[Spice-devel] [PATCH v1 0/5] dcc: Create a stream for non-gl/remote clients that want to use dmabuf

Fri Mar 31 07:52:31 UTC 2023

Hi Frediano,

> 
> Il giorno lun 27 mar 2023 alle ore 07:53 Kasireddy, Vivek
> <vivek.kasireddy at intel.com> ha scritto:
> >
> > Hi Frediano,
> >
> > >    I was trying the patch series but the client keeps crashing. I
> > > tried different versions of remote-viewer (from Fedora and from
> > > Ubuntu) and they both crashed.
> > > On host I installed Intel VA drivers , Gstreamer VAAPIs and forced
> > > gstreamer:h264 as encoder.
> > [Kasireddy, Vivek] I don't think any of these packages are needed if we are
> testing
> > with a software (i.e, CPU-based) encoder/decoder (i.e, using x264enc/x264dec
> plugins).
> 
> They should allow hardware encoding.
[Kasireddy, Vivek] IIUC, currently, Spice only uses x264enc/x264dec plugins and
with these only software encoding is possible. We need to use different plugins to
enable hardware encoding. For instance we need to use either vaapih264enc or
msdkh264enc on Intel hardware. As I mentioned earlier, we are planning to
add this support.

> 
> > On my Fedora 37, these relevant plugins are provided by:
> > # rpm -q --whatprovides /usr/lib64/gstreamer-1.0/libgstx264.so
> > gstreamer1-plugins-ugly-1.20.5-1.fc37.x86_64
> > # rpm -q --whatprovides /usr/lib64/gstreamer-1.0/libgstlibav.so
> > gstreamer1-plugin-libav-1.20.5-1.fc37.x86_64
> >
> > The former provides x264enc and the latter provides x264dec. You can either
> choose
> > the ones provided by your distro or build Gstreamer with -Dgst-plugins-
> ugly:x264=enabled
> > and -Dlibav=enabled. However, note that one of our eventual goals is to cleanly
> add a
> > new Gstreamer pipeline to Spice to provide users an option for hardware-based
> > (i.e, GPU assisted) H.264 encoding/decoding using msdkh264enc/msdkh264dec
> plugins:
> > https://gstreamer.freedesktop.org/documentation/msdk/msdkh264enc.html?gi-
> language=c
> >
> > > Anything else you need to do?
> > [Kasireddy, Vivek] Sorry, I was not expecting anyone would test the Spice server
> > patches and therefore did not provide all the required information to test them.
> > Anyway, I suspect the reason for your remote-viewer crash is because there is no
> > (primary) surface created. Here is the tentative Qemu patch that does just that:
> >
> 
> Do you have a branch for Qemu somewhere?
[Kasireddy, Vivek] Yes, I created one here:
https://gitlab.freedesktop.org/Vivek/qemu/-/commits/pref_codec1
https://gitlab.freedesktop.org/Vivek/spice/-/commits/encode_dmabuf1

And, FYI, here is my exact qemu launch cmd (on Fedora 37):
./qemu-system-x86_64 -m 4096m -enable-kvm -cpu host -smp cores=8 -drive file=./fed30kvm.img,format=qcow2,cache=none -vga none -device e1000,netdev=net0,mac=DE:AD:BE:EF:BF:FA -netdev tap,id=net0,ifname=tap0,script=no,downscript=no -device virtio-gpu-pci,max_outputs=1,blob=true,xres=1920,yres=1080 -spice port=3001,gl=on,disable-ticketing=on,preferred-codec=gstreamer:h264 -object memory-backend-memfd,id=mem1,size=4096M -machine memory-backend=mem1 -usb -device usb-tablet -serial stdio

> 
> >          fd = egl_get_fd_for_texture(ssd->ds->texture,
> >
> > I did not yet post this patch to the Qemu mailing list because I still need to
> implement
> > feature negotiation between Qemu and Spice to auto-detect this capability. And,
> > in addition to this patch, you also need the patch that adds the "preferred-codec"
> > option to Qemu, unless you are hardcoding it in Spice:
> > https://lists.nongnu.org/archive/html/qemu-devel/2023-01/msg04999.html
> >
> 
> Yes, I hardcoded that in SPICE. Note that I posted a comment in that
> commit, I think it's valid as it is.
> Also I think it should not change the SPICE default.
[Kasireddy, Vivek] Yes, I noted your comment; I'll make the change in the
next version.

Thanks,
Vivek

> 
> > Lastly, not sure if it makes a difference, but here are the relevant options I am
> > using to launch Qemu:
> > -device virtio-gpu-pci,max_outputs=1,blob=true,xres=1920,yres=1080
> > -spice port=3001,gl=on,disable-ticketing=on,preferred-codec=gstreamer:h264
> > -object memory-backend-memfd,id=mem1,size=4096M
> > -machine memory-backend=mem1 -usb -device usb-tablet -serial stdio
> >
> > Thanks,
> > Vivek
> >
> 
> I will try again.
> 
> Thanks,
>   Frediano
> 
> > >
> > > On the logs I find:
> > >
> > > 2023-03-25T19:31:36.034007Z qemu-system-x86_64: warning: Spice:
> > > ../server/dcc-send.cpp:1786:red_marshall_gl_draw_stream: bad return
> > > value (0) from VideoEncoder::encode_dmabuf
> > > 2023-03-25T19:31:37.064219Z qemu-system-x86_64: warning: spice: no
> > > gl-draw-done within one second
> > > 2023-03-25T19:31:58.214387Z qemu-system-x86_64: warning: Spice:
> > > Connection reset by peer
> > > 2023-03-25T19:31:58.214482Z qemu-system-x86_64: warning: Spice:
> > > Connection reset by peer
> > > 2023-03-25T19:31:58.214580Z qemu-system-x86_64: warning: Spice:
> > > Connection reset by peer
> > > 2023-03-25T19:31:58.214642Z 2023-03-25T19:31:58.214636Z
> > > qemu-system-x86_64:qemu-system-x86_64:  warning: Spice: Connection
> > > reset by peer
> > > warning: Spice: display:0 (0x55947e76fd10): Connection reset by peer
> > > 2023-03-25T19:31:58.214721Z qemu-system-x86_64: warning: Spice:
> > > Connection reset by peer
> > > 2023-03-25T19:31:58.214841Z qemu-system-x86_64: warning: Spice:
> > > Connection reset by peer
> > > 2023-03-25T19:31:58.215057Z qemu-system-x86_64: warning: Spice:
> > > Connection reset by peer
> > >
> > > 0 value from encode_dmabuf should mean
> VIDEO_ENCODER_FRAME_DROP.
> > >
> > > Regards,
> > >    Frediano
> > >
> > > Il giorno gio 16 mar 2023 alle ore 06:05 Vivek Kasireddy
> > > <vivek.kasireddy at intel.com> ha scritto:
> > > >
> > > > For clients that cannot accept a dmabuf fd directly (such as those
> > > > running on a remote system), this patch series provides a way for
> > > > the Spice server to stream the gl/dmabuf data/buffer instead. This
> > > > is mostly done by enabling the creation of Gst memory using a dmabuf
> > > > fd as the source. This ability is useful given that dmabuf is the
> > > > standard mechanism for sharing buffers between various drivers and
> > > > userspace in many Graphics and Media usecases. Currently, this is
> > > > only used/tested with Qemu and remote-viewer using the x264enc/dec
> > > > codec to stream the Guest/VM desktop but it can be easily extended
> > > > to other plugins and applications.
> > > >
> > > > Here is roughly how things work:
> > > > - The application (e.g, Qemu) chooses its preferred codec (a Gstreamer
> > > >   one) and calls gl_scanout (to update the fd) followed by gl_draw.
> > > > - In response, the Spice server checks to see if the client is capable
> > > >   of accepting a dmabuf fd directly or not. If yes, the fd is forwarded
> > > >   directly to the client; otherwise, a new stream is created.
> > > > - The Spice server then sends the dmabuf fd to the Gstreamer encoder
> > > >   which uses it as an input for creating an encoded buffer which is then
> > > >   sent to the client.
> > > > - Once the encoding process is done, an async completion cookie is sent
> > > >   to the application.
> > > >
> > > > Here is a link to the previous version that used a drawable to share
> > > > the dmabuf fd with the Gstreamer encoder:
> > > > https://lists.freedesktop.org/archives/spice-devel/2023-January/052948.html
> > > >
> > > > Cc: Frediano Ziglio <freddy77 at gmail.com>
> > > > Cc: Gerd Hoffmann <kraxel at redhat.com>
> > > > Cc: Marc-André Lureau <marcandre.lureau at redhat.com>
> > > > Cc: Dongwon Kim <dongwon.kim at intel.com>
> > > >
> > > > Vivek Kasireddy (5):
> > > >   dcc: Check to see if the client supports multiple codecs
> > > >   dcc: Create a stream associated with gl_draw for non-gl clients
> > > >   dcc-send: Encode and send gl_draw stream data to the remote client
> > > >   gstreamer-encoder: Add an encoder function that takes dmabuf fd as
> > > >     input
> > > >   video-stream: Don't stop a stream if a gl_draw operation is pending
> > > >
> > > >  meson.build                      |   2 +-
> > > >  server/dcc-private.h             |   4 ++
> > > >  server/dcc-send.cpp              |  89 ++++++++++++++++++++++-
> > > >  server/dcc.cpp                   |  36 +++++++---
> > > >  server/display-channel-private.h |   6 ++
> > > >  server/gstreamer-encoder.c       | 119
> ++++++++++++++++++++++++++++++-
> > > >  server/video-encoder.h           |  13 ++++
> > > >  server/video-stream.cpp          |  65 ++++++++++++++++-
> > > >  server/video-stream.h            |   2 +
> > > >  9 files changed, 319 insertions(+), 17 deletions(-)
> > > >
> > > > --
> > > > 2.37.2
> > > >