2 * This file is part of FFmpeg.
4 * FFmpeg is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2.1 of the License, or (at your option) any later version.
9 * FFmpeg is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with FFmpeg; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 * Slice multithreading support functions
22 * @see doc/multithreading.txt
29 #include "pthread_internal.h"
32 #include "libavutil/avassert.h"
33 #include "libavutil/common.h"
34 #include "libavutil/cpu.h"
35 #include "libavutil/mem.h"
36 #include "libavutil/thread.h"
38 typedef int (action_func)(AVCodecContext *c, void *arg);
39 typedef int (action_func2)(AVCodecContext *c, void *arg, int jobnr, int threadnr);
41 typedef struct SliceThreadContext {
50 pthread_cond_t last_job_cond;
51 pthread_cond_t current_job_cond;
52 pthread_mutex_t current_job_lock;
53 unsigned current_execute;
60 pthread_cond_t *progress_cond;
61 pthread_mutex_t *progress_mutex;
64 static void* attribute_align_arg worker(void *v)
66 AVCodecContext *avctx = v;
67 SliceThreadContext *c = avctx->internal->thread_ctx;
68 unsigned last_execute = 0;
69 int our_job = c->job_count;
70 int thread_count = avctx->thread_count;
73 pthread_mutex_lock(&c->current_job_lock);
74 self_id = c->current_job++;
77 while (our_job >= c->job_count) {
78 if (c->current_job == thread_count + c->job_count)
79 pthread_cond_signal(&c->last_job_cond);
81 while (last_execute == c->current_execute && !c->done)
82 pthread_cond_wait(&c->current_job_cond, &c->current_job_lock);
83 last_execute = c->current_execute;
87 pthread_mutex_unlock(&c->current_job_lock);
91 pthread_mutex_unlock(&c->current_job_lock);
93 ret = c->func ? c->func(avctx, (char*)c->args + our_job*c->job_size):
94 c->func2(avctx, c->args, our_job, self_id);
96 c->rets[our_job%c->job_count] = ret;
98 pthread_mutex_lock(&c->current_job_lock);
99 our_job = c->current_job++;
103 void ff_slice_thread_free(AVCodecContext *avctx)
105 SliceThreadContext *c = avctx->internal->thread_ctx;
108 pthread_mutex_lock(&c->current_job_lock);
110 pthread_cond_broadcast(&c->current_job_cond);
111 for (i = 0; i < c->thread_count; i++)
112 pthread_cond_broadcast(&c->progress_cond[i]);
113 pthread_mutex_unlock(&c->current_job_lock);
115 for (i=0; i<avctx->thread_count; i++)
116 pthread_join(c->workers[i], NULL);
118 for (i = 0; i < c->thread_count; i++) {
119 pthread_mutex_destroy(&c->progress_mutex[i]);
120 pthread_cond_destroy(&c->progress_cond[i]);
123 pthread_mutex_destroy(&c->current_job_lock);
124 pthread_cond_destroy(&c->current_job_cond);
125 pthread_cond_destroy(&c->last_job_cond);
127 av_freep(&c->entries);
128 av_freep(&c->progress_mutex);
129 av_freep(&c->progress_cond);
131 av_freep(&c->workers);
132 av_freep(&avctx->internal->thread_ctx);
135 static av_always_inline void thread_park_workers(SliceThreadContext *c, int thread_count)
137 while (c->current_job != thread_count + c->job_count)
138 pthread_cond_wait(&c->last_job_cond, &c->current_job_lock);
139 pthread_mutex_unlock(&c->current_job_lock);
142 static int thread_execute(AVCodecContext *avctx, action_func* func, void *arg, int *ret, int job_count, int job_size)
144 SliceThreadContext *c = avctx->internal->thread_ctx;
146 if (!(avctx->active_thread_type&FF_THREAD_SLICE) || avctx->thread_count <= 1)
147 return avcodec_default_execute(avctx, func, arg, ret, job_count, job_size);
152 pthread_mutex_lock(&c->current_job_lock);
154 c->current_job = avctx->thread_count;
155 c->job_count = job_count;
156 c->job_size = job_size;
160 c->current_execute++;
161 pthread_cond_broadcast(&c->current_job_cond);
163 thread_park_workers(c, avctx->thread_count);
168 static int thread_execute2(AVCodecContext *avctx, action_func2* func2, void *arg, int *ret, int job_count)
170 SliceThreadContext *c = avctx->internal->thread_ctx;
172 return thread_execute(avctx, NULL, arg, ret, job_count, 0);
175 int ff_slice_thread_init(AVCodecContext *avctx)
178 SliceThreadContext *c;
179 int thread_count = avctx->thread_count;
185 // We cannot do this in the encoder init as the threads are created before
186 if (av_codec_is_encoder(avctx->codec) &&
187 avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO &&
188 avctx->height > 2800)
189 thread_count = avctx->thread_count = 1;
192 int nb_cpus = av_cpu_count();
194 nb_cpus = FFMIN(nb_cpus, (avctx->height+15)/16);
195 // use number of cores + 1 as thread count if there is more than one
197 thread_count = avctx->thread_count = FFMIN(nb_cpus + 1, MAX_AUTO_THREADS);
199 thread_count = avctx->thread_count = 1;
202 if (thread_count <= 1) {
203 avctx->active_thread_type = 0;
207 c = av_mallocz(sizeof(SliceThreadContext));
211 c->workers = av_mallocz_array(thread_count, sizeof(pthread_t));
217 avctx->internal->thread_ctx = c;
222 pthread_cond_init(&c->current_job_cond, NULL);
223 pthread_cond_init(&c->last_job_cond, NULL);
224 pthread_mutex_init(&c->current_job_lock, NULL);
225 pthread_mutex_lock(&c->current_job_lock);
226 for (i=0; i<thread_count; i++) {
227 if(pthread_create(&c->workers[i], NULL, worker, avctx)) {
228 avctx->thread_count = i;
229 pthread_mutex_unlock(&c->current_job_lock);
230 ff_thread_free(avctx);
235 thread_park_workers(c, thread_count);
237 avctx->execute = thread_execute;
238 avctx->execute2 = thread_execute2;
242 void ff_thread_report_progress2(AVCodecContext *avctx, int field, int thread, int n)
244 SliceThreadContext *p = avctx->internal->thread_ctx;
245 int *entries = p->entries;
247 pthread_mutex_lock(&p->progress_mutex[thread]);
249 pthread_cond_signal(&p->progress_cond[thread]);
250 pthread_mutex_unlock(&p->progress_mutex[thread]);
253 void ff_thread_await_progress2(AVCodecContext *avctx, int field, int thread, int shift)
255 SliceThreadContext *p = avctx->internal->thread_ctx;
256 int *entries = p->entries;
258 if (!entries || !field) return;
260 thread = thread ? thread - 1 : p->thread_count - 1;
262 pthread_mutex_lock(&p->progress_mutex[thread]);
263 while ((entries[field - 1] - entries[field]) < shift){
264 pthread_cond_wait(&p->progress_cond[thread], &p->progress_mutex[thread]);
266 pthread_mutex_unlock(&p->progress_mutex[thread]);
269 int ff_alloc_entries(AVCodecContext *avctx, int count)
273 if (avctx->active_thread_type & FF_THREAD_SLICE) {
274 SliceThreadContext *p = avctx->internal->thread_ctx;
277 av_assert0(p->thread_count == avctx->thread_count);
278 av_freep(&p->entries);
281 p->thread_count = avctx->thread_count;
282 p->entries = av_mallocz_array(count, sizeof(int));
284 if (!p->progress_mutex) {
285 p->progress_mutex = av_malloc_array(p->thread_count, sizeof(pthread_mutex_t));
286 p->progress_cond = av_malloc_array(p->thread_count, sizeof(pthread_cond_t));
289 if (!p->entries || !p->progress_mutex || !p->progress_cond) {
290 av_freep(&p->entries);
291 av_freep(&p->progress_mutex);
292 av_freep(&p->progress_cond);
293 return AVERROR(ENOMEM);
295 p->entries_count = count;
297 for (i = 0; i < p->thread_count; i++) {
298 pthread_mutex_init(&p->progress_mutex[i], NULL);
299 pthread_cond_init(&p->progress_cond[i], NULL);
306 void ff_reset_entries(AVCodecContext *avctx)
308 SliceThreadContext *p = avctx->internal->thread_ctx;
309 memset(p->entries, 0, p->entries_count * sizeof(int));