08.07.2023 00:31, Gurchetan Singh пишет: > We don't want to create a fence for every command submission. It's > only necessary when userspace provides a waitable token for submission. > This could be: > > 1) bo_handles, to be used with VIRTGPU_WAIT > 2) out_fence_fd, to be used with dma_fence apis > 3) a ring_idx provided with VIRTGPU_CONTEXT_PARAM_POLL_RINGS_MASK > + DRM event API > 4) syncobjs in the future > > The use case for just submitting a command to the host, and expecting > no response. For example, gfxstream has GFXSTREAM_CONTEXT_PING that > just wakes up the host side worker threads. There's also > CROSS_DOMAIN_CMD_SEND which just sends data to the Wayland server. > > This prevents the need to signal the automatically created > virtio_gpu_fence. > > In addition, VIRTGPU_EXECBUF_RING_IDX is checked when creating a > DRM event object. VIRTGPU_CONTEXT_PARAM_POLL_RINGS_MASK is > already defined in terms of per-context rings. It was theoretically > possible to create a DRM event on the global timeline (ring_idx == 0), > if the context enabled DRM event polling. However, that wouldn't > work and userspace (Sommelier). Explicitly disallow it for > clarity. > > Signed-off-by: Gurchetan Singh <gurchetansingh@xxxxxxxxxxxx> > --- > v2: Fix indent (Dmitry) > v3: Refactor drm fence event checks to avoid possible NULL deref (Dmitry) > v4: More detailed commit message about addition drm fence event checks (Dmitry) > > drivers/gpu/drm/virtio/virtgpu_submit.c | 28 +++++++++++++------------ > 1 file changed, 15 insertions(+), 13 deletions(-) Applied to misc-next -- Best regards, Dmitry
