[UR][L0] Fix Implict Event sync during external semaphore wait/signal #19859
Conversation
nrspruit
commented
Aug 22, 2025
nrspruit
commented
- When SYCl Calls the L0 adapter without a signal event, L0 creates an internal event.
- Given in order command queue, the internal event for the wait/signal is implicitly added to the wait list of the next command if executeCommandList is called.
- This ensures that the internal event is properly synchronized with the command queue during that next call given SYCL is failing to create a UR event for tracking the wait/signal.
- When SYCl Calls the L0 adapter without a signal event, L0 creates an internal event. - Given in order command queue, the internal event for the wait/signal is implicitly added to the wait list of the next command if executeCommandList is called. - This ensures that the internal event is properly synchronized with the command queue during that next call given SYCL is failing to create a UR event for tracking the wait/signal. Signed-off-by: Neil R. Spruit <neil.r.spruit@intel.com>
|
Are there any unit or conformance tests that test the issue this PR fixes? |
https://github.com/intel/llvm/blob/sycl/sycl/test-e2e/bindless_images/vulkan_interop/unsampled_images.cpp will reproduce the issue, however only sporadically so that means a new CTS is needed to validate the sycl side does not get executed before the Vulkan dependency is executed. |
|
it should be noted, that while this is needed to fix the issue for L0 indirect internal events, the root bug is that external semaphores in sycl are not implemented properly. |
|
@intel/bindless-images-reviewers , please review, this addresses the missing support for internal events given external semaphore. I will be working on adding a CTS to cover this gap in another review, but adding that CTS will result in new failures since the larger bug is in the SYCL layer itself. |
