1 /* Copyright (C) 2003, 2004 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, write to the Free
16 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
19 #ifndef _LOWLEVELLOCK_H
20 #define _LOWLEVELLOCK_H 1
23 #include <sys/param.h>
24 #include <bits/pthreadtypes.h>
31 /* Initializer for compatibility lock. */
32 #define LLL_MUTEX_LOCK_INITIALIZER (0)
33 #define LLL_MUTEX_LOCK_INITIALIZER_LOCKED (1)
34 #define LLL_MUTEX_LOCK_INITIALIZER_WAITERS (2)
36 extern int __lll_mutex_lock_wait (int val, int *__futex) attribute_hidden;
37 extern int __lll_mutex_timedlock_wait (int val, int *__futex,
38 const struct timespec *abstime)
40 extern int __lll_mutex_unlock_wake (int *__futex) attribute_hidden;
43 #define lll_mutex_trylock(futex) \
44 ({ unsigned char __result; \
60 "r" (LLL_MUTEX_LOCK_INITIALIZER_LOCKED), \
61 "r" (LLL_MUTEX_LOCK_INITIALIZER) \
62 : "r0", "r1", "r2", "t", "memory"); \
65 #define lll_mutex_cond_trylock(futex) \
66 ({ unsigned char __result; \
82 "r" (LLL_MUTEX_LOCK_INITIALIZER_WAITERS), \
83 "r" (LLL_MUTEX_LOCK_INITIALIZER) \
84 : "r0", "r1", "r2", "t", "memory"); \
87 #define lll_mutex_lock(futex) \
88 (void) ({ int __result, val, *__futex = &(futex); \
99 : "=&r" (__result) : "r" (1), "r" (__futex) \
100 : "r0", "r1", "t", "memory"); \
102 __lll_mutex_lock_wait (__result, __futex); })
104 /* Special version of lll_mutex_lock which causes the unlock function to
105 always wakeup waiters. */
106 #define lll_mutex_cond_lock(futex) \
107 (void) ({ int __result, val, *__futex = &(futex); \
118 : "=&r" (__result) : "r" (2), "r" (__futex) \
119 : "r0", "r1", "t", "memory"); \
121 __lll_mutex_lock_wait (__result, __futex); })
123 #define lll_mutex_timedlock(futex, timeout) \
124 ({ int __result, val, *__futex = &(futex); \
135 : "=&r" (__result) : "r" (1), "r" (__futex) \
136 : "r0", "r1", "t", "memory"); \
138 __result = __lll_mutex_timedlock_wait (__result, __futex, timeout); \
141 #define lll_mutex_unlock(futex) \
142 (void) ({ int __result, *__futex = &(futex); \
152 : "=&r" (__result) : "r" (__futex) \
153 : "r0", "r1", "memory"); \
155 __lll_mutex_unlock_wake (__futex); })
157 #define lll_mutex_islocked(futex) \
161 /* We have a separate internal lock implementation which is not tied
162 to binary compatibility. */
164 /* Type for lock object. */
165 typedef int lll_lock_t;
167 /* Initializers for lock. */
168 #define LLL_LOCK_INITIALIZER (0)
169 #define LLL_LOCK_INITIALIZER_LOCKED (1)
172 # ifdef NEED_SYSCALL_INST_PAD
173 # define SYSCALL_WITH_INST_PAD "\
174 trapa #0x14; or r0,r0; or r0,r0; or r0,r0; or r0,r0; or r0,r0"
176 # define SYSCALL_WITH_INST_PAD "\
180 #define lll_futex_wait(futex, val) \
183 register unsigned long __r3 asm ("r3") = SYS_futex; \
184 register unsigned long __r4 asm ("r4") = (unsigned long) (futex); \
185 register unsigned long __r5 asm ("r5") = FUTEX_WAIT; \
186 register unsigned long __r6 asm ("r6") = (unsigned long) (val); \
187 register unsigned long __r7 asm ("r7") = 0; \
188 __asm __volatile (SYSCALL_WITH_INST_PAD \
190 : "r" (__r3), "r" (__r4), "r" (__r5), \
191 "r" (__r6), "r" (__r7) \
196 #define lll_futex_wake(futex, nr) \
199 register unsigned long __r3 asm ("r3") = SYS_futex; \
200 register unsigned long __r4 asm ("r4") = (unsigned long) (futex); \
201 register unsigned long __r5 asm ("r5") = FUTEX_WAKE; \
202 register unsigned long __r6 asm ("r6") = (unsigned long) (nr); \
203 register unsigned long __r7 asm ("r7") = 0; \
204 __asm __volatile (SYSCALL_WITH_INST_PAD \
206 : "r" (__r3), "r" (__r4), "r" (__r5), \
207 "r" (__r6), "r" (__r7) \
212 extern int lll_unlock_wake_cb (int *__futex) attribute_hidden;
215 /* The states of a lock are:
217 1 - taken by one user
218 2 - taken by more users */
220 #define lll_trylock(futex) lll_mutex_trylock (futex)
221 #define lll_lock(futex) lll_mutex_lock (futex)
222 #define lll_unlock(futex) lll_mutex_unlock (futex)
224 #define lll_islocked(futex) \
225 (futex != LLL_LOCK_INITIALIZER)
228 /* The kernel notifies a process with uses CLONE_CLEARTID via futex
229 wakeup when the clone terminates. The memory location contains the
230 thread ID while the clone is running and is reset to zero
233 extern int __lll_wait_tid (int *tid) attribute_hidden;
234 #define lll_wait_tid(tid) \
236 __typeof (tid) *__tid = &(tid); \
237 while (*__tid != 0) \
238 lll_futex_wait (__tid, *__tid); \
241 extern int __lll_timedwait_tid (int *tid, const struct timespec *abstime)
243 #define lll_timedwait_tid(tid, abstime) \
248 if (abstime->tv_nsec < 0 || abstime->tv_nsec >= 1000000000) \
251 __result = __lll_timedwait_tid (&tid, abstime); \
256 /* Conditional variable handling. */
258 extern void __lll_cond_wait (pthread_cond_t *cond) attribute_hidden;
259 extern int __lll_cond_timedwait (pthread_cond_t *cond,
260 const struct timespec *abstime)
262 extern void __lll_cond_wake (pthread_cond_t *cond) attribute_hidden;
263 extern void __lll_cond_broadcast (pthread_cond_t *cond) attribute_hidden;
266 #define lll_cond_wait(cond) \
267 __lll_cond_wait (cond)
268 #define lll_cond_timedwait(cond, abstime) \
269 __lll_cond_timedwait (cond, abstime)
270 #define lll_cond_wake(cond) \
271 __lll_cond_wake (cond)
272 #define lll_cond_broadcast(cond) \
273 __lll_cond_broadcast (cond)
275 #endif /* lowlevellock.h */