Commit 9c80172b authored by Sebastian Andrzej Siewior's avatar Sebastian Andrzej Siewior Committed by Rafael J. Wysocki
Browse files

kernel/SRCU: provide a static initializer 



There are macros for static initializer for the three out of four
possible notifier types, that are:
	ATOMIC_NOTIFIER_HEAD()
	BLOCKING_NOTIFIER_HEAD()
	RAW_NOTIFIER_HEAD()

This patch provides a static initilizer for the forth type to make it
complete.

Signed-off-by: default avatarSebastian Andrzej Siewior <bigeasy@linutronix.de>
Tested-by: default avatarPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: default avatarPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent c7d1f119

include/linux/notifier.h

+29 −5
Original line number Diff line number Diff line
@@ -43,9 +43,7 @@ 
 * in srcu_notifier_call_chain(): no cache bounces and no memory barriers.

 * As compensation, srcu_notifier_chain_unregister() is rather expensive.

 * SRCU notifier chains should be used when the chain will be called very

 * often but notifier_blocks will seldom be removed.  Also, SRCU notifier

 * chains are slightly more difficult to use because they require special

 * runtime initialization.

 * often but notifier_blocks will seldom be removed.

 */



struct notifier_block;
@@ -91,7 +89,7 @@ struct srcu_notifier_head { 
		(name)->head = NULL;		\

	} while (0)



/* srcu_notifier_heads must be initialized and cleaned up dynamically */

/* srcu_notifier_heads must be cleaned up dynamically */

extern void srcu_init_notifier_head(struct srcu_notifier_head *nh);

#define srcu_cleanup_notifier_head(name)	\

		cleanup_srcu_struct(&(name)->srcu);
@@ -104,7 +102,13 @@ extern void srcu_init_notifier_head(struct srcu_notifier_head *nh); 
		.head = NULL }

#define RAW_NOTIFIER_INIT(name)	{				\

		.head = NULL }

/* srcu_notifier_heads cannot be initialized statically */



#define SRCU_NOTIFIER_INIT(name, pcpu)				\

	{							\

		.mutex = __MUTEX_INITIALIZER(name.mutex),	\

		.head = NULL,					\

		.srcu = __SRCU_STRUCT_INIT(name.srcu, pcpu),	\

	}



#define ATOMIC_NOTIFIER_HEAD(name)				\

	struct atomic_notifier_head name =			\
@@ -116,6 +120,26 @@ extern void srcu_init_notifier_head(struct srcu_notifier_head *nh); 
	struct raw_notifier_head name =				\

		RAW_NOTIFIER_INIT(name)



#ifdef CONFIG_TREE_SRCU

#define _SRCU_NOTIFIER_HEAD(name, mod)				\

	static DEFINE_PER_CPU(struct srcu_data,			\

			name##_head_srcu_data);			\

	mod struct srcu_notifier_head name =			\

			SRCU_NOTIFIER_INIT(name, name##_head_srcu_data)



#else

#define _SRCU_NOTIFIER_HEAD(name, mod)				\

	mod struct srcu_notifier_head name =			\

			SRCU_NOTIFIER_INIT(name, name)



#endif



#define SRCU_NOTIFIER_HEAD(name)				\

	_SRCU_NOTIFIER_HEAD(name, /* not static */)



#define SRCU_NOTIFIER_HEAD_STATIC(name)				\

	_SRCU_NOTIFIER_HEAD(name, static)



#ifdef __KERNEL__



extern int atomic_notifier_chain_register(struct atomic_notifier_head *nh,

include/linux/srcutiny.h

+3 −3
Original line number Diff line number Diff line
@@ -43,7 +43,7 @@ struct srcu_struct { 


void srcu_drive_gp(struct work_struct *wp);



#define __SRCU_STRUCT_INIT(name)					\

#define __SRCU_STRUCT_INIT(name, __ignored)				\

{									\

	.srcu_wq = __SWAIT_QUEUE_HEAD_INITIALIZER(name.srcu_wq),	\

	.srcu_cb_tail = &name.srcu_cb_head,				\
@@ -56,9 +56,9 @@ void srcu_drive_gp(struct work_struct *wp); 
 * Tree SRCU, which needs some per-CPU data.

 */

#define DEFINE_SRCU(name) \

	struct srcu_struct name = __SRCU_STRUCT_INIT(name)

	struct srcu_struct name = __SRCU_STRUCT_INIT(name, name)

#define DEFINE_STATIC_SRCU(name) \

	static struct srcu_struct name = __SRCU_STRUCT_INIT(name)

	static struct srcu_struct name = __SRCU_STRUCT_INIT(name, name)



void synchronize_srcu(struct srcu_struct *sp);

include/linux/srcutree.h

+3 −3
Original line number Diff line number Diff line
@@ -104,9 +104,9 @@ struct srcu_struct { 
#define SRCU_STATE_SCAN1	1

#define SRCU_STATE_SCAN2	2



#define __SRCU_STRUCT_INIT(name)					\

#define __SRCU_STRUCT_INIT(name, pcpu_name)				\

	{								\

		.sda = &name##_srcu_data,				\

		.sda = &pcpu_name,					\

		.lock = __SPIN_LOCK_UNLOCKED(name.lock),		\

		.srcu_gp_seq_needed = 0 - 1,				\

		__SRCU_DEP_MAP_INIT(name)				\
@@ -133,7 +133,7 @@ struct srcu_struct { 
 */

#define __DEFINE_SRCU(name, is_static)					\

	static DEFINE_PER_CPU(struct srcu_data, name##_srcu_data);\

	is_static struct srcu_struct name = __SRCU_STRUCT_INIT(name)

	is_static struct srcu_struct name = __SRCU_STRUCT_INIT(name, name##_srcu_data)

#define DEFINE_SRCU(name)		__DEFINE_SRCU(name, /* not static */)

#define DEFINE_STATIC_SRCU(name)	__DEFINE_SRCU(name, static)

CRA Git | Maintained and supported by SUSTech CRA and CCSE