2 * Copyright (c) 2004 François Revol <revol@free.fr>
4 * This file is part of FFmpeg.
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
26 typedef struct ThreadContext{
27 AVCodecContext *avctx;
31 int (*func)(AVCodecContext *c, void *arg);
36 // it's odd Be never patented that :D
41 static inline int lock_ben(struct benaphore *ben)
43 if (atomic_add(&ben->atom, 1) > 0)
44 return acquire_sem(ben->sem);
47 static inline int unlock_ben(struct benaphore *ben)
49 if (atomic_add(&ben->atom, -1) > 1)
50 return release_sem(ben->sem);
54 static struct benaphore av_thread_lib_ben;
56 static int32 ff_thread_func(void *v){
60 //printf("thread_func %X enter wait\n", (int)v); fflush(stdout);
61 acquire_sem(c->work_sem);
62 //printf("thread_func %X after wait (func=%X)\n", (int)v, (int)c->func); fflush(stdout);
64 c->ret= c->func(c->avctx, c->arg);
67 //printf("thread_func %X signal complete\n", (int)v); fflush(stdout);
68 release_sem(c->done_sem);
75 * Free what has been allocated by avcodec_thread_init().
76 * Must be called after decoding has finished, especially do not call while avcodec_thread_execute() is running.
78 void avcodec_thread_free(AVCodecContext *s){
79 ThreadContext *c= s->thread_opaque;
83 for(i=0; i<s->thread_count; i++){
86 release_sem(c[i].work_sem);
87 wait_for_thread(c[i].thread, &ret);
88 if(c[i].work_sem > B_OK) delete_sem(c[i].work_sem);
89 if(c[i].done_sem > B_OK) delete_sem(c[i].done_sem);
92 av_freep(&s->thread_opaque);
95 int avcodec_thread_execute(AVCodecContext *s, int (*func)(AVCodecContext *c2, void *arg2),void *arg, int *ret, int count, int size){
96 ThreadContext *c= s->thread_opaque;
99 assert(s == c->avctx);
100 assert(count <= s->thread_count);
102 /* note, we can be certain that this is not called with the same AVCodecContext by different threads at the same time */
104 for(i=0; i<count; i++){
105 c[i].arg= (char*)arg + i*size;
109 release_sem(c[i].work_sem);
111 for(i=0; i<count; i++){
112 acquire_sem(c[i].done_sem);
115 if(ret) ret[i]= c[i].ret;
120 int avcodec_thread_init(AVCodecContext *s, int thread_count){
124 s->thread_count= thread_count;
126 if (thread_count <= 1)
129 assert(!s->thread_opaque);
130 c= av_mallocz(sizeof(ThreadContext)*thread_count);
133 for(i=0; i<thread_count; i++){
134 //printf("init semaphors %d\n", i); fflush(stdout);
137 if((c[i].work_sem = create_sem(0, "ff work sem")) < B_OK)
139 if((c[i].done_sem = create_sem(0, "ff done sem")) < B_OK)
142 //printf("create thread %d\n", i); fflush(stdout);
143 c[i].thread = spawn_thread(ff_thread_func, "libavcodec thread", B_LOW_PRIORITY, &c[i] );
144 if( c[i].thread < B_OK ) goto fail;
145 resume_thread(c[i].thread );
147 //printf("init done\n"); fflush(stdout);
149 s->execute= avcodec_thread_execute;
153 avcodec_thread_free(s);
157 /* provide a mean to serialize calls to avcodec_*() for thread safety. */
159 int avcodec_thread_lock_lib(void)
161 return lock_ben(&av_thread_lib_ben);
164 int avcodec_thread_unlock_lib(void)
166 return unlock_ben(&av_thread_lib_ben);
169 /* our versions of _init and _fini (which are called by those actually from crt.o) */
171 void initialize_after(void)
173 av_thread_lib_ben.atom = 0;
174 av_thread_lib_ben.sem = create_sem(0, "libavcodec benaphore");
177 void uninitialize_before(void)
179 delete_sem(av_thread_lib_ben.sem);