Summary: As above, also changes a bunch of the build files to be better
Test Plan:
internal and external CI
did run buck2 build fbcode//caffe2:torch and it succeeded
Rollback Plan:
Reviewed By: swolchok
Differential Revision: D78016591
Pull Request resolved: https://github.com/pytorch/pytorch/pull/158035
Approved by: https://github.com/swolchok
# Motivation
As mentioned in [[RFC] Intel GPU Runtime Upstreaming](https://github.com/pytorch/pytorch/issues/114842), The first runtime component we would like to upstream is `Device` which contains the device management functions of Intel GPU's runtime. To facilitate the code review, we split the code changes into 4 PRs. This is one of the 4 PRs and covers the changes under `c10`.
# Design
Intel GPU device is a wrapper of sycl device on which kernels can be executed. In our design, we will maintain a sycl device pool containing all the GPU devices of the current machine, and manage the status of the device pool by PyTorch. The thread local safe is considered in this design. The corresponding C++ files related to `Device` will be placed in c10/xpu folder. And we provide the c10 device runtime APIs, like
- `c10::xpu::device_count`
- `c10::xpu::set_device`
- ...
# Additional Context
In our plan, 4 PRs should be submitted to PyTorch for `Device`:
1. for c10
2. for aten
3. for python frontend
4. for lazy initialization shared with CUDA
Pull Request resolved: https://github.com/pytorch/pytorch/pull/116019
Approved by: https://github.com/gujinghui, https://github.com/jgong5, https://github.com/EikanWang, https://github.com/malfet
`libshm.so` depends on the torch library exclusively for `at::RefcountedMapAllocator`,
so it makes sense to move it to c10 along with the other memory allocators.
This means `libshm.so` only depends on `c10` and we don't need to relink
`libshm.so` for every ATen change.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/109881
Approved by: https://github.com/albanD