Add option to control fetching L0

[igchor]

Turning UMF_BUILD_LEVEL_ZERO_PROVIDER on in UR
results in configuration errors as both projects try to fetch and build L0 loader.

• Code compiles without errors locally
• All tests pass locally
• CI workflows execute properly

[bratpiorka]

@igchor is this needed for 2025.0? AFAIK UR would not use L0 provider from UMF in 2025.0?

[igchor]

@igchor is this needed for 2025.0? AFAIK UR would not use L0 provider from UMF in 2025.0?

No, it's not for 2025.0. I'm working on L0 v2 adapter (https://github.com/oneapi-src/unified-runtime/tree/main/source/adapters/level_zero/v2) and I'd rather use UMF instead of duplicating the original logic for USM. We would still need to implement missing features (at least support for making the memory resident) but that shouldn't be too difficult.

[igchor]

@bratpiorka @lukaszstolarczuk Ok, I did it slightly differently. Since we only need loader for tests (and example, but they have separate fetch_content) we can just add option to set UMF_LEVEL_ZERO_INCLUDE_DIR. If this option is set and we don't need the loader, we can skip fetching L0. UR actually have a similar mechanism with UR_LEVEL_ZERO_INCLUDE_DIR

[igchor]

@lukaszstolarczuk do you know why the GPU tests are failing on CI? it works for me locally

[lukaszstolarczuk]

@lukaszstolarczuk do you know why the GPU tests are failing on CI? it works for me locally

I think it's the issue with the machine, it should be fixed by now. I've hit re-run.

[igchor]

@bratpiorka @lukaszstolarczuk are you OK with this solution? I've made a draft PR to UR to test this: oneapi-src/unified-runtime#2012