/* * 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 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; }