Libav
pthread_frame.c
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1 /*
2  * This file is part of Libav.
3  *
4  * Libav 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.
8  *
9  * Libav 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.
13  *
14  * You should have received a copy of the GNU Lesser General Public
15  * License along with Libav; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17  */
18 
25 #include "config.h"
26 
27 #include <stdint.h>
28 
29 #if HAVE_PTHREADS
30 #include <pthread.h>
31 #elif HAVE_W32THREADS
32 #include "compat/w32pthreads.h"
33 #endif
34 
35 #include "avcodec.h"
36 #include "internal.h"
37 #include "pthread_internal.h"
38 #include "thread.h"
39 
40 #include "libavutil/avassert.h"
41 #include "libavutil/buffer.h"
42 #include "libavutil/common.h"
43 #include "libavutil/cpu.h"
44 #include "libavutil/frame.h"
45 #include "libavutil/log.h"
46 #include "libavutil/mem.h"
47 
51 typedef struct PerThreadContext {
53 
59 
62 
64 
68 
70  int got_frame;
71  int result;
72 
73  enum {
81  } state;
82 
90 
94 
98 typedef struct FrameThreadContext {
101 
103 
106 
107  int delaying;
112  int die;
114 
123 {
124  PerThreadContext *p = arg;
125  FrameThreadContext *fctx = p->parent;
126  AVCodecContext *avctx = p->avctx;
127  const AVCodec *codec = avctx->codec;
128 
129  while (1) {
130  if (p->state == STATE_INPUT_READY && !fctx->die) {
132  while (p->state == STATE_INPUT_READY && !fctx->die)
135  }
136 
137  if (fctx->die) break;
138 
139  if (!codec->update_thread_context && avctx->thread_safe_callbacks)
140  ff_thread_finish_setup(avctx);
141 
143  av_frame_unref(p->frame);
144  p->got_frame = 0;
145  p->result = codec->decode(avctx, p->frame, &p->got_frame, &p->avpkt);
146 
147  if ((p->result < 0 || !p->got_frame) && p->frame->buf[0]) {
148  if (avctx->internal->allocate_progress)
149  av_log(avctx, AV_LOG_ERROR, "A frame threaded decoder did not "
150  "free the frame on failure. This is a bug, please report it.\n");
151  av_frame_unref(p->frame);
152  }
153 
154  if (p->state == STATE_SETTING_UP) ff_thread_finish_setup(avctx);
155 
156  p->state = STATE_INPUT_READY;
157 
161 
163  }
164 
165  return NULL;
166 }
167 
175 static int update_context_from_thread(AVCodecContext *dst, AVCodecContext *src, int for_user)
176 {
177  int err = 0;
178 
179  if (dst != src) {
180  dst->time_base = src->time_base;
181  dst->width = src->width;
182  dst->height = src->height;
183  dst->pix_fmt = src->pix_fmt;
184 
185  dst->coded_width = src->coded_width;
186  dst->coded_height = src->coded_height;
187 
188  dst->has_b_frames = src->has_b_frames;
189  dst->idct_algo = src->idct_algo;
190 
194 
195  dst->profile = src->profile;
196  dst->level = src->level;
197 
199  dst->ticks_per_frame = src->ticks_per_frame;
200  dst->color_primaries = src->color_primaries;
201 
202  dst->color_trc = src->color_trc;
203  dst->colorspace = src->colorspace;
204  dst->color_range = src->color_range;
206 
207  dst->hwaccel = src->hwaccel;
208  dst->hwaccel_context = src->hwaccel_context;
209  }
210 
211  if (for_user) {
212  dst->coded_frame = src->coded_frame;
213  } else {
214  if (dst->codec->update_thread_context)
215  err = dst->codec->update_thread_context(dst, src);
216  }
217 
218  return err;
219 }
220 
229 {
230 #define copy_fields(s, e) memcpy(&dst->s, &src->s, (char*)&dst->e - (char*)&dst->s);
231  dst->flags = src->flags;
232 
233  dst->draw_horiz_band= src->draw_horiz_band;
234  dst->get_buffer2 = src->get_buffer2;
235 #if FF_API_GET_BUFFER
237  dst->get_buffer = src->get_buffer;
238  dst->release_buffer = src->release_buffer;
240 #endif
241 
242  dst->opaque = src->opaque;
243  dst->debug = src->debug;
244 
245  dst->slice_flags = src->slice_flags;
246  dst->flags2 = src->flags2;
247 
248  copy_fields(skip_loop_filter, subtitle_header);
249 
250  dst->frame_number = src->frame_number;
252 
253  if (src->slice_count && src->slice_offset) {
254  if (dst->slice_count < src->slice_count) {
255  int *tmp = av_realloc(dst->slice_offset, src->slice_count *
256  sizeof(*dst->slice_offset));
257  if (!tmp) {
258  av_free(dst->slice_offset);
259  return AVERROR(ENOMEM);
260  }
261  dst->slice_offset = tmp;
262  }
263  memcpy(dst->slice_offset, src->slice_offset,
264  src->slice_count * sizeof(*dst->slice_offset));
265  }
266  dst->slice_count = src->slice_count;
267  return 0;
268 #undef copy_fields
269 }
270 
273 {
274  FrameThreadContext *fctx = p->parent;
275 
276  while (p->num_released_buffers > 0) {
277  AVFrame *f;
278 
280 
281  // fix extended data in case the caller screwed it up
284  f->extended_data = f->data;
285  av_frame_unref(f);
286 
288  }
289 }
290 
292 {
293  FrameThreadContext *fctx = p->parent;
294  PerThreadContext *prev_thread = fctx->prev_thread;
295  const AVCodec *codec = p->avctx->codec;
296 
297  if (!avpkt->size && !(codec->capabilities & CODEC_CAP_DELAY)) return 0;
298 
300 
302 
303  if (prev_thread) {
304  int err;
305  if (prev_thread->state == STATE_SETTING_UP) {
306  pthread_mutex_lock(&prev_thread->progress_mutex);
307  while (prev_thread->state == STATE_SETTING_UP)
308  pthread_cond_wait(&prev_thread->progress_cond, &prev_thread->progress_mutex);
309  pthread_mutex_unlock(&prev_thread->progress_mutex);
310  }
311 
312  err = update_context_from_thread(p->avctx, prev_thread->avctx, 0);
313  if (err) {
315  return err;
316  }
317  }
318 
320  p->avpkt = *avpkt;
321  if (avpkt->buf)
322  p->avpkt.buf = av_buffer_ref(avpkt->buf);
323  else {
325  p->avpkt.data = p->buf;
326  memcpy(p->buf, avpkt->data, avpkt->size);
327  memset(p->buf + avpkt->size, 0, FF_INPUT_BUFFER_PADDING_SIZE);
328  }
329 
330  p->state = STATE_SETTING_UP;
333 
334  /*
335  * If the client doesn't have a thread-safe get_buffer(),
336  * then decoding threads call back to the main thread,
337  * and it calls back to the client here.
338  */
339 
341  if (!p->avctx->thread_safe_callbacks && (
343  p->avctx->get_buffer ||
344 #endif
347  while (p->state != STATE_SETUP_FINISHED && p->state != STATE_INPUT_READY) {
349  while (p->state == STATE_SETTING_UP)
351 
352  if (p->state == STATE_GET_BUFFER) {
354  p->state = STATE_SETTING_UP;
356  }
358  }
359  }
360 
361  fctx->prev_thread = p;
362  fctx->next_decoding++;
363 
364  return 0;
365 }
366 
368  AVFrame *picture, int *got_picture_ptr,
369  AVPacket *avpkt)
370 {
371  FrameThreadContext *fctx = avctx->internal->thread_ctx;
372  int finished = fctx->next_finished;
373  PerThreadContext *p;
374  int err;
375 
376  /*
377  * Submit a packet to the next decoding thread.
378  */
379 
380  p = &fctx->threads[fctx->next_decoding];
381  err = update_context_from_user(p->avctx, avctx);
382  if (err) return err;
383  err = submit_packet(p, avpkt);
384  if (err) return err;
385 
386  /*
387  * If we're still receiving the initial packets, don't return a frame.
388  */
389 
390  if (fctx->delaying) {
391  if (fctx->next_decoding >= (avctx->thread_count-1)) fctx->delaying = 0;
392 
393  *got_picture_ptr=0;
394  if (avpkt->size)
395  return avpkt->size;
396  }
397 
398  /*
399  * Return the next available frame from the oldest thread.
400  * If we're at the end of the stream, then we have to skip threads that
401  * didn't output a frame, because we don't want to accidentally signal
402  * EOF (avpkt->size == 0 && *got_picture_ptr == 0).
403  */
404 
405  do {
406  p = &fctx->threads[finished++];
407 
408  if (p->state != STATE_INPUT_READY) {
410  while (p->state != STATE_INPUT_READY)
413  }
414 
415  av_frame_move_ref(picture, p->frame);
416  *got_picture_ptr = p->got_frame;
417  picture->pkt_dts = p->avpkt.dts;
418 
419  /*
420  * A later call with avkpt->size == 0 may loop over all threads,
421  * including this one, searching for a frame to return before being
422  * stopped by the "finished != fctx->next_finished" condition.
423  * Make sure we don't mistakenly return the same frame again.
424  */
425  p->got_frame = 0;
426 
427  if (finished >= avctx->thread_count) finished = 0;
428  } while (!avpkt->size && !*got_picture_ptr && finished != fctx->next_finished);
429 
430  update_context_from_thread(avctx, p->avctx, 1);
431 
432  if (fctx->next_decoding >= avctx->thread_count) fctx->next_decoding = 0;
433 
434  fctx->next_finished = finished;
435 
436  /* return the size of the consumed packet if no error occurred */
437  return (p->result >= 0) ? avpkt->size : p->result;
438 }
439 
440 void ff_thread_report_progress(ThreadFrame *f, int n, int field)
441 {
442  PerThreadContext *p;
443  int *progress = f->progress ? (int*)f->progress->data : NULL;
444 
445  if (!progress || progress[field] >= n) return;
446 
447  p = f->owner->internal->thread_ctx;
448 
449  if (f->owner->debug&FF_DEBUG_THREADS)
450  av_log(f->owner, AV_LOG_DEBUG, "%p finished %d field %d\n", progress, n, field);
451 
453  progress[field] = n;
456 }
457 
458 void ff_thread_await_progress(ThreadFrame *f, int n, int field)
459 {
460  PerThreadContext *p;
461  int *progress = f->progress ? (int*)f->progress->data : NULL;
462 
463  if (!progress || progress[field] >= n) return;
464 
465  p = f->owner->internal->thread_ctx;
466 
467  if (f->owner->debug&FF_DEBUG_THREADS)
468  av_log(f->owner, AV_LOG_DEBUG, "thread awaiting %d field %d from %p\n", n, field, progress);
469 
471  while (progress[field] < n)
474 }
475 
477  PerThreadContext *p = avctx->internal->thread_ctx;
478 
479  if (!(avctx->active_thread_type&FF_THREAD_FRAME)) return;
480 
482  p->state = STATE_SETUP_FINISHED;
485 }
486 
488 static void park_frame_worker_threads(FrameThreadContext *fctx, int thread_count)
489 {
490  int i;
491 
492  for (i = 0; i < thread_count; i++) {
493  PerThreadContext *p = &fctx->threads[i];
494 
495  if (p->state != STATE_INPUT_READY) {
497  while (p->state != STATE_INPUT_READY)
500  }
501  }
502 }
503 
504 void ff_frame_thread_free(AVCodecContext *avctx, int thread_count)
505 {
506  FrameThreadContext *fctx = avctx->internal->thread_ctx;
507  const AVCodec *codec = avctx->codec;
508  int i;
509 
510  park_frame_worker_threads(fctx, thread_count);
511 
512  if (fctx->prev_thread && fctx->prev_thread != fctx->threads)
514 
515  fctx->die = 1;
516 
517  for (i = 0; i < thread_count; i++) {
518  PerThreadContext *p = &fctx->threads[i];
519 
523 
524  if (p->thread_init)
525  pthread_join(p->thread, NULL);
526 
527  if (codec->close)
528  codec->close(p->avctx);
529 
530  avctx->codec = NULL;
531 
533  av_frame_free(&p->frame);
534  }
535 
536  for (i = 0; i < thread_count; i++) {
537  PerThreadContext *p = &fctx->threads[i];
538 
545  av_freep(&p->buf);
547 
548  if (i) {
549  av_freep(&p->avctx->priv_data);
551  }
552 
553  av_freep(&p->avctx->internal);
554  av_freep(&p->avctx);
555  }
556 
557  av_freep(&fctx->threads);
559  av_freep(&avctx->internal->thread_ctx);
560 }
561 
563 {
564  int thread_count = avctx->thread_count;
565  const AVCodec *codec = avctx->codec;
566  AVCodecContext *src = avctx;
567  FrameThreadContext *fctx;
568  int i, err = 0;
569 
570 #if HAVE_W32THREADS
571  w32thread_init();
572 #endif
573 
574  if (!thread_count) {
575  int nb_cpus = av_cpu_count();
576  av_log(avctx, AV_LOG_DEBUG, "detected %d logical cores\n", nb_cpus);
577  // use number of cores + 1 as thread count if there is more than one
578  if (nb_cpus > 1)
579  thread_count = avctx->thread_count = FFMIN(nb_cpus + 1, MAX_AUTO_THREADS);
580  else
581  thread_count = avctx->thread_count = 1;
582  }
583 
584  if (thread_count <= 1) {
585  avctx->active_thread_type = 0;
586  return 0;
587  }
588 
589  avctx->internal->thread_ctx = fctx = av_mallocz(sizeof(FrameThreadContext));
590 
591  fctx->threads = av_mallocz(sizeof(PerThreadContext) * thread_count);
593  fctx->delaying = 1;
594 
595  for (i = 0; i < thread_count; i++) {
597  PerThreadContext *p = &fctx->threads[i];
598 
604 
605  p->frame = av_frame_alloc();
606  if (!p->frame) {
607  err = AVERROR(ENOMEM);
608  goto error;
609  }
610 
611  p->parent = fctx;
612  p->avctx = copy;
613 
614  if (!copy) {
615  err = AVERROR(ENOMEM);
616  goto error;
617  }
618 
619  *copy = *src;
620 
621  copy->internal = av_malloc(sizeof(AVCodecInternal));
622  if (!copy->internal) {
623  err = AVERROR(ENOMEM);
624  goto error;
625  }
626  *copy->internal = *src->internal;
627  copy->internal->thread_ctx = p;
628  copy->internal->pkt = &p->avpkt;
629 
630  if (!i) {
631  src = copy;
632 
633  if (codec->init)
634  err = codec->init(copy);
635 
636  update_context_from_thread(avctx, copy, 1);
637  } else {
638  copy->priv_data = av_malloc(codec->priv_data_size);
639  if (!copy->priv_data) {
640  err = AVERROR(ENOMEM);
641  goto error;
642  }
643  memcpy(copy->priv_data, src->priv_data, codec->priv_data_size);
644  copy->internal->is_copy = 1;
645 
646  if (codec->init_thread_copy)
647  err = codec->init_thread_copy(copy);
648  }
649 
650  if (err) goto error;
651 
653  p->thread_init = 1;
654  }
655 
656  return 0;
657 
658 error:
659  ff_frame_thread_free(avctx, i+1);
660 
661  return err;
662 }
663 
665 {
666  int i;
667  FrameThreadContext *fctx = avctx->internal->thread_ctx;
668 
669  if (!fctx) return;
670 
672  if (fctx->prev_thread) {
673  if (fctx->prev_thread != &fctx->threads[0])
675  }
676 
677  fctx->next_decoding = fctx->next_finished = 0;
678  fctx->delaying = 1;
679  fctx->prev_thread = NULL;
680  for (i = 0; i < avctx->thread_count; i++) {
681  PerThreadContext *p = &fctx->threads[i];
682  // Make sure decode flush calls with size=0 won't return old frames
683  p->got_frame = 0;
684  av_frame_unref(p->frame);
685 
687 
688  if (avctx->codec->flush)
689  avctx->codec->flush(p->avctx);
690  }
691 }
692 
694 {
695  PerThreadContext *p = avctx->internal->thread_ctx;
696  int err;
697 
698  f->owner = avctx;
699 
700  if (!(avctx->active_thread_type & FF_THREAD_FRAME))
701  return ff_get_buffer(avctx, f->f, flags);
702 
703  if (p->state != STATE_SETTING_UP &&
704  (avctx->codec->update_thread_context || !avctx->thread_safe_callbacks)) {
705  av_log(avctx, AV_LOG_ERROR, "get_buffer() cannot be called after ff_thread_finish_setup()\n");
706  return -1;
707  }
708 
709  if (avctx->internal->allocate_progress) {
710  int *progress;
711  f->progress = av_buffer_alloc(2 * sizeof(int));
712  if (!f->progress) {
713  return AVERROR(ENOMEM);
714  }
715  progress = (int*)f->progress->data;
716 
717  progress[0] = progress[1] = -1;
718  }
719 
722  if (avctx->thread_safe_callbacks || (
724  !avctx->get_buffer &&
725 #endif
728  err = ff_get_buffer(avctx, f->f, flags);
729  } else {
730  p->requested_frame = f->f;
731  p->requested_flags = flags;
732  p->state = STATE_GET_BUFFER;
735 
736  while (p->state != STATE_SETTING_UP)
738 
739  err = p->result;
740 
742 
743  }
744  if (!avctx->thread_safe_callbacks && !avctx->codec->update_thread_context)
745  ff_thread_finish_setup(avctx);
746 
747  if (err)
749 
751 
752  return err;
753 }
754 
756 {
757  PerThreadContext *p = avctx->internal->thread_ctx;
758  FrameThreadContext *fctx;
759  AVFrame *dst, *tmp;
761  int can_direct_free = !(avctx->active_thread_type & FF_THREAD_FRAME) ||
762  avctx->thread_safe_callbacks ||
763  (
765  !avctx->get_buffer &&
766 #endif
769 
770  if (!f->f->buf[0])
771  return;
772 
773  if (avctx->debug & FF_DEBUG_BUFFERS)
774  av_log(avctx, AV_LOG_DEBUG, "thread_release_buffer called on pic %p\n", f);
775 
777  f->owner = NULL;
778 
779  if (can_direct_free) {
780  av_frame_unref(f->f);
781  return;
782  }
783 
784  fctx = p->parent;
786 
787  if (p->num_released_buffers + 1 >= INT_MAX / sizeof(*p->released_buffers))
788  goto fail;
790  (p->num_released_buffers + 1) *
791  sizeof(*p->released_buffers));
792  if (!tmp)
793  goto fail;
794  p->released_buffers = tmp;
795 
797  av_frame_move_ref(dst, f->f);
798 
800 
801 fail:
803 }