Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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kernel
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linux
1#ifndef _LINUX_PERCPU_RWSEM_H
2#define _LINUX_PERCPU_RWSEM_H
3
4#include <linux/atomic.h>
5#include <linux/rwsem.h>
6#include <linux/percpu.h>
7#include <linux/wait.h>
8#include <linux/lockdep.h>
9
10struct percpu_rw_semaphore {
11 unsigned int __percpu *fast_read_ctr;
12 atomic_t write_ctr;
13 struct rw_semaphore rw_sem;
14 atomic_t slow_read_ctr;
15 wait_queue_head_t write_waitq;
16};
17
18extern void percpu_down_read(struct percpu_rw_semaphore *);
19extern int percpu_down_read_trylock(struct percpu_rw_semaphore *);
20extern void percpu_up_read(struct percpu_rw_semaphore *);
21
22extern void percpu_down_write(struct percpu_rw_semaphore *);
23extern void percpu_up_write(struct percpu_rw_semaphore *);
24
25extern int __percpu_init_rwsem(struct percpu_rw_semaphore *,
26 const char *, struct lock_class_key *);
27extern void percpu_free_rwsem(struct percpu_rw_semaphore *);
28
29#define percpu_init_rwsem(brw) \
30({ \
31 static struct lock_class_key rwsem_key; \
32 __percpu_init_rwsem(brw, #brw, &rwsem_key); \
33})
34
35
36#define percpu_rwsem_is_held(sem) lockdep_is_held(&(sem)->rw_sem)
37
38static inline void percpu_rwsem_release(struct percpu_rw_semaphore *sem,
39 bool read, unsigned long ip)
40{
41 lock_release(&sem->rw_sem.dep_map, 1, ip);
42#ifdef CONFIG_RWSEM_SPIN_ON_OWNER
43 if (!read)
44 sem->rw_sem.owner = NULL;
45#endif
46}
47
48static inline void percpu_rwsem_acquire(struct percpu_rw_semaphore *sem,
49 bool read, unsigned long ip)
50{
51 lock_acquire(&sem->rw_sem.dep_map, 0, 1, read, 1, NULL, ip);
52}
53
54#endif