Normal behavior of ApiObjectBase's APIRelease() which only locks the
device when last ref dropped is not thread safe if the object is cached
as raw pointers by the device. Example of cached objects: bind group
layout, pipeline, sampler, shader module.
The following scenario could happen:
- thread A:
- shaderModuleA.APIRealease()
- shaderModuleA.refCount.Decrement() == true (ref count has reached zero)
- going to call shaderModuleA.LockAndDeleteThis().
- thread B:
- device.CreateShaderModule().
- lock()
- device.GetOrCreateShaderModule()
- shaderModuleA is in the cache, so return it.
- unlock()
- thread A:
- starting to call shaderModuleA.LockAndDeleteThis()
- lock()
- erase shaderModuleA from the cache.
- delete shaderModuleA.
- unlock()
This CL disables caching when ImplicitDeviceSynchronization is turned on
until we find a better solution.
Bug: dawn:1769
Change-Id: Ideb2a717ece0a40e18bd1c2bef00817262bd25da
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/127900
Commit-Queue: Quyen Le <lehoangquyen@chromium.org>
Reviewed-by: Austin Eng <enga@chromium.org>
Kokoro: Kokoro <noreply+kokoro@google.com>
Le Hoang Quyen