[Openmp-commits] [PATCH] D144975: [OpenMP][libomptarget][NFC] Add documentation regarding NextGen plugins

Mon Mar 13 08:43:38 PDT 2023

kevinsala added inline comments.

================
Comment at: openmp/docs/design/Runtimes.rst:1244
+streams. More HSA signals will be created dynamically throughout the execution
+if needed. The default value is ``64``.
+
----------------
jplehr wrote:
> kevinsala wrote:
> > jdoerfert wrote:
> > > Is this separate from the other SIGNALS env var on purpose? We can discuss this in our meeting.
> > Which SIGNALS envars are you referring to?
> > 
> > There are the other two `LIBOMPTARGET_NUM_INITIAL_STREAMS` and `LIBOMPTARGET_NUM_INITIAL_EVENTS` envars. But these two are different since these two apply to all plugins and `LIBOMPTARGET_AMDGPU_NUM_INITIAL_HSA_SIGNALS` only applies to AMDGPU.
> Is there a specific reason why more `HSA_SIGNALS` are created initially than `EVENTS`?
There is no specific reason. I did set that value at the beginning and didn't try if there are better ones. Maybe someone else tried other values, but I'm not aware of that.

Anyhow, the use of events/streams is slightly different than the HSA signals. The first two are exposed to libomptarget, whereas the HSA signals are resources used by the AMDGPU plugin internally.

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D144975/new/

https://reviews.llvm.org/D144975