/*
- * Copyright (c) 2004 Roman Shaposhnik.
+ * Copyright (c) 2004 Roman Shaposhnik
+ * Copyright (c) 2008 Alexander Strange (astrange@ithinksw.com)
*
* 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 FFmpeg.
+ * This file is part of Libav.
*
- * FFmpeg is free software; you can redistribute it and/or
+ * 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 2.1 of the License, or (at your option) any later version.
*
- * FFmpeg 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 FFmpeg; if not, write to the Free Software
+ * License along with Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- *
*/
-#include <pthread.h>
-
-#include "avcodec.h"
-typedef int (action_t)(AVCodecContext *c, void *arg);
-
-typedef struct ThreadContext {
- pthread_t *workers;
- action_t *func;
- void **args;
- int *rets;
- int rets_count;
- int job_count;
+/**
+ * @file
+ * Multithreading support functions
+ * @see doc/multithreading.txt
+ */
- pthread_cond_t last_job_cond;
- pthread_cond_t current_job_cond;
- pthread_mutex_t current_job_lock;
- int current_job;
- int done;
-} ThreadContext;
+#include "avcodec.h"
+#include "internal.h"
+#include "pthread_internal.h"
+#include "thread.h"
-static void* worker(void *v)
+/**
+ * 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.
+ */
+static void validate_thread_parameters(AVCodecContext *avctx)
{
- AVCodecContext *avctx = v;
- ThreadContext *c = avctx->thread_opaque;
- int our_job = c->job_count;
- int thread_count = avctx->thread_count;
- int self_id;
-
- pthread_mutex_lock(&c->current_job_lock);
- self_id = c->current_job++;
- for (;;){
- while (our_job >= c->job_count) {
- if (c->current_job == thread_count + c->job_count)
- pthread_cond_signal(&c->last_job_cond);
-
- pthread_cond_wait(&c->current_job_cond, &c->current_job_lock);
- our_job = self_id;
-
- if (c->done) {
- pthread_mutex_unlock(&c->current_job_lock);
- return NULL;
- }
- }
- pthread_mutex_unlock(&c->current_job_lock);
-
- c->rets[our_job%c->rets_count] = c->func(avctx, c->args[our_job]);
-
- pthread_mutex_lock(&c->current_job_lock);
- our_job = c->current_job++;
+ 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;
}
-}
-
-static av_always_inline void avcodec_thread_park_workers(ThreadContext *c, int thread_count)
-{
- pthread_cond_wait(&c->last_job_cond, &c->current_job_lock);
- pthread_mutex_unlock(&c->current_job_lock);
-}
-
-void avcodec_thread_free(AVCodecContext *avctx)
-{
- ThreadContext *c = avctx->thread_opaque;
- int i;
-
- pthread_mutex_lock(&c->current_job_lock);
- c->done = 1;
- pthread_cond_broadcast(&c->current_job_cond);
- pthread_mutex_unlock(&c->current_job_lock);
-
- for (i=0; i<avctx->thread_count; i++)
- pthread_join(c->workers[i], NULL);
- pthread_mutex_destroy(&c->current_job_lock);
- pthread_cond_destroy(&c->current_job_cond);
- pthread_cond_destroy(&c->last_job_cond);
- av_free(c->workers);
- av_free(c);
+ 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_thread_execute(AVCodecContext *avctx, action_t* func, void **arg, int *ret, int job_count)
+int ff_thread_init(AVCodecContext *avctx)
{
- ThreadContext *c= avctx->thread_opaque;
- int dummy_ret;
-
- if (job_count <= 0)
- return 0;
-
- pthread_mutex_lock(&c->current_job_lock);
-
- c->current_job = avctx->thread_count;
- c->job_count = job_count;
- c->args = arg;
- c->func = func;
- if (ret) {
- c->rets = ret;
- c->rets_count = job_count;
- } else {
- c->rets = &dummy_ret;
- c->rets_count = 1;
- }
- pthread_cond_broadcast(&c->current_job_cond);
+ validate_thread_parameters(avctx);
- avcodec_thread_park_workers(c, avctx->thread_count);
+ 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);
return 0;
}
-int avcodec_thread_init(AVCodecContext *avctx, int thread_count)
+void ff_thread_free(AVCodecContext *avctx)
{
- int i;
- ThreadContext *c;
-
- c = av_mallocz(sizeof(ThreadContext));
- if (!c)
- return -1;
-
- c->workers = av_mallocz(sizeof(pthread_t)*thread_count);
- if (!c->workers) {
- av_free(c);
- return -1;
- }
-
- avctx->thread_opaque = c;
- avctx->thread_count = thread_count;
- c->current_job = 0;
- c->job_count = 0;
- c->done = 0;
- pthread_cond_init(&c->current_job_cond, NULL);
- pthread_cond_init(&c->last_job_cond, NULL);
- pthread_mutex_init(&c->current_job_lock, NULL);
- pthread_mutex_lock(&c->current_job_lock);
- for (i=0; i<thread_count; i++) {
- if(pthread_create(&c->workers[i], NULL, worker, avctx)) {
- avctx->thread_count = i;
- pthread_mutex_unlock(&c->current_job_lock);
- avcodec_thread_free(avctx);
- return -1;
- }
- }
-
- avcodec_thread_park_workers(c, thread_count);
-
- avctx->execute = avcodec_thread_execute;
- return 0;
+ if (avctx->active_thread_type&FF_THREAD_FRAME)
+ ff_frame_thread_free(avctx, avctx->thread_count);
+ else
+ ff_slice_thread_free(avctx);
}