2 * Copyright (c) 2002, Jeffrey Roberson <jeff@freebsd.org>
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice unmodified, this list of conditions, and the following
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33 #include <sys/_types.h>
34 #include <sys/limits.h>
40 #define UMTX_UNOWNED 0x0
41 #define UMTX_CONTESTED LONG_MIN
44 volatile u_long u_owner; /* Owner of the mutex. */
47 #define USYNC_PROCESS_SHARED 0x0001 /* Process shared sync objs */
49 #define UMUTEX_UNOWNED 0x0
50 #define UMUTEX_CONTESTED 0x80000000U
52 #define UMUTEX_ERROR_CHECK 0x0002 /* Error-checking mutex */
53 #define UMUTEX_PRIO_INHERIT 0x0004 /* Priority inherited mutex */
54 #define UMUTEX_PRIO_PROTECT 0x0008 /* Priority protect mutex */
57 volatile __lwpid_t m_owner; /* Owner of the mutex */
58 uint32_t m_flags; /* Flags of the mutex */
59 uint32_t m_ceilings[2]; /* Priority protect ceiling */
64 volatile uint32_t c_has_waiters; /* Has waiters in kernel */
65 uint32_t c_flags; /* Flags of the condition variable */
66 uint32_t c_spare[2]; /* Spare space */
70 volatile int32_t rw_state;
72 uint32_t rw_blocked_readers;
73 uint32_t rw_blocked_writers;
78 #define URWLOCK_PREFER_READER 0x0002
80 #define URWLOCK_WRITE_OWNER 0x80000000U
81 #define URWLOCK_WRITE_WAITERS 0x40000000U
82 #define URWLOCK_READ_WAITERS 0x20000000U
83 #define URWLOCK_MAX_READERS 0x1fffffffU
84 #define URWLOCK_READER_COUNT(c) ((c) & URWLOCK_MAX_READERS)
86 /* op code for _umtx_op */
87 #define UMTX_OP_LOCK 0
88 #define UMTX_OP_UNLOCK 1
89 #define UMTX_OP_WAIT 2
90 #define UMTX_OP_WAKE 3
91 #define UMTX_OP_MUTEX_TRYLOCK 4
92 #define UMTX_OP_MUTEX_LOCK 5
93 #define UMTX_OP_MUTEX_UNLOCK 6
94 #define UMTX_OP_SET_CEILING 7
95 #define UMTX_OP_CV_WAIT 8
96 #define UMTX_OP_CV_SIGNAL 9
97 #define UMTX_OP_CV_BROADCAST 10
98 #define UMTX_OP_WAIT_UINT 11
99 #define UMTX_OP_RW_RDLOCK 12
100 #define UMTX_OP_RW_WRLOCK 13
101 #define UMTX_OP_RW_UNLOCK 14
102 #define UMTX_OP_WAIT_UINT_PRIVATE 15
103 #define UMTX_OP_WAKE_PRIVATE 16
104 #define UMTX_OP_MUTEX_WAIT 17
105 #define UMTX_OP_MUTEX_WAKE 18
106 #define UMTX_OP_MUTEX_WAKE2 22
107 #define UMTX_OP_MAX 23
109 /* flags for UMTX_OP_CV_WAIT */
110 #define UMTX_CHECK_UNPARKING 0x01
114 int _umtx_op(void *obj, int op, u_long val, void *uaddr, void *uaddr2);
117 * Old (deprecated) userland mutex system calls.
119 int _umtx_lock(struct umtx *mtx);
120 int _umtx_unlock(struct umtx *mtx);
123 * Standard api. Try uncontested acquire/release and asks the
124 * kernel to resolve failures.
127 umtx_init(struct umtx *umtx)
129 umtx->u_owner = UMTX_UNOWNED;
132 static __inline u_long
133 umtx_owner(struct umtx *umtx)
135 return (umtx->u_owner & ~LONG_MIN);
139 umtx_lock(struct umtx *umtx, u_long id)
141 if (atomic_cmpset_acq_long(&umtx->u_owner, UMTX_UNOWNED, id) == 0)
142 if (_umtx_lock(umtx) == -1)
148 umtx_trylock(struct umtx *umtx, u_long id)
150 if (atomic_cmpset_acq_long(&umtx->u_owner, UMTX_UNOWNED, id) == 0)
156 umtx_timedlock(struct umtx *umtx, u_long id, const struct timespec *timeout)
158 if (atomic_cmpset_acq_long(&umtx->u_owner, UMTX_UNOWNED, id) == 0)
159 if (_umtx_op(umtx, UMTX_OP_LOCK, id, 0,
160 __DECONST(void *, timeout)) == -1)
166 umtx_unlock(struct umtx *umtx, u_long id)
168 if (atomic_cmpset_rel_long(&umtx->u_owner, id, UMTX_UNOWNED) == 0)
169 if (_umtx_unlock(umtx) == -1)
175 umtx_wait(u_long *p, long val, const struct timespec *timeout)
177 if (_umtx_op(p, UMTX_OP_WAIT, val, 0,
178 __DECONST(void *, timeout)) == -1)
183 /* Wake threads waiting on a user address. */
185 umtx_wake(u_long *p, int nr_wakeup)
187 if (_umtx_op(p, UMTX_OP_WAKE, nr_wakeup, 0, 0) == -1)
195 * The umtx_key structure is used by both the Linux futex code and the
196 * umtx implementation to map userland addresses to unique keys.
210 /* Key to represent a unique userland synchronous object */
217 struct vm_object *object;
231 #define THREAD_SHARE 0
232 #define PROCESS_SHARE 1
238 umtx_key_match(const struct umtx_key *k1, const struct umtx_key *k2)
240 return (k1->type == k2->type &&
241 k1->info.both.a == k2->info.both.a &&
242 k1->info.both.b == k2->info.both.b);
245 int umtx_copyin_timeout(const void *, struct timespec *);
246 int umtx_key_get(void *, int, int, struct umtx_key *);
247 void umtx_key_release(struct umtx_key *);
248 struct umtx_q *umtxq_alloc(void);
249 void umtxq_free(struct umtx_q *);
250 int kern_umtx_wake(struct thread *, void *, int, int);
251 void umtx_pi_adjust(struct thread *, u_char);
252 void umtx_thread_init(struct thread *);
253 void umtx_thread_fini(struct thread *);
254 void umtx_thread_alloc(struct thread *);
255 void umtx_thread_exit(struct thread *);
256 #endif /* !_KERNEL */
257 #endif /* !_SYS_UMTX_H_ */