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
|
/*
* Copyright (c) 2004 François Revol <revol@free.fr>
*
* This 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 of the License, or (at your option) any later version.
*
* This 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 this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
//#define DEBUG
#include "avcodec.h"
#include "common.h"
#include <OS.h>
typedef struct ThreadContext{
AVCodecContext *avctx;
thread_id thread;
sem_id work_sem;
sem_id done_sem;
int (*func)(AVCodecContext *c, void *arg);
void *arg;
int ret;
}ThreadContext;
// it's odd Be never patented that :D
struct benaphore {
vint32 atom;
sem_id sem;
};
static inline int lock_ben(struct benaphore *ben)
{
if (atomic_add(&ben->atom, 1) > 0)
return acquire_sem(ben->sem);
return B_OK;
}
static inline int unlock_ben(struct benaphore *ben)
{
if (atomic_add(&ben->atom, -1) > 1)
return release_sem(ben->sem);
return B_OK;
}
static struct benaphore av_thread_lib_ben;
static int32 ff_thread_func(void *v){
ThreadContext *c= v;
for(;;){
//printf("thread_func %X enter wait\n", (int)v); fflush(stdout);
acquire_sem(c->work_sem);
//printf("thread_func %X after wait (func=%X)\n", (int)v, (int)c->func); fflush(stdout);
if(c->func)
c->ret= c->func(c->avctx, c->arg);
else
return 0;
//printf("thread_func %X signal complete\n", (int)v); fflush(stdout);
release_sem(c->done_sem);
}
return B_OK;
}
/**
* free what has been allocated by avcodec_thread_init().
* must be called after decoding has finished, especially dont call while avcodec_thread_execute() is running
*/
void avcodec_thread_free(AVCodecContext *s){
ThreadContext *c= s->thread_opaque;
int i;
int32 ret;
for(i=0; i<s->thread_count; i++){
c[i].func= NULL;
release_sem(c[i].work_sem);
wait_for_thread(c[i].thread, &ret);
if(c[i].work_sem > B_OK) delete_sem(c[i].work_sem);
if(c[i].done_sem > B_OK) delete_sem(c[i].done_sem);
}
av_freep(&s->thread_opaque);
}
int avcodec_thread_execute(AVCodecContext *s, int (*func)(AVCodecContext *c2, void *arg2),void **arg, int *ret, int count){
ThreadContext *c= s->thread_opaque;
int i;
assert(s == c->avctx);
assert(count <= s->thread_count);
/* note, we can be certain that this is not called with the same AVCodecContext by different threads at the same time */
for(i=0; i<count; i++){
c[i].arg= arg[i];
c[i].func= func;
c[i].ret= 12345;
release_sem(c[i].work_sem);
}
for(i=0; i<count; i++){
acquire_sem(c[i].done_sem);
c[i].func= NULL;
if(ret) ret[i]= c[i].ret;
}
return 0;
}
int avcodec_thread_init(AVCodecContext *s, int thread_count){
int i;
ThreadContext *c;
s->thread_count= thread_count;
assert(!s->thread_opaque);
c= av_mallocz(sizeof(ThreadContext)*thread_count);
s->thread_opaque= c;
for(i=0; i<thread_count; i++){
//printf("init semaphors %d\n", i); fflush(stdout);
c[i].avctx= s;
if((c[i].work_sem = create_sem(0, "ff work sem")) < B_OK)
goto fail;
if((c[i].done_sem = create_sem(0, "ff done sem")) < B_OK)
goto fail;
//printf("create thread %d\n", i); fflush(stdout);
c[i].thread = spawn_thread(ff_thread_func, "libavcodec thread", B_LOW_PRIORITY, &c[i] );
if( c[i].thread < B_OK ) goto fail;
resume_thread(c[i].thread );
}
//printf("init done\n"); fflush(stdout);
s->execute= avcodec_thread_execute;
return 0;
fail:
avcodec_thread_free(s);
return -1;
}
/* provide a mean to serialize calls to avcodec_*() for thread safety. */
int avcodec_thread_lock_lib(void)
{
return lock_ben(&av_thread_lib_ben);
}
int avcodec_thread_unlock_lib(void)
{
return unlock_ben(&av_thread_lib_ben);
}
/* our versions of _init and _fini (which are called by those actually from crt.o) */
void initialize_after(void)
{
av_thread_lib_ben.atom = 0;
av_thread_lib_ben.sem = create_sem(0, "libavcodec benaphore");
}
void uninitialize_before(void)
{
delete_sem(av_thread_lib_ben.sem);
}
|
