Commit ad282a81 authored by Jakub Kicinski's avatar Jakub Kicinski Committed by Ingo Molnar
Browse files

locking/static_key: Add support for deferred static branches 



Add deferred static branches.  We can't unfortunately use the
nice trick of encapsulating the entire structure in true/false
variants, because the inside has to be either struct static_key_true
or struct static_key_false.  Use defines to pass the appropriate
members to the helpers separately.

Signed-off-by: default avatarJakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: default avatarSimon Horman <simon.horman@netronome.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: alexei.starovoitov@gmail.com
Cc: ard.biesheuvel@linaro.org
Cc: oss-drivers@netronome.com
Cc: yamada.masahiro@socionext.com
Link: https://lkml.kernel.org/r/20190330000854.30142-2-jakub.kicinski@netronome.com


Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent 948f8376

include/linux/jump_label_ratelimit.h

+61 −3
Original line number Diff line number Diff line
@@ -12,21 +12,79 @@ struct static_key_deferred { 
	struct delayed_work work;

};



extern void static_key_slow_dec_deferred(struct static_key_deferred *key);

extern void static_key_deferred_flush(struct static_key_deferred *key);

struct static_key_true_deferred {

	struct static_key_true key;

	unsigned long timeout;

	struct delayed_work work;

};



struct static_key_false_deferred {

	struct static_key_false key;

	unsigned long timeout;

	struct delayed_work work;

};



#define static_key_slow_dec_deferred(x)					\

	__static_key_slow_dec_deferred(&(x)->key, &(x)->work, (x)->timeout)

#define static_branch_slow_dec_deferred(x)				\

	__static_key_slow_dec_deferred(&(x)->key.key, &(x)->work, (x)->timeout)



#define static_key_deferred_flush(x)					\

	__static_key_deferred_flush((x), &(x)->work)



extern void

__static_key_slow_dec_deferred(struct static_key *key,

			       struct delayed_work *work,

			       unsigned long timeout);

extern void __static_key_deferred_flush(void *key, struct delayed_work *work);

extern void

jump_label_rate_limit(struct static_key_deferred *key, unsigned long rl);



extern void jump_label_update_timeout(struct work_struct *work);



#define DEFINE_STATIC_KEY_DEFERRED_TRUE(name, rl)			\

	struct static_key_true_deferred name = {			\

		.key =		{ STATIC_KEY_INIT_TRUE },		\

		.timeout =	(rl),					\

		.work =	__DELAYED_WORK_INITIALIZER((name).work,		\

						   jump_label_update_timeout, \

						   0),			\

	}



#define DEFINE_STATIC_KEY_DEFERRED_FALSE(name, rl)			\

	struct static_key_false_deferred name = {			\

		.key =		{ STATIC_KEY_INIT_FALSE },		\

		.timeout =	(rl),					\

		.work =	__DELAYED_WORK_INITIALIZER((name).work,		\

						   jump_label_update_timeout, \

						   0),			\

	}



#define static_branch_deferred_inc(x)	static_branch_inc(&(x)->key)



#else	/* !CONFIG_JUMP_LABEL */

struct static_key_deferred {

	struct static_key  key;

};

struct static_key_true_deferred {

	struct static_key_true key;

};

struct static_key_false_deferred {

	struct static_key_false key;

};

#define DEFINE_STATIC_KEY_DEFERRED_TRUE(name, rl)	\

	struct static_key_true_deferred name = { STATIC_KEY_TRUE_INIT }

#define DEFINE_STATIC_KEY_DEFERRED_FALSE(name, rl)	\

	struct static_key_false_deferred name = { STATIC_KEY_FALSE_INIT }



#define static_branch_slow_dec_deferred(x)	static_branch_dec(&(x)->key)



static inline void static_key_slow_dec_deferred(struct static_key_deferred *key)

{

	STATIC_KEY_CHECK_USE(key);

	static_key_slow_dec(&key->key);

}

static inline void static_key_deferred_flush(struct static_key_deferred *key)

static inline void static_key_deferred_flush(void *key)

{

	STATIC_KEY_CHECK_USE(key);

}

kernel/jump_label.c

+10 −7
Original line number Diff line number Diff line
@@ -244,12 +244,13 @@ static void __static_key_slow_dec(struct static_key *key, 
	cpus_read_unlock();

}



static void jump_label_update_timeout(struct work_struct *work)

void jump_label_update_timeout(struct work_struct *work)

{

	struct static_key_deferred *key =

		container_of(work, struct static_key_deferred, work.work);

	__static_key_slow_dec(&key->key, 0, NULL);

}

EXPORT_SYMBOL_GPL(jump_label_update_timeout);



void static_key_slow_dec(struct static_key *key)

{
@@ -264,19 +265,21 @@ void static_key_slow_dec_cpuslocked(struct static_key *key) 
	__static_key_slow_dec_cpuslocked(key, 0, NULL);

}



void static_key_slow_dec_deferred(struct static_key_deferred *key)

void __static_key_slow_dec_deferred(struct static_key *key,

				    struct delayed_work *work,

				    unsigned long timeout)

{

	STATIC_KEY_CHECK_USE(key);

	__static_key_slow_dec(&key->key, key->timeout, &key->work);

	__static_key_slow_dec(key, timeout, work);

}

EXPORT_SYMBOL_GPL(static_key_slow_dec_deferred);

EXPORT_SYMBOL_GPL(__static_key_slow_dec_deferred);



void static_key_deferred_flush(struct static_key_deferred *key)

void __static_key_deferred_flush(void *key, struct delayed_work *work)

{

	STATIC_KEY_CHECK_USE(key);

	flush_delayed_work(&key->work);

	flush_delayed_work(work);

}

EXPORT_SYMBOL_GPL(static_key_deferred_flush);

EXPORT_SYMBOL_GPL(__static_key_deferred_flush);



void jump_label_rate_limit(struct static_key_deferred *key,

		unsigned long rl)

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