1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
|
/* Copyright (C) 2003 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Martin Schwidefsky <schwidefsky@de.ibm.com>, 2003.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#ifndef _LOWLEVELLOCK_H
#define _LOWLEVELLOCK_H 1
#include <time.h>
#include <sys/param.h>
#include <bits/pthreadtypes.h>
#define SYS_futex 238
#define FUTEX_WAIT 0
#define FUTEX_WAKE 1
#define FUTEX_REQUEUE 3
/* Initializer for compatibility lock. */
#define LLL_MUTEX_LOCK_INITIALIZER (0)
#define lll_futex_wait(futex, val) \
({ \
register unsigned long int __r2 asm ("2") = (unsigned long int) (futex); \
register unsigned long int __r3 asm ("3") = FUTEX_WAIT; \
register unsigned long int __r4 asm ("4") = (unsigned long int) (val); \
register unsigned long int __r5 asm ("5") = 0ul; \
register unsigned long __result asm ("2"); \
\
__asm __volatile ("svc %b1" \
: "=d" (__result) \
: "i" (SYS_futex), "0" (__r2), "d" (__r3), \
"d" (__r4), "d" (__r5) \
: "cc", "memory" ); \
__result; \
})
#define lll_futex_timed_wait(futex, val, timespec) \
({ \
register unsigned long int __r2 asm ("2") = (unsigned long int) (futex); \
register unsigned long int __r3 asm ("3") = FUTEX_WAIT; \
register unsigned long int __r4 asm ("4") = (unsigned long int) (val); \
register unsigned long int __r5 asm ("5") = (unsigned long int)(timespec);\
register unsigned long int __result asm ("2"); \
\
__asm __volatile ("svc %b1" \
: "=d" (__result) \
: "i" (SYS_futex), "0" (__r2), "d" (__r3), \
"d" (__r4), "d" (__r5) \
: "cc", "memory" ); \
__result; \
})
#define lll_futex_wake(futex, nr) \
({ \
register unsigned long int __r2 asm ("2") = (unsigned long int) (futex); \
register unsigned long int __r3 asm ("3") = FUTEX_WAKE; \
register unsigned long int __r4 asm ("4") = (unsigned long int) (nr); \
register unsigned long int __result asm ("2"); \
\
__asm __volatile ("svc %b1" \
: "=d" (__result) \
: "i" (SYS_futex), "0" (__r2), "d" (__r3), "d" (__r4) \
: "cc", "memory" ); \
__result; \
})
#define lll_futex_requeue(futex, nr_wake, nr_move, mutex) \
({ \
register unsigned long int __r2 asm ("2") = (unsigned long int) (futex); \
register unsigned long int __r3 asm ("3") = FUTEX_REQUEUE; \
register unsigned long int __r4 asm ("4") = (long int) (nr_wake); \
register unsigned long int __r5 asm ("5") = (long int) (nr_move); \
register unsigned long int __r6 asm ("6") = (unsigned long int) (mutex); \
register unsigned long __result asm ("2"); \
\
__asm __volatile ("svc %b1" \
: "=d" (__result) \
: "i" (SYS_futex), "0" (__r2), "d" (__r3), \
"d" (__r4), "d" (__r5), "d" (__r6) \
: "cc", "memory" ); \
__result; \
})
#define lll_compare_and_swap(futex, oldval, newval, operation) \
do { \
__typeof (futex) __futex = (futex); \
__asm __volatile (" l %1,%0\n" \
"0: " operation "\n" \
" cs %1,%2,%0\n" \
" jl 0b\n" \
"1:" \
: "=Q" (*__futex), "=&d" (oldval), "=&d" (newval) \
: "m" (*__futex) : "cc" ); \
} while (0)
static inline int
__attribute__ ((always_inline))
__lll_mutex_trylock (int *futex)
{
unsigned int old;
__asm __volatile ("cs %0,%3,%1"
: "=d" (old), "=Q" (*futex)
: "0" (0), "d" (1), "m" (*futex) : "cc" );
return old != 0;
}
#define lll_mutex_trylock(futex) __lll_mutex_trylock (&(futex))
extern void ___lll_mutex_lock (int *, int) attribute_hidden;
static inline void
__attribute__ ((always_inline))
__lll_mutex_lock (int *futex)
{
int oldval;
int newval;
lll_compare_and_swap (futex, oldval, newval, "lr %2,%1; ahi %2,1");
if (oldval > 0)
___lll_mutex_lock (futex, newval);
}
#define lll_mutex_lock(futex) __lll_mutex_lock (&(futex))
static inline void
__attribute__ ((always_inline))
__lll_mutex_cond_lock (int *futex)
{
int oldval;
int newval;
lll_compare_and_swap (futex, oldval, newval, "lr %2,%1; ahi %2,2");
if (oldval > 0)
___lll_mutex_lock (futex, newval);
}
#define lll_mutex_cond_lock(futex) __lll_mutex_cond_lock (&(futex))
extern int ___lll_mutex_timedlock (int *, const struct timespec *, int)
attribute_hidden;
static inline int
__attribute__ ((always_inline))
__lll_mutex_timedlock (int *futex, const struct timespec *abstime)
{
int oldval;
int newval;
int result = 0;
lll_compare_and_swap (futex, oldval, newval, "lr %2,%1; ahi %2,1");
if (oldval > 0)
result = ___lll_mutex_timedlock (futex, abstime, newval);
return result;
}
#define lll_mutex_timedlock(futex, abstime) \
__lll_mutex_timedlock (&(futex), abstime)
static inline void
__attribute__ ((always_inline))
__lll_mutex_unlock (int *futex)
{
int oldval;
int newval = 0;
lll_compare_and_swap (futex, oldval, newval, "slr %2,%2");
if (oldval > 1)
lll_futex_wake (futex, 1);
}
#define lll_mutex_unlock(futex) \
__lll_mutex_unlock(&(futex))
static inline void
__attribute__ ((always_inline))
__lll_mutex_unlock_force (int *futex)
{
*futex = 0;
lll_futex_wake (futex, 1);
}
#define lll_mutex_unlock_force(futex) \
__lll_mutex_unlock_force(&(futex))
#define lll_mutex_islocked(futex) \
(futex != 0)
/* We have a separate internal lock implementation which is not tied
to binary compatibility. */
/* Type for lock object. */
typedef int lll_lock_t;
/* Initializers for lock. */
#define LLL_LOCK_INITIALIZER (1)
#define LLL_LOCK_INITIALIZER_LOCKED (0)
extern int lll_unlock_wake_cb (int *__futex) attribute_hidden;
/* The states of a lock are:
1 - untaken
0 - taken by one user
<0 - taken by more users */
static inline int
__attribute__ ((always_inline))
__lll_trylock (int *futex)
{
unsigned int old;
__asm __volatile ("cs %0,%3,%1"
: "=d" (old), "=Q" (*futex)
: "0" (1), "d" (0), "m" (*futex) : "cc" );
return old != 1;
}
#define lll_trylock(futex) __lll_trylock (&(futex))
extern void ___lll_lock (int *, int) attribute_hidden;
static inline void
__attribute__ ((always_inline))
__lll_lock (int *futex)
{
int oldval;
int newval;
lll_compare_and_swap (futex, oldval, newval, "lr %2,%1; ahi %2,-1");
if (newval < 0)
___lll_lock (futex, newval);
}
#define lll_lock(futex) __lll_lock (&(futex))
static inline void
__attribute__ ((always_inline))
__lll_unlock (int *futex)
{
int oldval;
int newval;
lll_compare_and_swap (futex, oldval, newval, "lhi %2,1");
if (oldval < 0)
lll_futex_wake (futex, 1);
}
#define lll_unlock(futex) __lll_unlock(&(futex))
#define lll_islocked(futex) \
(futex != 1)
/* The kernel notifies a process with uses CLONE_CLEARTID via futex
wakeup when the clone terminates. The memory location contains the
thread ID while the clone is running and is reset to zero
afterwards. */
static inline void
__attribute__ ((always_inline))
__lll_wait_tid (int *ptid)
{
int tid;
while ((tid = *ptid) != 0)
lll_futex_wait (ptid, tid);
}
#define lll_wait_tid(tid) __lll_wait_tid(&(tid))
extern int ___lll_timedwait_tid (int *, const struct timespec *)
attribute_hidden;
static inline int
__attribute__ ((always_inline))
__lll_timedwait_tid (int *ptid, const struct timespec *abstime)
{
if (*ptid == 0)
return 0;
return ___lll_timedwait_tid (ptid, abstime);
}
#define lll_timedwait_tid(tid, abstime) __lll_timedwait_tid (&(tid), abstime)
/* Conditional variable handling. */
extern void __lll_cond_wait (pthread_cond_t *cond)
attribute_hidden;
extern int __lll_cond_timedwait (pthread_cond_t *cond,
const struct timespec *abstime)
attribute_hidden;
extern void __lll_cond_wake (pthread_cond_t *cond)
attribute_hidden;
extern void __lll_cond_broadcast (pthread_cond_t *cond)
attribute_hidden;
#define lll_cond_wait(cond) \
__lll_cond_wait (cond)
#define lll_cond_timedwait(cond, abstime) \
__lll_cond_timedwait (cond, abstime)
#define lll_cond_wake(cond) \
__lll_cond_wake (cond)
#define lll_cond_broadcast(cond) \
__lll_cond_broadcast (cond)
#endif /* lowlevellock.h */
|
