commit c9a22bcb93db27e200a184c1f7b9bf0f288815c7
author Hao Li <hao.x.li@intel.com> Fri Jan 08 22:56:05 2021 +0000
committer Commit Bot service account <commit-bot@chromium.org> Fri Jan 08 22:56:05 2021 +0000
tree 0ae17c341f0695c4a56d2b22f1eaf05ee6f1437b
parent c4efeef8333435ef770fdf72f3ffdca9d7d19bfc

Disable timestamp query extension on Metal

Currently it's not clear how to convert timestamps to nanoseconds on
Metal, disable timestamp query extension on Metal until we know how to
do that. WebGPU issue: https://github.com/gpuweb/gpuweb/issues/1325

Bug: dawn:434
Change-Id: If63bd5fe9dccc1fff16a42cddf63e9d8265e65c5
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/37020
Commit-Queue: Austin Eng <enga@chromium.org>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Austin Eng <enga@chromium.org>

src/dawn_native/metal/BackendMTL.mm

diff --git a/src/dawn_native/metal/BackendMTL.mm b/src/dawn_native/metal/BackendMTL.mm
index ada2c6d..0637514 100644
--- a/src/dawn_native/metal/BackendMTL.mm
+++ b/src/dawn_native/metal/BackendMTL.mm
@@ -221,7 +221,10 @@
                 if ([*mDevice supportsFamily:MTLGPUFamilyMac2] ||
                     [*mDevice supportsFamily:MTLGPUFamilyApple5]) {
                     mSupportedExtensions.EnableExtension(Extension::PipelineStatisticsQuery);
-                    mSupportedExtensions.EnableExtension(Extension::TimestampQuery);
+
+                    // TODO(hao.x.li@intel.com): Not enable timestamp query here becuase it's not
+                    // clear how to convert timestamps to nanoseconds on Metal.
+                    // See https://github.com/gpuweb/gpuweb/issues/1325
                 }
             }