virtualenv/FFmpeg
1
0
Fork 0
mirror of https://github.com/FFmpeg/FFmpeg.git synced 2024-12-28 20:53:54 +02:00
Code Issues Releases Activity

vp8: make wait/thread_mb_pos atomic.

Browse Source 
Fixes tsan warnings like this in fate-vp8-test-vector-007:

WARNING: ThreadSanitizer: data race (pid=3590)
  Write of size 4 at 0x7d8c0000e07c by thread T2:
    #0 decode_mb_row_no_filter src/libavcodec/vp8.c:2330 (ffmpeg+0x000000ffb59e)
[..]
  Previous write of size 4 at 0x7d8c0000e07c by thread T1:
    #0 decode_mb_row_no_filter src/libavcodec/vp8.c:2330 (ffmpeg+0x000000ffb59e)

(cherry picked from commit 9a54c6f243)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This commit is contained in:
Ronald S. Bultje 2017-04-05 16:18:54 -04:00 committed by Michael Niedermayer
parent 5e84c94f69
commit 9d742f774a
2 changed files with 18 additions and 17 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

29
libavcodec/vp8.c
View File

@ -2247,15 +2247,15 @@ static void vp8_decode_mv_mb_modes(AVCodecContext *avctx, VP8Frame *cur_frame,
#define check_thread_pos(td, otd, mb_x_check, mb_y_check) \
do { \
int tmp = (mb_y_check << 16) | (mb_x_check & 0xFFFF); \
if (otd->thread_mb_pos < tmp) { \
if (atomic_load(&otd->thread_mb_pos) < tmp) { \
pthread_mutex_lock(&otd->lock); \
td->wait_mb_pos = tmp; \
atomic_store(&td->wait_mb_pos, tmp); \
do { \
if (otd->thread_mb_pos >= tmp) \
if (atomic_load(&otd->thread_mb_pos) >= tmp) \
break; \
pthread_cond_wait(&otd->cond, &otd->lock); \
} while (1); \
td->wait_mb_pos = INT_MAX; \
atomic_store(&td->wait_mb_pos, INT_MAX); \
pthread_mutex_unlock(&otd->lock); \
} \
} while (0)
@ -2266,12 +2266,10 @@ static void vp8_decode_mv_mb_modes(AVCodecContext *avctx, VP8Frame *cur_frame,
int sliced_threading = (avctx->active_thread_type == FF_THREAD_SLICE) && \
(num_jobs > 1); \
int is_null = !next_td || !prev_td; \
int pos_check = (is_null) ? 1 \
: (next_td != td && \
pos >= next_td->wait_mb_pos) || \
(prev_td != td && \
pos >= prev_td->wait_mb_pos); \
td->thread_mb_pos = pos; \
int pos_check = (is_null) ? 1 : \
(next_td != td && pos >= atomic_load(&next_td->wait_mb_pos)) || \
(prev_td != td && pos >= atomic_load(&prev_td->wait_mb_pos)); \
atomic_store(&td->thread_mb_pos, pos); \
if (sliced_threading && pos_check) { \
pthread_mutex_lock(&td->lock); \
pthread_cond_broadcast(&td->cond); \
@ -2288,7 +2286,7 @@ static av_always_inline int decode_mb_row_no_filter(AVCodecContext *avctx, void
{
VP8Context *s = avctx->priv_data;
VP8ThreadData *prev_td, *next_td, *td = &s->thread_data[threadnr];
int mb_y = td->thread_mb_pos >> 16;
int mb_y = atomic_load(&td->thread_mb_pos) >> 16;
int mb_x, mb_xy = mb_y * s->mb_width;
int num_jobs = s->num_jobs;
VP8Frame *curframe = s->curframe, *prev_frame = s->prev_frame;
@ -2428,7 +2426,7 @@ static av_always_inline void filter_mb_row(AVCodecContext *avctx, void *tdata,
{
VP8Context *s = avctx->priv_data;
VP8ThreadData *td = &s->thread_data[threadnr];
int mb_x, mb_y = td->thread_mb_pos >> 16, num_jobs = s->num_jobs;
int mb_x, mb_y = atomic_load(&td->thread_mb_pos) >> 16, num_jobs = s->num_jobs;
AVFrame *curframe = s->curframe->tf.f;
VP8Macroblock *mb;
VP8ThreadData *prev_td, *next_td;
@ -2507,7 +2505,7 @@ int vp78_decode_mb_row_sliced(AVCodecContext *avctx, void *tdata, int jobnr,
td->thread_nr = threadnr;
for (mb_y = jobnr; mb_y < s->mb_height; mb_y += num_jobs) {
td->thread_mb_pos = mb_y << 16;
atomic_store(&td->thread_mb_pos, mb_y << 16);
ret = s->decode_mb_row_no_filter(avctx, tdata, jobnr, threadnr);
if (ret < 0) {
update_pos(td, s->mb_height, INT_MAX & 0xFFFF);
@ -2667,8 +2665,9 @@ int vp78_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
s->mv_min.y = -MARGIN;
s->mv_max.y = ((s->mb_height - 1) << 6) + MARGIN;
for (i = 0; i < MAX_THREADS; i++) {
s->thread_data[i].thread_mb_pos = 0;
s->thread_data[i].wait_mb_pos = INT_MAX;
VP8ThreadData *td = &s->thread_data[i];
atomic_init(&td->thread_mb_pos, 0);
atomic_init(&td->wait_mb_pos, INT_MAX);
}
if (is_vp7)
avctx->execute2(avctx, vp7_decode_mb_row_sliced, s->thread_data, NULL,

6
libavcodec/vp8.h
View File

@ -26,6 +26,8 @@
#ifndef AVCODEC_VP8_H
#define AVCODEC_VP8_H
#include <stdatomic.h>
#include "libavutil/buffer.h"
#include "libavutil/thread.h"
@ -114,8 +116,8 @@ typedef struct VP8ThreadData {
pthread_mutex_t lock;
pthread_cond_t cond;
#endif
int thread_mb_pos; // (mb_y << 16) | (mb_x & 0xFFFF)
int wait_mb_pos; // What the current thread is waiting on.
atomic_int thread_mb_pos; // (mb_y << 16) | (mb_x & 0xFFFF)
atomic_int wait_mb_pos; // What the current thread is waiting on.
#define EDGE_EMU_LINESIZE 32
DECLARE_ALIGNED(16, uint8_t, edge_emu_buffer)[21 * EDGE_EMU_LINESIZE];