1 #ifndef _LINUX_PERCPU_RWSEM_H
2 #define _LINUX_PERCPU_RWSEM_H
4 #include <linux/atomic.h>
5 #include <linux/rwsem.h>
6 #include <linux/percpu.h>
7 #include <linux/wait.h>
8 #include <linux/rcu_sync.h>
9 #include <linux/lockdep.h>
11 struct percpu_rw_semaphore
{
13 unsigned int __percpu
*fast_read_ctr
;
14 struct rw_semaphore rw_sem
;
15 atomic_t slow_read_ctr
;
16 wait_queue_head_t write_waitq
;
19 extern void percpu_down_read(struct percpu_rw_semaphore
*);
20 extern int percpu_down_read_trylock(struct percpu_rw_semaphore
*);
21 extern void percpu_up_read(struct percpu_rw_semaphore
*);
23 extern void percpu_down_write(struct percpu_rw_semaphore
*);
24 extern void percpu_up_write(struct percpu_rw_semaphore
*);
26 extern int __percpu_init_rwsem(struct percpu_rw_semaphore
*,
27 const char *, struct lock_class_key
*);
28 extern void percpu_free_rwsem(struct percpu_rw_semaphore
*);
30 #define percpu_init_rwsem(brw) \
32 static struct lock_class_key rwsem_key; \
33 __percpu_init_rwsem(brw, #brw, &rwsem_key); \
37 #define percpu_rwsem_is_held(sem) lockdep_is_held(&(sem)->rw_sem)
39 static inline void percpu_rwsem_release(struct percpu_rw_semaphore
*sem
,
40 bool read
, unsigned long ip
)
42 lock_release(&sem
->rw_sem
.dep_map
, 1, ip
);
43 #ifdef CONFIG_RWSEM_SPIN_ON_OWNER
45 sem
->rw_sem
.owner
= NULL
;
49 static inline void percpu_rwsem_acquire(struct percpu_rw_semaphore
*sem
,
50 bool read
, unsigned long ip
)
52 lock_acquire(&sem
->rw_sem
.dep_map
, 0, 1, read
, 1, NULL
, ip
);