Fix NCU profiling under Buck PAR via KERNEL_PROFILER_PYTHON#137
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Summary: NCU profiling subprocesses failed inside a Buck PAR with: ``` ImportError: .../platform010/lib/python3.12/lib-dynload/_posixsubprocess.cpython-312-x86_64-linux-gnu.so: undefined symbol: _Py_NoneStruct ModuleNotFoundError: No module named 'torch' ``` Root cause: inside a PAR, sys.executable points at the static-linked native-main binary. Re-exec'ing it from a subprocess skips the env setup that bootstrap.sh performs (LD_LIBRARY_PATH for CUDA, LD_PRELOAD for the allocator, PYTHONPATH/FB_PAR* for the embedded import system), so the spawned Python falls back to system platform010 stdlib whose lib-dynload .so files are ABI-incompatible with the static libpython. Test Plan: Specify the right python executable for Buck PAR via "KERNEL_PROFILER_PYTHON"
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Summary:
NCU profiling subprocesses failed inside a Buck PAR with:
Root cause: inside a PAR, sys.executable points at the static-linked native-main binary. Re-exec'ing it from a subprocess skips the env setup that bootstrap.sh performs (LD_LIBRARY_PATH for CUDA, LD_PRELOAD for the allocator, PYTHONPATH/FB_PAR* for the embedded import system), so the spawned Python falls back to system platform010 stdlib whose lib-dynload .so files are ABI-incompatible with the static libpython.
Test Plan:
Specify the right python executable for Buck PAR via "KERNEL_PROFILER_PYTHON"