[FFmpeg-devel] [PATCH v1] avcodec/v410dec: add the frame and slice threading support

[James Almer]

On 10/25/2019 12:36 PM, lance.lmwang at gmail.com wrote:
> From: Limin Wang <lance.lmwang at gmail.com>
> 
> 1, Test server configure:
> [root at localhost ~]# cat /proc/cpuinfo  |grep "model name"
> model name	: Intel(R) Xeon(R) CPU E5-2650 v2 @ 2.60GHz
> model name	: Intel(R) Xeon(R) CPU E5-2650 v2 @ 2.60GHz
> ...
> 
> [root at localhost ~]# free -h
>               total        used        free      shared  buff/cache   available
> Mem:           102G        997M         93G         16M        7.6G        100G
> 
> 2, performance profiling
> master:
> ./ffmpeg -y -stream_loop 100 -i ./test.avi -benchmark -f null -
> video:529kB audio:40602kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown
> bench: utime=16.932s stime=9.417s rtime=26.341s
> bench: maxrss=271056kB
> frame= 1010 fps= 38 q=-0.0 Lsize=N/A time=00:03:36.54 bitrate=N/A speed=8.22x
> 
> patch applied:
> ./ffmpeg -y -threads 2 -thread_type slice+frame -stream_loop 100 -i ./test.avi -benchmark -f null -
> frame= 1010 fps= 52 q=-0.0 Lsize=N/A time=00:03:36.54 bitrate=N/A speed=11.1x
> video:529kB audio:40602kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown
> bench: utime=23.164s stime=10.983s rtime=19.503s
> bench: maxrss=338252kB
> 
> ./ffmpeg -y -threads 4 -thread_type slice+frame -stream_loop 100 -i ./test.avi -benchmark -f null -
> frame= 1010 fps= 71 q=-0.0 Lsize=N/A time=00:03:36.54 bitrate=N/A speed=15.3x
> video:529kB audio:40602kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown
> bench: utime=21.610s stime=11.603s rtime=14.160s
> bench: maxrss=517060kB

Can you try with slice threading? -thread_type slice+frame will default
to frame, since afaik both can't run at the same time.

> 
> 
> Signed-off-by: Limin Wang <lance.lmwang at gmail.com>
> ---
>  libavcodec/v410dec.c | 72 +++++++++++++++++++++++++++++++-------------
>  1 file changed, 51 insertions(+), 21 deletions(-)
> 
> diff --git a/libavcodec/v410dec.c b/libavcodec/v410dec.c
> index 48fab68273..7ad5eb8fb5 100644
> --- a/libavcodec/v410dec.c
> +++ b/libavcodec/v410dec.c
> @@ -24,6 +24,13 @@
>  #include "libavutil/intreadwrite.h"
>  #include "avcodec.h"
>  #include "internal.h"
> +#include "thread.h"
> +
> +typedef struct ThreadData {
> +    AVFrame *frame;
> +    uint8_t *buf;
> +    int stride;
> +} ThreadData;
>  
>  static av_cold int v410_decode_init(AVCodecContext *avctx)
>  {
> @@ -42,31 +49,24 @@ static av_cold int v410_decode_init(AVCodecContext *avctx)
>      return 0;
>  }
>  
> -static int v410_decode_frame(AVCodecContext *avctx, void *data,
> -                             int *got_frame, AVPacket *avpkt)
> +static int v410_decode_slice(AVCodecContext *avctx, void *arg, int jobnr, int threadnr)
>  {
> -    AVFrame *pic = data;
> -    uint8_t *src = avpkt->data;
> +    ThreadData *td = arg;
> +    AVFrame *pic = td->frame;
> +    int stride = td->stride;
> +    int thread_count = av_clip(avctx->thread_count, 1, avctx->height/4);
> +    int slice_start = (avctx->height *  jobnr) / thread_count;
> +    int slice_end = (avctx->height * (jobnr+1)) / thread_count;
> +    const uint8_t *src = td->buf + stride * slice_start;
>      uint16_t *y, *u, *v;
>      uint32_t val;
> -    int i, j, ret;
> -
> -    if (avpkt->size < 4 * avctx->height * avctx->width) {
> -        av_log(avctx, AV_LOG_ERROR, "Insufficient input data.\n");
> -        return AVERROR(EINVAL);
> -    }
> -
> -    if ((ret = ff_get_buffer(avctx, pic, 0)) < 0)
> -        return ret;
> +    int i, j;
>  
> -    pic->key_frame = 1;
> -    pic->pict_type = AV_PICTURE_TYPE_I;
> +    y = (uint16_t*)pic->data[0] + slice_start * (pic->linesize[0] >> 1);
> +    u = (uint16_t*)pic->data[1] + slice_start * (pic->linesize[1] >> 1);
> +    v = (uint16_t*)pic->data[2] + slice_start * (pic->linesize[2] >> 1);
>  
> -    y = (uint16_t *)pic->data[0];
> -    u = (uint16_t *)pic->data[1];
> -    v = (uint16_t *)pic->data[2];
> -
> -    for (i = 0; i < avctx->height; i++) {
> +    for (i = slice_start; i < slice_end; i++) {
>          for (j = 0; j < avctx->width; j++) {
>              val = AV_RL32(src);
>  
> @@ -82,6 +82,35 @@ static int v410_decode_frame(AVCodecContext *avctx, void *data,
>          v += pic->linesize[2] >> 1;
>      }
>  
> +    return 0;
> +}
> +
> +static int v410_decode_frame(AVCodecContext *avctx, void *data,
> +                             int *got_frame, AVPacket *avpkt)
> +{
> +    ThreadData td;
> +    ThreadFrame frame = { .f = data };
> +    AVFrame *pic = data;
> +    uint8_t *src = avpkt->data;
> +    int ret;
> +    int thread_count = av_clip(avctx->thread_count, 1, avctx->height/4);
> +
> +    td.stride = avctx->width * 4;
> +    if (avpkt->size < 4 * avctx->height * avctx->width) {
> +        av_log(avctx, AV_LOG_ERROR, "Insufficient input data.\n");
> +        return AVERROR(EINVAL);
> +    }
> +
> +    if ((ret = ff_thread_get_buffer(avctx, &frame, 0)) < 0)
> +        return ret;
> +
> +    pic->key_frame = 1;
> +    pic->pict_type = AV_PICTURE_TYPE_I;
> +
> +    td.buf = src;
> +    td.frame = pic;
> +    avctx->execute2(avctx, v410_decode_slice, &td, NULL, thread_count);
> +
>      *got_frame = 1;
>  
>      return avpkt->size;
> @@ -94,5 +123,6 @@ AVCodec ff_v410_decoder = {
>      .id           = AV_CODEC_ID_V410,
>      .init         = v410_decode_init,
>      .decode       = v410_decode_frame,
> -    .capabilities = AV_CODEC_CAP_DR1,
> +    .capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_SLICE_THREADS |
> +                    AV_CODEC_CAP_FRAME_THREADS
>  };
>