[cuda] Fix deadlock when advancing deferred queue in driver thread (#15673)

When GPU signals the CUevent-implemented semaphore to a new value, we
need to perform a `cuLaunchHostFunc()` to invoke the CPU to signal to
that value. At the same time, we can try to advance the deferred queue
to release more workload to the GPU. Advancing the deferred queue cannot
happen as part of the `cuLaunchHostFunc()` call, given that is in a
driver thread. Per the documentation:

  The host function must not make any CUDA API calls. Attempting
  to use a CUDA API may result in CUDA_ERROR_NOT_PERMITTED, but
  this is not required. The host function must not perform any
  synchronization that may depend on outstanding CUDA work not
  mandated to run earlier. Host functions without a mandated order
  (such as in independent streams) execute in undefined order and
  may be serialized.

We were actually doing that and seeing deadlock. So this commit changes
the implemention to create a new thread dedicated to monitoring and
releasing workload to the GPU, to avoid calling CUDA APIs as part of the
`cuLaunchHostFunc()` call.

Progress towards https://github.com/openxla/iree/issues/13245
4 files changed
tree: 0d7a14feaebece372edb067b33a1a90629d76f69
  1. .devcontainer/
  2. .github/
  3. build_tools/
  4. compiler/
  5. docs/
  6. experimental/
  7. integrations/
  8. lib/
  9. llvm-external-projects/
  10. runtime/
  11. samples/
  12. tests/
  13. third_party/
  14. tools/
  15. .bazel_to_cmake.cfg.py
  16. .bazelignore
  17. .bazelrc
  18. .bazelversion
  19. .clang-format
  20. .dockerignore
  21. .git-blame-ignore-revs
  22. .gitignore
  23. .gitmodules
  24. .yamllint.yml
  25. AUTHORS
  26. BUILD.bazel
  27. CITATION.cff
  28. CMakeLists.txt
  29. configure_bazel.py
  30. CONTRIBUTING.md
  31. LICENSE
  32. README.md
  33. WORKSPACE
README.md

IREE: Intermediate Representation Execution Environment

IREE (Intermediate Representation Execution Environment, pronounced as “eerie”) is an MLIR-based end-to-end compiler and runtime that lowers Machine Learning (ML) models to a unified IR that scales up to meet the needs of the datacenter and down to satisfy the constraints and special considerations of mobile and edge deployments.

See our website for project details, user guides, and instructions on building from source.

CI Status

Project Status

IREE is still in its early phase. We have settled down on the overarching infrastructure and are actively improving various software components as well as project logistics. It is still quite far from ready for everyday use and is made available without any support at the moment. With that said, we welcome any kind of feedback on any communication channels!

Communication Channels

Related Project Channels

  • MLIR topic within LLVM Discourse: IREE is enabled by and heavily relies on MLIR. IREE sometimes is referred to in certain MLIR discussions. Useful if you are also interested in MLIR evolution.

Architecture Overview

IREE Architecture IREE Architecture

See our website for more information.

Presentations and Talks

License

IREE is licensed under the terms of the Apache 2.0 License with LLVM Exceptions. See LICENSE for more information.