?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
* sysdeps/unix/sysv/linux/powerpc/lowlevellock.h
[glibc.git] / nptl / sysdeps / unix / sysv / linux / powerpc / lowlevellock.h
blobab795348ee044690e6ef1d41f99ac93eac6aded6
1 /* Copyright (C) 2003, 2004, 2006, 2007 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3 Contributed by Paul Mackerras <paulus@au.ibm.com>, 2003.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, write to the Free
17 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
18 02111-1307 USA. */
19
20 #ifndef _LOWLEVELLOCK_H
21 #define _LOWLEVELLOCK_H 1
22
23 #include <time.h>
24 #include <sys/param.h>
25 #include <bits/pthreadtypes.h>
26 #include <atomic.h>
27
28 #ifndef __NR_futex
29 # define __NR_futex 221
30 #endif
31 #define FUTEX_WAIT 0
32 #define FUTEX_WAKE 1
33 #define FUTEX_REQUEUE 3
34 #define FUTEX_CMP_REQUEUE 4
35 #define FUTEX_WAKE_OP 5
36 #define FUTEX_OP_CLEAR_WAKE_IF_GT_ONE ((4 << 24) | 1)
37 #define FUTEX_LOCK_PI 6
38 #define FUTEX_UNLOCK_PI 7
39 #define FUTEX_TRYLOCK_PI 8
40 #define FUTEX_PRIVATE_FLAG 128
41
42 /* Values for 'private' parameter of locking macros. Yes, the
43 definition seems to be backwards. But it is not. The bit will be
44 reversed before passing to the system call. */
45 #define LLL_PRIVATE 0
46 #define LLL_SHARED FUTEX_PRIVATE_FLAG
47
48 #if !defined NOT_IN_libc || defined IS_IN_rtld
49 /* In libc.so or ld.so all futexes are private. */
50 # ifdef __ASSUME_PRIVATE_FUTEX
51 # define __lll_private_flag(fl, private) \
52 ((fl) | FUTEX_PRIVATE_FLAG)
53 # else
54 # define __lll_private_flag(fl, private) \
55 ((fl) | THREAD_GETMEM (THREAD_SELF, header.private_futex))
56 # endif
57 #else
58 # ifdef __ASSUME_PRIVATE_FUTEX
59 # define __lll_private_flag(fl, private) \
60 (((fl) | FUTEX_PRIVATE_FLAG) ^ (private))
61 # else
62 # define __lll_private_flag(fl, private) \
63 (__builtin_constant_p (private) \
64 ? ((private) == 0 \
65 ? ((fl) | THREAD_GETMEM (THREAD_SELF, header.private_futex)) \
66 : (fl)) \
67 : ((fl) | (((private) ^ FUTEX_PRIVATE_FLAG) \
68 & THREAD_GETMEM (THREAD_SELF, header.private_futex))))
69 # endif
70 #endif
71
72 /* Initializer for compatibility lock. */
73 #define LLL_MUTEX_LOCK_INITIALIZER (0)
74
75 #define lll_futex_wait(futexp, val, private) \
76 lll_futex_timed_wait (futexp, val, NULL, private)
77
78 #define lll_futex_timed_wait(futexp, val, timespec, private) \
79 ({ \
80 INTERNAL_SYSCALL_DECL (__err); \
81 long int __ret; \
82 \
83 __ret = INTERNAL_SYSCALL (futex, __err, 4, (futexp), \
84 __lll_private_flag (FUTEX_WAIT, private), \
85 (val), (timespec)); \
86 INTERNAL_SYSCALL_ERROR_P (__ret, __err) ? -__ret : __ret; \
87 })
88
89 #define lll_futex_wake(futexp, nr, private) \
90 ({ \
91 INTERNAL_SYSCALL_DECL (__err); \
92 long int __ret; \
93 \
94 __ret = INTERNAL_SYSCALL (futex, __err, 4, (futexp), \
95 __lll_private_flag (FUTEX_WAKE, private), \
96 (nr), 0); \
97 INTERNAL_SYSCALL_ERROR_P (__ret, __err) ? -__ret : __ret; \
98 })
99
100 #define lll_robust_mutex_dead(futexv) \
101 do \
102 { \
103 INTERNAL_SYSCALL_DECL (__err); \
104 int *__futexp = &(futexv); \
105 \
106 atomic_or (__futexp, FUTEX_OWNER_DIED); \
107 INTERNAL_SYSCALL (futex, __err, 4, __futexp, FUTEX_WAKE, 1, 0); \
108 } \
109 while (0)
110
111 /* Returns non-zero if error happened, zero if success. */
112 #define lll_futex_requeue(futexp, nr_wake, nr_move, mutex, val) \
113 ({ \
114 INTERNAL_SYSCALL_DECL (__err); \
115 long int __ret; \
116 \
117 __ret = INTERNAL_SYSCALL (futex, __err, 6, \
118 (futexp), FUTEX_CMP_REQUEUE, (nr_wake), \
119 (nr_move), (mutex), (val)); \
120 INTERNAL_SYSCALL_ERROR_P (__ret, __err); \
121 })
122
123 /* Returns non-zero if error happened, zero if success. */
124 #define lll_futex_wake_unlock(futexp, nr_wake, nr_wake2, futexp2, private) \
125 ({ \
126 INTERNAL_SYSCALL_DECL (__err); \
127 long int __ret; \
128 \
129 __ret = INTERNAL_SYSCALL (futex, __err, 6, (futexp), \
130 __lll_private_flag (FUTEX_WAKE_OP, private), \
131 (nr_wake), (nr_wake2), (futexp2), \
132 FUTEX_OP_CLEAR_WAKE_IF_GT_ONE); \
133 INTERNAL_SYSCALL_ERROR_P (__ret, __err); \
134 })
135
136
137 #define lll_private_futex_wait(futexp, val) \
138 lll_futex_timed_wait (futexp, val, NULL, LLL_PRIVATE)
139
140 #define lll_private_futex_timed_wait(futexp, val, timeout) \
141 lll_futex_timed_wait (futexp, val, timeout, LLL_PRIVATE)
142
143 #define lll_private_futex_wake(futexp, val) \
144 lll_futex_wake (futexp, val, LLL_PRIVATE)
145
146 #ifdef UP
147 # define __lll_acq_instr ""
148 # define __lll_rel_instr ""
149 #else
150 # define __lll_acq_instr "isync"
151 # ifdef _ARCH_PWR4
152 /*
153 * Newer powerpc64 processors support the new "light weight" sync (lwsync)
154 * So if the build is using -mcpu=[power4,power5,power5+,970] we can
155 * safely use lwsync.
156 */
157 # define __lll_rel_instr "lwsync"
158 # else
159 /*
160 * Older powerpc32 processors don't support the new "light weight"
161 * sync (lwsync). So the only safe option is to use normal sync
162 * for all powerpc32 applications.
163 */
164 # define __lll_rel_instr "sync"
165 # endif
166 #endif
167
168 /* Set *futex to ID if it is 0, atomically. Returns the old value */
169 #define __lll_robust_trylock(futex, id) \
170 ({ int __val; \
171 __asm __volatile ("1: lwarx %0,0,%2" MUTEX_HINT_ACQ "\n" \
172 " cmpwi 0,%0,0\n" \
173 " bne 2f\n" \
174 " stwcx. %3,0,%2\n" \
175 " bne- 1b\n" \
176 "2: " __lll_acq_instr \
177 : "=&r" (__val), "=m" (*futex) \
178 : "r" (futex), "r" (id), "m" (*futex) \
179 : "cr0", "memory"); \
180 __val; \
181 })
182
183 #define lll_robust_mutex_trylock(lock, id) __lll_robust_trylock (&(lock), id)
184
185 /* Set *futex to 1 if it is 0, atomically. Returns the old value */
186 #define __lll_trylock(futex) __lll_robust_trylock (futex, 1)
187
188 #define lll_mutex_trylock(lock) __lll_trylock (&(lock))
189
190 /* Set *futex to 2 if it is 0, atomically. Returns the old value */
191 #define __lll_cond_trylock(futex) __lll_robust_trylock (futex, 2)
192
193 #define lll_mutex_cond_trylock(lock) __lll_cond_trylock (&(lock))
194
195
196 extern void __lll_lock_wait (int *futex) attribute_hidden;
197 extern int __lll_robust_lock_wait (int *futex) attribute_hidden;
198
199 #define lll_mutex_lock(lock) \
200 (void) ({ \
201 int *__futex = &(lock); \
202 if (__builtin_expect (atomic_compare_and_exchange_val_acq (__futex, 1, 0),\
203 0) != 0) \
204 __lll_lock_wait (__futex); \
205 })
206
207 #define lll_robust_mutex_lock(lock, id) \
208 ({ \
209 int *__futex = &(lock); \
210 int __val = 0; \
211 if (__builtin_expect (atomic_compare_and_exchange_bool_acq (__futex, id, \
212 0), 0)) \
213 __val = __lll_robust_lock_wait (__futex); \
214 __val; \
215 })
216
217 #define lll_mutex_cond_lock(lock) \
218 (void) ({ \
219 int *__futex = &(lock); \
220 if (__builtin_expect (atomic_compare_and_exchange_val_acq (__futex, 2, 0),\
221 0) != 0) \
222 __lll_lock_wait (__futex); \
223 })
224
225 #define lll_robust_mutex_cond_lock(lock, id) \
226 ({ \
227 int *__futex = &(lock); \
228 int __val = 0; \
229 int __id = id | FUTEX_WAITERS; \
230 if (__builtin_expect (atomic_compare_and_exchange_bool_acq (__futex, __id,\
231 0), 0)) \
232 __val = __lll_robust_lock_wait (__futex); \
233 __val; \
234 })
235
236
237 extern int __lll_timedlock_wait
238 (int *futex, const struct timespec *) attribute_hidden;
239 extern int __lll_robust_timedlock_wait
240 (int *futex, const struct timespec *) attribute_hidden;
241
242 #define lll_mutex_timedlock(lock, abstime) \
243 ({ \
244 int *__futex = &(lock); \
245 int __val = 0; \
246 if (__builtin_expect (atomic_compare_and_exchange_val_acq (__futex, 1, 0),\
247 0) != 0) \
248 __val = __lll_timedlock_wait (__futex, abstime); \
249 __val; \
250 })
251
252 #define lll_robust_mutex_timedlock(lock, abstime, id) \
253 ({ \
254 int *__futex = &(lock); \
255 int __val = 0; \
256 if (__builtin_expect (atomic_compare_and_exchange_bool_acq (__futex, id, \
257 0), 0)) \
258 __val = __lll_robust_timedlock_wait (__futex, abstime); \
259 __val; \
260 })
261
262 #define lll_mutex_unlock(lock) \
263 ((void) ({ \
264 int *__futex = &(lock); \
265 int __val = atomic_exchange_rel (__futex, 0); \
266 if (__builtin_expect (__val > 1, 0)) \
267 lll_futex_wake (__futex, 1, LLL_SHARED); \
268 }))
269
270 #define lll_robust_mutex_unlock(lock) \
271 ((void) ({ \
272 int *__futex = &(lock); \
273 int __val = atomic_exchange_rel (__futex, 0); \
274 if (__builtin_expect (__val & FUTEX_WAITERS, 0)) \
275 lll_futex_wake (__futex, 1, LLL_SHARED); \
276 }))
277
278 #define lll_mutex_unlock_force(lock) \
279 ((void) ({ \
280 int *__futex = &(lock); \
281 *__futex = 0; \
282 __asm __volatile (__lll_rel_instr ::: "memory"); \
283 lll_futex_wake (__futex, 1, LLL_SHARED); \
284 }))
285
286 #define lll_mutex_islocked(futex) \
287 (futex != 0)
288
289
290 /* Our internal lock implementation is identical to the binary-compatible
291 mutex implementation. */
292
293 /* Type for lock object. */
294 typedef int lll_lock_t;
295
296 /* Initializers for lock. */
297 #define LLL_LOCK_INITIALIZER (0)
298 #define LLL_LOCK_INITIALIZER_LOCKED (1)
299
300 /* The states of a lock are:
301 0 - untaken
302 1 - taken by one user
303 >1 - taken by more users */
304
305 #define lll_trylock(lock) lll_mutex_trylock (lock)
306 #define lll_lock(lock) lll_mutex_lock (lock)
307 #define lll_unlock(lock) lll_mutex_unlock (lock)
308 #define lll_islocked(lock) lll_mutex_islocked (lock)
309
310 /* The kernel notifies a process which uses CLONE_CLEARTID via futex
311 wakeup when the clone terminates. The memory location contains the
312 thread ID while the clone is running and is reset to zero
313 afterwards. */
314 #define lll_wait_tid(tid) \
315 do { \
316 __typeof (tid) __tid; \
317 while ((__tid = (tid)) != 0) \
318 lll_futex_wait (&(tid), __tid, LLL_SHARED); \
319 } while (0)
320
321 extern int __lll_timedwait_tid (int *, const struct timespec *)
322 attribute_hidden;
323
324 #define lll_timedwait_tid(tid, abstime) \
325 ({ \
326 int __res = 0; \
327 if ((tid) != 0) \
328 __res = __lll_timedwait_tid (&(tid), (abstime)); \
329 __res; \
330 })
331
332
333 /* Conditional variable handling. */
334
335 extern void __lll_cond_wait (pthread_cond_t *cond)
336 attribute_hidden;
337 extern int __lll_cond_timedwait (pthread_cond_t *cond,
338 const struct timespec *abstime)
339 attribute_hidden;
340 extern void __lll_cond_wake (pthread_cond_t *cond)
341 attribute_hidden;
342 extern void __lll_cond_broadcast (pthread_cond_t *cond)
343 attribute_hidden;
344
345 #define lll_cond_wait(cond) \
346 __lll_cond_wait (cond)
347 #define lll_cond_timedwait(cond, abstime) \
348 __lll_cond_timedwait (cond, abstime)
349 #define lll_cond_wake(cond) \
350 __lll_cond_wake (cond)
351 #define lll_cond_broadcast(cond) \
352 __lll_cond_broadcast (cond)
353
354 #endif /* lowlevellock.h */
sources.redhat.com git mirror of glibc CVS