dec_cpuslocked(key, rate_limit, work);
	cpus_read_unlock();		cpus_read_unlock();
	}		}

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