tree aa982776c6f1cf12c9e85b4eba2ec6d057096d95
parent 0b643a101034e9dd54ce21a356df66a49f536289
author Sunny Sachanandani <sunnyps@chromium.org> 1690255044 +0000
committer Dawn LUCI CQ <dawn-scoped@luci-project-accounts.iam.gserviceaccount.com> 1690255044 +0000

d3d11: Use D3D11 multithread protection

With Graphite on Dawn D3D11 backend, Chrome's media stack uses the same
D3D11 device as Graphite and has no way of synchronizing access to the
immediate context which is otherwise protected internally in Dawn using
a device scoped mutex.

Using ID3D11Multithread::SetMultithreadProtected(TRUE) enables locking
in D3D11 which helps with this, but it has significant overhead since it
acquires/releases a mutex for every API call. However, ID3D11Multithread
provides Enter/Leave methods which allow putting entire sequences of
calls in a critical section minimizing the overhead of using the mutex.

This CL does the following:

1) Call SetMultithreadProtected(TRUE) if D3D11MultithreadProtected
   feature is enabled.

2) Provide a ScopedCriticalSection helper for CommandRecordingContext
   that calls Enter/Leave. This is used by d3d11 CommandBuffer::Execute
   to mark the entire command processing loop as a critical section.

3) In TickImpl, add the debug layer error collection call to before
   NextSerial so it's not skipped if NextSerial fails.

Bug: dawn:1927, chromium:1464550
Change-Id: Ic0a3185d9e3d623a82058142fef4e010da054125
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/142540
Auto-Submit: Sunny Sachanandani <sunnyps@chromium.org>
Reviewed-by: Austin Eng <enga@chromium.org>
Kokoro: Kokoro <noreply+kokoro@google.com>
Commit-Queue: Sunny Sachanandani <sunnyps@chromium.org>