[FFmpeg-devel] [PATCH 2/7] lavc/vaapi_encode_h264: Enable macro block level bit rate control.

[mypopy at gmail.com]

On Tue, Nov 6, 2018 at 3:40 AM Mark Thompson <sw at jkqxz.net> wrote:
>
> On 03/11/18 02:52, Jun Zhao wrote:
> > Enables macro block level bit rate control, that generally improves
> > subjective visual quality. It may have a negative impact on
> > performance and objective visual quality metrics. Default is off
> > and can't compatible with Constant QP.
> >
> > Signed-off-by: Jun Zhao <jun.zhao at intel.com>
> > ---
> >  libavcodec/vaapi_encode_h264.c |   21 +++++++++++++++++++++
> >  1 files changed, 21 insertions(+), 0 deletions(-)
> >
> > diff --git a/libavcodec/vaapi_encode_h264.c b/libavcodec/vaapi_encode_h264.c
> > index 7bb77cf..060277b 100644
> > --- a/libavcodec/vaapi_encode_h264.c
> > +++ b/libavcodec/vaapi_encode_h264.c
> > @@ -58,6 +58,7 @@ typedef struct VAAPIEncodeH264Context {
> >      int sei;
> >      int profile;
> >      int level;
> > +    int mb_rate_control;
> >
> >      // Derived settings.
> >      int mb_width;
> > @@ -889,6 +890,22 @@ static av_cold int vaapi_encode_h264_configure(AVCodecContext *avctx)
> >      return 0;
> >  }
> >
> > +static av_cold int vaapi_encode_h264_bit_rate_control(AVCodecContext *avctx)
> > +{
> > +    VAAPIEncodeContext      *ctx = avctx->priv_data;
> > +    VAAPIEncodeH264Context *priv = avctx->priv_data;
> > +
> > +    if (priv->mb_rate_control) {
> > + #if VA_CHECK_VERSION(0, 39, 2)
> > +        ctx->rc_params.rc.rc_flags.bits.mb_rate_control = priv->mb_rate_control;
> > + #else
> > +        av_log(avctx, AV_LOG_WARNING, "The MB rate control option is not "
> > +               "supported with this VAAPI version.\n");
> > + #endif
> > +    }
> > +    return 0;
> > +}
> > +
> >  static const VAAPIEncodeProfile vaapi_encode_h264_profiles[] = {
> >      { FF_PROFILE_H264_HIGH, 8, 3, 1, 1, VAProfileH264High },
> >      { FF_PROFILE_H264_MAIN, 8, 3, 1, 1, VAProfileH264Main },
> > @@ -904,6 +921,8 @@ static const VAAPIEncodeType vaapi_encode_type_h264 = {
> >
> >      .configure             = &vaapi_encode_h264_configure,
> >
> > +    .bit_rate_control      = &vaapi_encode_h264_bit_rate_control,
> > +
> >      .sequence_params_size  = sizeof(VAEncSequenceParameterBufferH264),
> >      .init_sequence_params  = &vaapi_encode_h264_init_sequence_params,
> >
> > @@ -1001,6 +1020,8 @@ static const AVOption vaapi_encode_h264_options[] = {
> >        OFFSET(qp), AV_OPT_TYPE_INT, { .i64 = 20 }, 0, 52, FLAGS },
> >      { "quality", "Set encode quality (trades off against speed, higher is faster)",
> >        OFFSET(quality), AV_OPT_TYPE_INT, { .i64 = -1 }, -1, INT_MAX, FLAGS },
> > +    { "mb_rate_control", "MB level bitrate control (only supported on GEN9+)",
> > +      OFFSET(mb_rate_control), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, FLAGS, "mb_rate_control" },
> >      { "coder", "Entropy coder type",
> >        OFFSET(coder), AV_OPT_TYPE_INT, { .i64 = 1 }, 0, 1, FLAGS, "coder" },
> >          { "cavlc", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = 0 }, INT_MIN, INT_MAX, FLAGS, "coder" },
> >
>
> Enabling this option still completely kills the GPU on my Skylake (6300) test machine (in I think older kernel versions this also caused the whole machine to hard-reset immediately, in current ones it only kills the GPU requiring a reboot to fix).  See <https://github.com/intel/intel-vaapi-driver/issues/172>.
>
> - Mark
>
>
> E.g., from 4.18.10:
>
> [  138.818477] [drm] GPU HANG: ecode 9:0:0x8fd8ffff, in ffmpeg_g [595], reason: hang on rcs0, action: reset
> [  138.819029] [drm] GPU hangs can indicate a bug anywhere in the entire gfx stack, including userspace.
> [  138.819604] [drm] Please file a _new_ bug report on bugs.freedesktop.org against DRI -> DRM/Intel
> [  138.820190] [drm] drm/i915 developers can then reassign to the right component if it's not a kernel issue.
> [  138.820787] [drm] The gpu crash dump is required to analyze gpu hangs, so please always attach it.
> [  138.821394] [drm] GPU crash dump saved to /sys/class/drm/card0/error
> [  138.822022] i915 0000:00:02.0: Resetting rcs0 for hang on rcs0
> [  146.811837] i915 0000:00:02.0: Resetting rcs0 for hang on rcs0
> [  146.815773] [drm:gen8_reset_engines [i915]] *ERROR* rcs0: reset request timeout
> [  146.817686] i915 0000:00:02.0: Resetting chip for hang on rcs0
> [  146.819565] [drm:gen8_reset_engines [i915]] *ERROR* rcs0: reset request timeout
> [  146.929115] [drm:gen8_reset_engines [i915]] *ERROR* rcs0: reset request timeout
> [  147.041196] [drm:gen8_reset_engines [i915]] *ERROR* rcs0: reset request timeout
> [  147.151935] i915 0000:00:02.0: Failed to reset chip
> [  147.156055] [drm:gen8_reset_engines [i915]] *ERROR* rcs0: reset request timeout
>
I know this GPU hang issue in i965 driver, but i965 drvier is slow
down and  will switch the GPU driver to
iHD(https://github.com/intel/media-driver), I don't know who will fix
this issue in i965.