2 * Copyright (c) 2010 Isilon Systems, Inc.
3 * Copyright (c) 2010 iX Systems, Inc.
4 * Copyright (c) 2010 Panasas, Inc.
5 * Copyright (c) 2013-2017 Mellanox Technologies, Ltd.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice unmodified, this list of conditions, and the following
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31 #ifndef _LINUX_MUTEX_H_
32 #define _LINUX_MUTEX_H_
34 #include <sys/param.h>
39 #include <linux/spinlock.h>
41 typedef struct mutex {
46 * By defining CONFIG_NO_MUTEX_SKIP LinuxKPI mutexes and asserts will
47 * not be skipped during panic().
49 #ifdef CONFIG_NO_MUTEX_SKIP
50 #define MUTEX_SKIP(void) 0
52 #define MUTEX_SKIP(void) unlikely(SCHEDULER_STOPPED() || kdb_active)
55 #define mutex_lock(_m) do { \
58 sx_xlock(&(_m)->sx); \
61 #define mutex_lock_nested(_m, _s) mutex_lock(_m)
62 #define mutex_lock_nest_lock(_m, _s) mutex_lock(_m)
64 #define mutex_lock_interruptible(_m) ({ \
66 linux_mutex_lock_interruptible(_m); \
69 #define mutex_unlock(_m) do { \
72 sx_xunlock(&(_m)->sx); \
75 #define mutex_trylock(_m) ({ \
77 !!sx_try_xlock(&(_m)->sx); \
80 enum mutex_trylock_recursive_enum {
81 MUTEX_TRYLOCK_FAILED = 0,
82 MUTEX_TRYLOCK_SUCCESS = 1,
83 MUTEX_TRYLOCK_RECURSIVE = 2,
86 static inline __must_check enum mutex_trylock_recursive_enum
87 mutex_trylock_recursive(struct mutex *lock)
89 if (unlikely(sx_xholder(&lock->sx) == curthread))
90 return (MUTEX_TRYLOCK_RECURSIVE);
92 return (mutex_trylock(lock));
95 #define mutex_init(_m) \
96 linux_mutex_init(_m, mutex_name(#_m), SX_NOWITNESS)
98 #define mutex_init_witness(_m) \
99 linux_mutex_init(_m, mutex_name(#_m), SX_DUPOK)
101 #define mutex_destroy(_m) \
102 linux_mutex_destroy(_m)
105 mutex_is_locked(mutex_t *m)
107 return ((struct thread *)SX_OWNER(m->sx.sx_lock) != NULL);
111 mutex_is_owned(mutex_t *m)
113 return (sx_xlocked(&m->sx));
117 /* NOTE: the maximum WITNESS name is 64 chars */
118 #define __mutex_name(name, file, line) \
119 (((const char *){file ":" #line "-" name}) + \
120 (sizeof(file) > 16 ? sizeof(file) - 16 : 0))
122 #define __mutex_name(name, file, line) name
124 #define _mutex_name(...) __mutex_name(__VA_ARGS__)
125 #define mutex_name(name) _mutex_name(name, __FILE__, __LINE__)
127 #define DEFINE_MUTEX(lock) \
129 SX_SYSINIT_FLAGS(lock, &(lock).sx, mutex_name(#lock), SX_DUPOK)
132 linux_mutex_init(mutex_t *m, const char *name, int flags)
134 memset(m, 0, sizeof(*m));
135 sx_init_flags(&m->sx, name, flags);
139 linux_mutex_destroy(mutex_t *m)
141 if (mutex_is_owned(m))
146 extern int linux_mutex_lock_interruptible(mutex_t *m);
148 #endif /* _LINUX_MUTEX_H_ */