Commit 046a619d authored by Jason Low's avatar Jason Low Committed by Ingo Molnar
Browse files

locking/spinlocks/mcs: Rename optimistic_spin_queue() to optimistic_spin_node() 



Currently, the per-cpu nodes structure for the cancellable MCS spinlock is
named "optimistic_spin_queue". However, in a follow up patch in the series
we will be introducing a new structure that serves as the new "handle" for
the lock. It would make more sense if that structure is named
"optimistic_spin_queue". Additionally, since the current use of the
"optimistic_spin_queue" structure are  "nodes", it might be better if we
rename them to "node" anyway.

This preparatory patch renames all current "optimistic_spin_queue"
to "optimistic_spin_node".

Signed-off-by: default avatarJason Low <jason.low2@hp.com>
Signed-off-by: default avatarPeter Zijlstra <peterz@infradead.org>
Cc: Scott Norton <scott.norton@hp.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Waiman Long <waiman.long@hp.com>
Cc: Davidlohr Bueso <davidlohr@hp.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Aswin Chandramouleeswaran <aswin@hp.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Chris Mason <clm@fb.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Josef Bacik <jbacik@fusionio.com>
Link: http://lkml.kernel.org/r/1405358872-3732-2-git-send-email-jason.low2@hp.com


Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent 37e95624

include/linux/mutex.h

+2 −2
Original line number Diff line number Diff line
@@ -46,7 +46,7 @@ 
 * - detects multi-task circular deadlocks and prints out all affected

 *   locks and tasks (and only those tasks)

 */

struct optimistic_spin_queue;

struct optimistic_spin_node;

struct mutex {

	/* 1: unlocked, 0: locked, negative: locked, possible waiters */

	atomic_t		count;
@@ -56,7 +56,7 @@ struct mutex { 
	struct task_struct	*owner;

#endif

#ifdef CONFIG_MUTEX_SPIN_ON_OWNER

	struct optimistic_spin_queue	*osq;	/* Spinner MCS lock */

	struct optimistic_spin_node	*osq;	/* Spinner MCS lock */

#endif

#ifdef CONFIG_DEBUG_MUTEXES

	const char 		*name;

include/linux/rwsem.h

+2 −2
Original line number Diff line number Diff line
@@ -16,7 +16,7 @@ 


#include <linux/atomic.h>



struct optimistic_spin_queue;

struct optimistic_spin_node;

struct rw_semaphore;



#ifdef CONFIG_RWSEM_GENERIC_SPINLOCK
@@ -33,7 +33,7 @@ struct rw_semaphore { 
	 * if the owner is running on the cpu.

	 */

	struct task_struct *owner;

	struct optimistic_spin_queue *osq; /* spinner MCS lock */

	struct optimistic_spin_node *osq; /* spinner MCS lock */

#endif

#ifdef CONFIG_DEBUG_LOCK_ALLOC

	struct lockdep_map	dep_map;

kernel/locking/mcs_spinlock.c

+12 −12
Original line number Diff line number Diff line
@@ -14,18 +14,18 @@ 
 * called from interrupt context and we have preemption disabled while

 * spinning.

 */

static DEFINE_PER_CPU_SHARED_ALIGNED(struct optimistic_spin_queue, osq_node);

static DEFINE_PER_CPU_SHARED_ALIGNED(struct optimistic_spin_node, osq_node);



/*

 * Get a stable @node->next pointer, either for unlock() or unqueue() purposes.

 * Can return NULL in case we were the last queued and we updated @lock instead.

 */

static inline struct optimistic_spin_queue *

osq_wait_next(struct optimistic_spin_queue **lock,

	      struct optimistic_spin_queue *node,

	      struct optimistic_spin_queue *prev)

static inline struct optimistic_spin_node *

osq_wait_next(struct optimistic_spin_node **lock,

	      struct optimistic_spin_node *node,

	      struct optimistic_spin_node *prev)

{

	struct optimistic_spin_queue *next = NULL;

	struct optimistic_spin_node *next = NULL;



	for (;;) {

		if (*lock == node && cmpxchg(lock, node, prev) == node) {
@@ -59,10 +59,10 @@ osq_wait_next(struct optimistic_spin_queue **lock, 
	return next;

}



bool osq_lock(struct optimistic_spin_queue **lock)

bool osq_lock(struct optimistic_spin_node **lock)

{

	struct optimistic_spin_queue *node = this_cpu_ptr(&osq_node);

	struct optimistic_spin_queue *prev, *next;

	struct optimistic_spin_node *node = this_cpu_ptr(&osq_node);

	struct optimistic_spin_node *prev, *next;



	node->locked = 0;

	node->next = NULL;
@@ -149,10 +149,10 @@ unqueue: 
	return false;

}



void osq_unlock(struct optimistic_spin_queue **lock)

void osq_unlock(struct optimistic_spin_node **lock)

{

	struct optimistic_spin_queue *node = this_cpu_ptr(&osq_node);

	struct optimistic_spin_queue *next;

	struct optimistic_spin_node *node = this_cpu_ptr(&osq_node);

	struct optimistic_spin_node *next;



	/*

	 * Fast path for the uncontended case.

kernel/locking/mcs_spinlock.h

+4 −4
Original line number Diff line number Diff line
@@ -118,12 +118,12 @@ void mcs_spin_unlock(struct mcs_spinlock **lock, struct mcs_spinlock *node) 
 * mutex_lock()/rwsem_down_{read,write}() etc.

 */



struct optimistic_spin_queue {

	struct optimistic_spin_queue *next, *prev;

struct optimistic_spin_node {

	struct optimistic_spin_node *next, *prev;

	int locked; /* 1 if lock acquired */

};



extern bool osq_lock(struct optimistic_spin_queue **lock);

extern void osq_unlock(struct optimistic_spin_queue **lock);

extern bool osq_lock(struct optimistic_spin_node **lock);

extern void osq_unlock(struct optimistic_spin_node **lock);



#endif /* __LINUX_MCS_SPINLOCK_H */

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