[llvm] [llvm-exegesis] Add support for pinning benchmarking process to a CPU (PR #85168)

Thu Sep 19 06:41:20 PDT 2024

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `ppc64le-flang-rhel-clang` running on `ppc64le-flang-rhel-test` while building `llvm` at step 5 "build-unified-tree".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/157/builds/8166

<details>
<summary>Here is the relevant piece of the build log for the reference</summary>

```
Step 5 (build-unified-tree) failure: build (failure)
...
80.614 [215/35/6310] Linking CXX static library lib/libLLVMOrcDebugging.a
80.627 [214/35/6311] Linking CXX static library lib/libclangToolingInclusions.a
80.633 [213/35/6312] Linking CXX executable bin/f18-parse-demo
80.905 [213/34/6313] Linking CXX static library lib/libclangAnalysis.a
80.946 [211/35/6314] Linking CXX executable bin/apinotes-test
80.949 [211/34/6315] Linking CXX static library lib/libclangFormat.a
80.956 [210/34/6316] Linking CXX static library lib/libMLIRNVVMTarget.a
80.958 [210/33/6317] Linking CXX static library lib/libclangDynamicASTMatchers.a
80.980 [210/32/6318] Linking CXX static library lib/libMLIRROCDLTarget.a
81.071 [209/32/6319] Building CXX object tools/llvm-exegesis/lib/CMakeFiles/LLVMExegesis.dir/BenchmarkRunner.cpp.o
FAILED: tools/llvm-exegesis/lib/CMakeFiles/LLVMExegesis.dir/BenchmarkRunner.cpp.o 
ccache /home/buildbots/llvm-external-buildbots/clang.16.0.1/bin/clang++ -DGTEST_HAS_RTTI=0 -DLLVM_BUILD_STATIC -D_DEBUG -D_GLIBCXX_ASSERTIONS -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-flang-rhel-test/ppc64le-flang-rhel-clang-build/build/tools/llvm-exegesis/lib -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-flang-rhel-test/ppc64le-flang-rhel-clang-build/llvm-project/llvm/tools/llvm-exegesis/lib -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-flang-rhel-test/ppc64le-flang-rhel-clang-build/build/include -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-flang-rhel-test/ppc64le-flang-rhel-clang-build/llvm-project/llvm/include -fPIC -fno-semantic-interposition -fvisibility-inlines-hidden -Werror=date-time -Werror=unguarded-availability-new -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -pedantic -Wno-long-long -Wc++98-compat-extra-semi -Wimplicit-fallthrough -Wcovered-switch-default -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wsuggest-override -Wstring-conversion -Wmisleading-indentation -Wctad-maybe-unsupported -fdiagnostics-color -ffunction-sections -fdata-sections -O3 -DNDEBUG -std=c++17  -fno-exceptions -funwind-tables -fno-rtti -UNDEBUG -MD -MT tools/llvm-exegesis/lib/CMakeFiles/LLVMExegesis.dir/BenchmarkRunner.cpp.o -MF tools/llvm-exegesis/lib/CMakeFiles/LLVMExegesis.dir/BenchmarkRunner.cpp.o.d -o tools/llvm-exegesis/lib/CMakeFiles/LLVMExegesis.dir/BenchmarkRunner.cpp.o -c /home/buildbots/llvm-external-buildbots/workers/ppc64le-flang-rhel-test/ppc64le-flang-rhel-clang-build/llvm-project/llvm/tools/llvm-exegesis/lib/BenchmarkRunner.cpp
/home/buildbots/llvm-external-buildbots/workers/ppc64le-flang-rhel-test/ppc64le-flang-rhel-clang-build/llvm-project/llvm/tools/llvm-exegesis/lib/BenchmarkRunner.cpp:411:12: error: use of undeclared identifier 'getcpu'; did you mean 'getcwd'?
    assert(getcpu(&CurrentCPU, nullptr) == 0 &&
           ^~~~~~
           getcwd
/usr/include/assert.h:90:27: note: expanded from macro 'assert'
     (static_cast <bool> (expr)                                         \
                          ^
/usr/include/unistd.h:511:14: note: 'getcwd' declared here
extern char *getcwd (char *__buf, size_t __size) __THROW __wur;
             ^
/home/buildbots/llvm-external-buildbots/workers/ppc64le-flang-rhel-test/ppc64le-flang-rhel-clang-build/llvm-project/llvm/tools/llvm-exegesis/lib/BenchmarkRunner.cpp:411:19: error: cannot initialize a parameter of type 'char *' with an rvalue of type 'unsigned int *'
    assert(getcpu(&CurrentCPU, nullptr) == 0 &&
                  ^~~~~~~~~~~
/usr/include/assert.h:90:27: note: expanded from macro 'assert'
     (static_cast <bool> (expr)                                         \
                          ^~~~
/usr/include/unistd.h:511:28: note: passing argument to parameter '__buf' here
extern char *getcwd (char *__buf, size_t __size) __THROW __wur;
                           ^
2 errors generated.
81.174 [209/31/6320] Linking CXX executable bin/llvm-cgdata
81.213 [209/30/6321] Linking CXX static library lib/libclangAnalysisFlowSensitive.a
81.364 [209/29/6322] Linking CXX static library lib/libMLIRGPUTransforms.a
81.438 [209/28/6323] Linking CXX executable tools/flang/unittests/Evaluate/integer.test
81.474 [209/27/6324] Linking CXX static library lib/libclangSema.a
81.557 [209/26/6325] Linking CXX executable tools/flang/unittests/Evaluate/logical.test
81.861 [209/25/6326] Linking CXX executable bin/lli-child-target
81.907 [209/24/6327] Linking CXX executable tools/flang/unittests/Evaluate/real.test
82.271 [209/23/6328] Building CXX object tools/llvm-exegesis/lib/PowerPC/CMakeFiles/LLVMExegesisPowerPC.dir/Target.cpp.o
82.402 [209/22/6329] Linking CXX executable bin/llvm-link
82.421 [209/21/6330] Linking CXX executable bin/clang-offload-bundler
82.635 [209/20/6331] Linking CXX executable bin/clang-format
82.772 [209/19/6332] Linking CXX executable bin/llvm-profgen
82.858 [209/18/6333] Linking CXX executable tools/flang/unittests/Evaluate/expression.test
82.995 [209/17/6334] Linking CXX executable tools/flang/unittests/Evaluate/folding.test
83.499 [209/16/6335] Building CXX object tools/llvm-exegesis/lib/CMakeFiles/LLVMExegesis.dir/ParallelSnippetGenerator.cpp.o
83.719 [209/15/6336] Linking CXX executable bin/llvm-jitlink

```

</details>

https://github.com/llvm/llvm-project/pull/85168