[SYCL] [L0] Use L0 immediate commandlists if specified via env var. #6468
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Signed-off-by: Rajiv Deodhar <[email protected]>
| // For some devices (e.g. PVC) immediate commandlists are preferred. | ||
| bool ImmCommandListsPreferred; | ||
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| // Return the Events scope to be used in for this device. |
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Can that be a problem that the 2+ devices in the system use different event scopes? Say, one device is submitting immediately and as such is using the OnDemandHostVisibleProxy and the other device is waiting for it (not involving host, otherwise a host-visible proxy would be created and waited. Is there no possibility of deadlock here?
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L0 distinguishes between host-visible or not. When not host visible the documentation says that events are visible to peer devices.
This issue (if an issue) is not unique to use of immediate commandlists. If the plugin is set to use OnDemandHostVisibleProxy then the same situation of cross-device event checking could still occur.
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With the OnDemandHostVisibleProxy, the proxy is only created when SYCL RT is waiting for an event on the host. Until these changes every device would use the same strategy, so there wouldn't be a conflict (in strategies). Could you try to create a test case that different devices (now using the different strategies) would still work together smoothly?
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A test for cross-device events has been created and is being used to verify the situation where one device might use standard commandlists and another immediate commandlists.
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I assume the test didn't reveal any issues currently, right?
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No issues found by the test - cross-device events work as expected.
rdeodhar
changed the title
Use L0 immediate commandlists if explicitly specified.
This is a preliminary step towards using deviceid to detect devices on which use of immediate commandlists is preferred, and switching to using immediate commandlists on those devices automatically.
Signed-off-by: Rajiv Deodhar [email protected]