Ross Brunton 910d7e90bf
[Offload] Make olLaunchKernel test thread safe (#149497)
This sprinkles a few mutexes around the plugin interface so that the
olLaunchKernel CTS test now passes when ran on multiple threads.

Part of this also involved changing the interface for device synchronise
so that it can optionally not free the underlying queue (which
introduced a race condition in liboffload).
2025-08-08 10:57:04 +01:00
..

Liboffload

This directory contains the implementation of the work-in-progress new API for Offload. It builds on top of the existing plugin implementations but provides a single level of abstraction suitable for implementation of many offloading language runtimes, rather than just OpenMP.

Testing liboffload

The main test suite for liboffload can be run with the check-offload-unit target, which runs the offload.unittests executable. The test suite will automatically run on every available device, but can be restricted to a single platform (CUDA, AMDGPU) with a command line argument:

$ ./offload.unittests --platform=CUDA

Tracing of Offload API calls can be enabled by setting the OFFLOAD_TRACE environment variable. This works with any program that uses liboffload.

$ OFFLOAD_TRACE=1 ./offload.unittests
---> olInit()-> OL_SUCCESS
# etc

The host plugin is not currently supported.

Modifying liboffload

The main header (OffloadAPI.h) and some implementation details are autogenerated with tablegen. See the API definition README for implementation details.