[Spice-devel] [PATCH v1 2/5] dcc: Create a stream associated with gl_draw for non-gl clients

[Frediano Ziglio]

Il giorno gio 16 mar 2023 alle ore 06:05 Vivek Kasireddy
<vivek.kasireddy at intel.com> ha scritto:
>
> For non-gl/remote clients, if a stream does not exist or if any
> of the key parameters associated with gl_draw such as x/y or
> width/height are changed, then we create a new stream. Otherwise,
> we just update the current stream's timestamp.
>
> Cc: Gerd Hoffmann <kraxel at redhat.com>
> Cc: Marc-André Lureau <marcandre.lureau at redhat.com>
> Cc: Dongwon Kim <dongwon.kim at intel.com>
> Signed-off-by: Vivek Kasireddy <vivek.kasireddy at intel.com>
> ---
>  server/dcc-private.h    |  2 ++
>  server/dcc.cpp          | 14 +++++++++++++
>  server/video-stream.cpp | 44 +++++++++++++++++++++++++++++++++++++++++
>  server/video-stream.h   |  2 ++
>  4 files changed, 62 insertions(+)
>
> diff --git a/server/dcc-private.h b/server/dcc-private.h
> index bf485aec..cd5b76a3 100644
> --- a/server/dcc-private.h
> +++ b/server/dcc-private.h
> @@ -69,6 +69,8 @@ struct DisplayChannelClientPrivate
>      uint32_t streams_max_latency;
>      uint64_t streams_max_bit_rate;
>      bool gl_draw_ongoing;
> +
> +    VideoStream *gl_draw_stream;

This raw pointer smells pretty bad. Defined here seems also to
indicate that every client could have a different draw stream, which
seems wrong.

>  };
>
>  #include "pop-visibility.h"
> diff --git a/server/dcc.cpp b/server/dcc.cpp
> index f0b355ca..9d91ca53 100644
> --- a/server/dcc.cpp
> +++ b/server/dcc.cpp
> @@ -525,6 +525,20 @@ RedPipeItemPtr dcc_gl_draw_item_new(RedChannelClient *rcc, void *data, int num)
>      auto item = red::make_shared<RedGlDrawItem>();
>      item->draw = *draw;
>
> +    if (!dcc_is_gl_client(dcc)) {
> +        VideoStream *stream = dcc->priv->gl_draw_stream;
> +
> +        if (!stream ||
> +            stream->dest_area.left != draw->x ||
> +            stream->dest_area.top != draw->y ||
> +            stream->width != draw->w || stream->height != draw->h) {
> +            stream = display_channel_create_gl_draw_stream(dcc, draw);
> +        } else {
> +            stream->last_time = spice_get_monotonic_time_ns();
> +        }
> +        dcc->priv->gl_draw_stream = stream;

This rewrite with a create and not a destroy looks like a leak.
Why assign it even if you are not changing it?

> +    }
> +
>      return item;
>  }
>
> diff --git a/server/video-stream.cpp b/server/video-stream.cpp
> index 056d0c31..03a7d68d 100644
> --- a/server/video-stream.cpp
> +++ b/server/video-stream.cpp
> @@ -415,6 +415,47 @@ static void display_channel_create_stream(DisplayChannel *display, Drawable *dra
>                  stream->input_fps);
>  }
>
> +VideoStream *
> +display_channel_create_gl_draw_stream(DisplayChannelClient *dcc,
> +                                      const SpiceMsgDisplayGlDraw *draw)
> +{
> +    DisplayChannel *display = DCC_TO_DC(dcc);
> +    VideoStream *stream;
> +    SpiceRect dest_area = {
> +        .left = draw->x,
> +        .top = draw->y,
> +        .right = draw->w,
> +        .bottom = draw->h
> +    };
> +
> +    if (!(stream = display_channel_stream_try_new(display))) {
> +        return nullptr;
> +    }
> +
> +    ring_add(&display->priv->streams, &stream->link);
> +    stream->current = nullptr;
> +    stream->last_time = spice_get_monotonic_time_ns();
> +    stream->width = draw->w;
> +    stream->height = draw->h;
> +    stream->dest_area = dest_area;
> +    stream->refs = 1;
> +    stream->top_down = 1;
> +    stream->input_fps = MAX_FPS;
> +    stream->num_input_frames = 0;
> +    stream->input_fps_start_time = spice_get_monotonic_time_ns();
> +    display->priv->streams_size_total += stream->width * stream->height;
> +    display->priv->stream_count++;
> +
> +    dcc_create_stream(dcc, stream);
> +    spice_debug("stream %d %dx%d (%d, %d) (%d, %d) %u fps",
> +                display_channel_get_video_stream_id(display, stream), stream->width,
> +                stream->height, stream->dest_area.left, stream->dest_area.top,
> +                stream->dest_area.right, stream->dest_area.bottom,
> +                stream->input_fps);
> +
> +    return stream;
> +}
> +

This looks like a big copy&paste from another function. Could we not
reuse some code?

>  // returns whether a stream was created
>  static bool video_stream_add_frame(DisplayChannel *display,
>                               Drawable *frame_drawable,
> @@ -744,6 +785,9 @@ void dcc_create_stream(DisplayChannelClient *dcc, VideoStream *stream)
>      if (stream->current) {
>          region_clone(&agent->vis_region, &stream->current->tree_item.base.rgn);
>          region_clone(&agent->clip, &agent->vis_region);
> +    } else {
> +        region_add(&agent->vis_region, &stream->dest_area);
> +        region_clone(&agent->clip, &agent->vis_region);
>      }
>      agent->dcc = dcc;
>
> diff --git a/server/video-stream.h b/server/video-stream.h
> index 23b44ff5..a8b2c61c 100644
> --- a/server/video-stream.h
> +++ b/server/video-stream.h
> @@ -124,6 +124,8 @@ struct VideoStream {
>  };
>
>  void display_channel_init_video_streams(DisplayChannel *display);
> +VideoStream *display_channel_create_gl_draw_stream(DisplayChannelClient *dcc,
> +                                                   const SpiceMsgDisplayGlDraw *draw);
>  void video_stream_stop(DisplayChannel *display, VideoStream *stream);
>  void video_stream_trace_update(DisplayChannel *display, Drawable *drawable);
>  void video_stream_maintenance(DisplayChannel *display, Drawable *candidate,
> --
> 2.37.2
>