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Diffstat (limited to 'contrib/ffmpeg/libavcodec/pthread.c')
-rw-r--r-- | contrib/ffmpeg/libavcodec/pthread.c | 170 |
1 files changed, 170 insertions, 0 deletions
diff --git a/contrib/ffmpeg/libavcodec/pthread.c b/contrib/ffmpeg/libavcodec/pthread.c new file mode 100644 index 000000000..f2c636bbe --- /dev/null +++ b/contrib/ffmpeg/libavcodec/pthread.c @@ -0,0 +1,170 @@ +/* + * Copyright (c) 2004 Roman Shaposhnik. + * + * 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. + * + * FFmpeg 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, + * 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 + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + * + */ +#include <pthread.h> + +#include "avcodec.h" +#include "common.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; + + pthread_cond_t last_job_cond; + pthread_cond_t current_job_cond; + pthread_mutex_t current_job_lock; + int current_job; + int done; +} ThreadContext; + +static void* worker(void *v) +{ + 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++; + } +} + +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); +} + +int avcodec_thread_execute(AVCodecContext *avctx, action_t* func, void **arg, int *ret, int job_count) +{ + 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); + + avcodec_thread_park_workers(c, avctx->thread_count); + + return 0; +} + +int avcodec_thread_init(AVCodecContext *avctx, int thread_count) +{ + 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; +} |