[Openmp-commits] [PATCH] D94256: [OpenMP] Fixed the issue that memory manager calls plugin interface to release buffered memory even after the plugin has been destroyed

[Shilei Tian via Phabricator via Openmp-commits]

tianshilei1992 created this revision.
tianshilei1992 added reviewers: jdoerfert, JonChesterfield, manorom, protze.joachim.
Herald added subscribers: guansong, yaxunl.
tianshilei1992 requested review of this revision.
Herald added subscribers: openmp-commits, sstefan1.
Herald added a project: OpenMP.

Currently on some platforms the program might crash when the program
exits. It is because the memory manager calls plugin interface to release its
buffered memory and the plugin has already been destroyed. After some search
online, it seems that loaded dynamic libraries will be destroyed in the reverse
order of loading, which means by no means, those plugin libraries loaded by
`dlopen` will be destroyed before `libomtarget`. We need something to tell the
`RTLInfoTy` that the hold plugin is not valid anymore so don't call those
interfaces. This is done by registering a callback function in the plugin so that
it will be called when the plugin starts to destroy itself. The callback function
for now only does one thing: invalidate the `RTLInfoTy`. We can add more features
in the future if needed. For now we only check the validity when invoking
`data_delete`. Not sure whether need to do the check for every use. The check is
wrapped into a macro `UNLIKELY` to tell the compiler this branch is unlikely to
be taken to hopefully optimize the performance.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D94256

Files:
  openmp/libomptarget/include/omptargetplugin.h
  openmp/libomptarget/plugins/cuda/src/rtl.cpp
  openmp/libomptarget/plugins/exports
  openmp/libomptarget/src/MemoryManager.cpp
  openmp/libomptarget/src/rtl.cpp
  openmp/libomptarget/src/rtl.h

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