tree 1e888fa32ab36d9d22238ec6bb55a7b9a51040e3
parent a62f8e402c081cd38307863d813cf7712a492a3b
author Sunny Sachanandani <sunnyps@chromium.org> 1641947317 +0000
committer Dawn LUCI CQ <dawn-scoped@luci-project-accounts.iam.gserviceaccount.com> 1641947317 +0000

d3d12: Acquire/release keyed mutex around ExecuteCommandLists

D3D keyed mutex cannot be acquired recursively and therefore external
D3D textures cannot be concurrently read within Dawn (e.g. multiple
imports of the same video frame) or across Dawn and GL (e.g. both WebGPU
and WebGL importing a video frame).

Within Dawn, we can scope keyed mutex acquire/release to command list
submission so that Chromium can always guarantee that Dawn doesn't hold
access to any resources after running Dawn wire commands. We also check
that keyed mutexes aren't recursively acquired in Dawn by keeping track
of the acquire count per resource.

This solves the multiple acquire problem within Dawn and provides a path
for concurrent read access across Dawn and GL once the GL decoders are
changed so that they also don't hold access to resources after switching
contexts.

Bug: chromium:1241533
Change-Id: If88fd4a4f798b972836a134809e4fed8832ec89c
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/75644
Reviewed-by: Loko Kung <lokokung@google.com>
Commit-Queue: Sunny Sachanandani <sunnyps@chromium.org>
Auto-Submit: Sunny Sachanandani <sunnyps@chromium.org>
Reviewed-by: Austin Eng <enga@chromium.org>
Commit-Queue: Austin Eng <enga@chromium.org>