/*
- * Copyright (c) 2004 Michael Niedermayer <michaelni@gmx.at>
+ * Copyright (c) 2004 Roman Shaposhnik
+ * Copyright (c) 2008 Alexander Strange (astrange@ithinksw.com)
*
- * This library is free software; you can redistribute it and/or
+ * Many thanks to Steven M. Schultz for providing clever ideas and
+ * to Michael Niedermayer <michaelni@gmx.at> for writing initial
+ * implementation.
+ *
+ * This file is part of Libav.
+ *
+ * Libav 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.
+ * version 2.1 of the License, or (at your option) any later version.
*
- * This library is distributed in the hope that it will be useful,
+ * Libav 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
- *
+ * License along with Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
-#include <semaphore.h>
-#include <pthread.h>
-//#define DEBUG
+/**
+ * @file
+ * Multithreading support functions
+ * @see doc/multithreading.txt
+ */
#include "avcodec.h"
-#include "common.h"
-
-
-typedef struct ThreadContext{
- AVCodecContext *avctx;
- pthread_t thread;
- sem_t work_sem;
- sem_t done_sem;
- int (*func)(AVCodecContext *c, void *arg);
- void *arg;
- int ret;
-}ThreadContext;
-
-static void * thread_func(void *v){
- ThreadContext *c= v;
-
- for(;;){
-//printf("thread_func %X enter wait\n", (int)v); fflush(stdout);
- sem_wait(&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 NULL;
-//printf("thread_func %X signal complete\n", (int)v); fflush(stdout);
- sem_post(&c->done_sem);
- }
-
- return NULL;
-}
+#include "internal.h"
+#include "pthread_internal.h"
+#include "thread.h"
/**
- * free what has been allocated by avcodec_pthread_init().
- * must be called after decoding has finished, especially dont call while avcodec_pthread_execute() is running
+ * Set the threading algorithms used.
+ *
+ * Threading requires more than one thread.
+ * Frame threading requires entire frames to be passed to the codec,
+ * and introduces extra decoding delay, so is incompatible with low_delay.
+ *
+ * @param avctx The context.
*/
-void avcodec_pthread_free(AVCodecContext *s){
- ThreadContext *c= s->thread_opaque;
- int i;
-
- for(i=0; i<s->thread_count; i++){
- int val;
-
- sem_getvalue(&c[i].work_sem, &val); assert(val == 0);
- sem_getvalue(&c[i].done_sem, &val); assert(val == 0);
-
- c[i].func= NULL;
- sem_post(&c[i].work_sem);
- pthread_join(c[i].thread, NULL);
- sem_destroy(&c[i].work_sem);
- sem_destroy(&c[i].done_sem);
+static void validate_thread_parameters(AVCodecContext *avctx)
+{
+ int frame_threading_supported = (avctx->codec->capabilities & AV_CODEC_CAP_FRAME_THREADS)
+ && !(avctx->flags & AV_CODEC_FLAG_TRUNCATED)
+ && !(avctx->flags & AV_CODEC_FLAG_LOW_DELAY)
+ && !(avctx->flags2 & AV_CODEC_FLAG2_CHUNKS);
+ if (avctx->thread_count == 1) {
+ avctx->active_thread_type = 0;
+ } else if (frame_threading_supported && (avctx->thread_type & FF_THREAD_FRAME)) {
+ avctx->active_thread_type = FF_THREAD_FRAME;
+ } else if (avctx->codec->capabilities & AV_CODEC_CAP_SLICE_THREADS &&
+ avctx->thread_type & FF_THREAD_SLICE) {
+ avctx->active_thread_type = FF_THREAD_SLICE;
+ } else if (!(avctx->codec->capabilities & AV_CODEC_CAP_AUTO_THREADS)) {
+ avctx->thread_count = 1;
+ avctx->active_thread_type = 0;
}
- av_freep(&s->thread_opaque);
+ if (avctx->thread_count > MAX_AUTO_THREADS)
+ av_log(avctx, AV_LOG_WARNING,
+ "Application has requested %d threads. Using a thread count greater than %d is not recommended.\n",
+ avctx->thread_count, MAX_AUTO_THREADS);
}
-int avcodec_pthread_execute(AVCodecContext *s, int (*func)(AVCodecContext *c2, void *arg2),void **arg, int *ret, int count){
- ThreadContext *c= s->thread_opaque;
- int i, val;
-
- 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 */
+int ff_thread_init(AVCodecContext *avctx)
+{
+ validate_thread_parameters(avctx);
- for(i=0; i<count; i++){
- sem_getvalue(&c[i].work_sem, &val); assert(val == 0);
- sem_getvalue(&c[i].done_sem, &val); assert(val == 0);
-
- c[i].arg= arg[i];
- c[i].func= func;
- c[i].ret= 12345;
- sem_post(&c[i].work_sem);
- }
- for(i=0; i<count; i++){
- sem_wait(&c[i].done_sem);
+ if (avctx->active_thread_type&FF_THREAD_SLICE)
+ return ff_slice_thread_init(avctx);
+ else if (avctx->active_thread_type&FF_THREAD_FRAME)
+ return ff_frame_thread_init(avctx);
- sem_getvalue(&c[i].work_sem, &val); assert(val == 0);
- sem_getvalue(&c[i].done_sem, &val); assert(val == 0);
-
- c[i].func= NULL;
- if(ret) ret[i]= c[i].ret;
- }
return 0;
}
-int avcodec_pthread_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(sem_init(&c[i].work_sem, 0, 0))
- goto fail;
- if(sem_init(&c[i].done_sem, 0, 0))
- goto fail;
-//printf("create thread %d\n", i); fflush(stdout);
- if(pthread_create(&c[i].thread, NULL, thread_func, &c[i]))
- goto fail;
- }
-//printf("init done\n"); fflush(stdout);
-
- s->execute= avcodec_pthread_execute;
-
- return 0;
-fail:
- avcodec_pthread_free(s);
- return -1;
+void ff_thread_free(AVCodecContext *avctx)
+{
+ if (avctx->active_thread_type&FF_THREAD_FRAME)
+ ff_frame_thread_free(avctx, avctx->thread_count);
+ else
+ ff_slice_thread_free(avctx);
}