tools/perf/util/setup.py | 253 +++++++++++++++++++++++++-------------- 1 file changed, 166 insertions(+), 87 deletions(-)
Clean up and restructure the python setup script to resolve pylint
warnings, improve code quality, and increase robustness and
readability, targeting Python 3.9+ (the Linux kernel build minimum
Python version).
Changes:
- Restructure the script to use a `main()` function as the entry point,
leaving only imports, classes, and pure functions at module level.
- Eliminate all global/module-level variables, making them local to
`main()` or the respective classes/functions.
- Make `clang_has_option` a pure function by passing all necessary
parameters explicitly.
- Extract clang compiler flag filtering into a new
`filter_clang_options` helper function. This function uses a loop
over a tuple of options, replacing ~30 lines of repetitive blocks
and reducing branch/statement complexity in the main flow.
- Cleanly define attributes in `__init__` for `BuildExt` and `InstallLib`
and read environment variables dynamically within the methods, removing
their dependency on global variables.
- Replace legacy Popen with subprocess.run for safer process handling.
- Use list-based flag filtering (split, filter, re-join) instead of regex
`re.sub` substitutions on space-separated compiler flag strings. This
avoids boundary bugs and safely handles flags with arguments (e.g.
`-fcf-protection=full`).
- Safely parse `CC` env var using `shlex.split` to handle quotes and pass
compiler arguments as `list[str]` lists to helper functions, avoiding
redundant string formatting and parsing.
- Remove unused `import re`.
- Rename setuptools command subclasses to PascalCase (BuildExt, InstallLib).
- Add type annotations to functions and methods.
- Add missing docstrings for module, functions, and classes.
- Split long lines to adhere to standard limits.
Assisted-by: Antigravity:gemini-3.5-flash
Signed-off-by: Ian Rogers <irogers@google.com>
---
tools/perf/util/setup.py | 253 +++++++++++++++++++++++++--------------
1 file changed, 166 insertions(+), 87 deletions(-)
diff --git a/tools/perf/util/setup.py b/tools/perf/util/setup.py
index b65b1792ca05..55ff7d8cba7e 100644
--- a/tools/perf/util/setup.py
+++ b/tools/perf/util/setup.py
@@ -1,108 +1,187 @@
-from os import getenv, path
-from subprocess import Popen, PIPE
-from re import sub
+"""Setup script for perf python extension.
+
+This script is used to build and install the perf python binding.
+It handles compiler-specific flags, especially for clang, and configures
+the setuptools Extension.
+"""
+
+import os
import shlex
+import subprocess
+import sysconfig
-cc = getenv("CC")
-assert cc, "Environment variable CC not set"
+from setuptools import setup, Extension
+from setuptools.command.build_ext import build_ext as _build_ext
+from setuptools.command.install_lib import install_lib as _install_lib
-# Check if CC has options, as is the case in yocto, where it uses CC="cc --sysroot..."
-cc_tokens = cc.split()
-if len(cc_tokens) > 1:
- cc = cc_tokens[0]
- cc_options = " ".join([str(e) for e in cc_tokens[1:]]) + " "
-else:
- cc_options = ""
-# ignore optional stderr could be None as it is set to PIPE to avoid that.
-# mypy: disable-error-code="union-attr"
-cc_is_clang = b"clang version" in Popen([cc, "-v"], stderr=PIPE).stderr.readline()
+def clang_has_option(cc: str, cc_args: list[str], src_feature_tests: str, option: str) -> bool:
+ """Check if clang supports a specific option.
-srctree = getenv('srctree')
-assert srctree, "Environment variable srctree, for the Linux sources, not set"
-src_feature_tests = f'{srctree}/tools/build/feature'
+ Args:
+ cc: The compiler executable.
+ cc_args: Compiler arguments from CC environment variable.
+ src_feature_tests: Path to the feature tests directory.
+ option: The compiler option to check (e.g., "-mcet").
-def clang_has_option(option):
+ Returns:
+ True if the option is supported, False otherwise.
+ """
error_substrings = (
b"unknown argument",
b"is not supported",
b"unknown warning option"
)
- cmd = shlex.split(f"{cc} {cc_options} {option}") + [
+ cmd = [cc] + cc_args + [
+ option,
"-o", "/dev/null",
- path.join(src_feature_tests, "test-hello.c")
+ os.path.join(src_feature_tests, "test-hello.c")
]
- cc_output = Popen(cmd, stderr=PIPE).stderr.readlines()
+ try:
+ res = subprocess.run(cmd, stderr=subprocess.PIPE, stdout=subprocess.DEVNULL, check=False)
+ cc_output = res.stderr.splitlines()
+ except OSError:
+ return False
return not any(any(error in line for error in error_substrings) for line in cc_output)
-if cc_is_clang:
- from sysconfig import get_config_vars
- vars = get_config_vars()
+
+def filter_clang_options(cc: str, cc_args: list[str], src_feature_tests: str) -> None:
+ """Filter out unsupported clang options from sysconfig CFLAGS and OPT.
+
+ Args:
+ cc: The compiler executable.
+ cc_args: Compiler arguments from CC environment variable.
+ src_feature_tests: Path to the feature tests directory.
+ """
+ config_vars = sysconfig.get_config_vars()
for var in ('CFLAGS', 'OPT'):
- vars[var] = sub("-specs=[^ ]+", "", vars[var])
- if not clang_has_option("-mcet"):
- vars[var] = sub("-mcet", "", vars[var])
- if not clang_has_option("-fcf-protection"):
- vars[var] = sub("-fcf-protection", "", vars[var])
- if not clang_has_option("-fstack-clash-protection"):
- vars[var] = sub("-fstack-clash-protection", "", vars[var])
- if not clang_has_option("-fstack-protector-strong"):
- vars[var] = sub("-fstack-protector-strong", "", vars[var])
- if not clang_has_option("-fno-semantic-interposition"):
- vars[var] = sub("-fno-semantic-interposition", "", vars[var])
- if not clang_has_option("-ffat-lto-objects"):
- vars[var] = sub("-ffat-lto-objects", "", vars[var])
- if not clang_has_option("-ftree-loop-distribute-patterns"):
- vars[var] = sub("-ftree-loop-distribute-patterns", "", vars[var])
- if not clang_has_option("-gno-variable-location-views"):
- vars[var] = sub("-gno-variable-location-views", "", vars[var])
+ if var not in config_vars:
+ continue
+
+ # Split into individual flags to avoid regex boundary issues
+ flags = config_vars[var].split()
+
+ # Remove -specs=...
+ flags = [f for f in flags if not f.startswith("-specs=")]
+
+ options = (
+ "-mcet",
+ "-fcf-protection",
+ "-fstack-clash-protection",
+ "-fstack-protector-strong",
+ "-fno-semantic-interposition",
+ "-ffat-lto-objects",
+ "-ftree-loop-distribute-patterns",
+ "-gno-variable-location-views"
+ )
+ for option in options:
+ if not clang_has_option(cc, cc_args, src_feature_tests, option):
+ # Remove the option and any variant (e.g. -option=...)
+ flags = [f for f in flags if not f.startswith(option)]
+
+ # Re-join flags
+ config_vars[var] = " ".join(flags)
+
+
+class BuildExt(_build_ext):
+ """Custom build_ext command to set output directories."""
+
+ def __init__(self, *args, **kwargs):
+ self.build_lib = None
+ self.build_temp = None
+ super().__init__(*args, **kwargs)
+
+ def finalize_options(self) -> None:
+ _build_ext.finalize_options(self)
+ build_lib = os.getenv('PYTHON_EXTBUILD_LIB')
+ build_tmp = os.getenv('PYTHON_EXTBUILD_TMP')
+ if build_lib:
+ self.build_lib = build_lib
+ if build_tmp:
+ self.build_temp = build_tmp
-from setuptools import setup, Extension
-from setuptools.command.build_ext import build_ext as _build_ext
-from setuptools.command.install_lib import install_lib as _install_lib
+class InstallLib(_install_lib):
+ """Custom install_lib command to set output directory."""
-class build_ext(_build_ext):
- def finalize_options(self):
- _build_ext.finalize_options(self)
- self.build_lib = build_lib
- self.build_temp = build_tmp
+ def __init__(self, *args, **kwargs):
+ self.build_dir = None
+ super().__init__(*args, **kwargs)
-class install_lib(_install_lib):
- def finalize_options(self):
+ def finalize_options(self) -> None:
_install_lib.finalize_options(self)
- self.build_dir = build_lib
-
-
-cflags = getenv('CFLAGS', '').split()
-# switch off several checks (need to be at the end of cflags list)
-cflags += ['-fno-strict-aliasing', '-Wno-write-strings', '-Wno-unused-parameter', '-Wno-redundant-decls' ]
-if cc_is_clang:
- cflags += ["-Wno-unused-command-line-argument" ]
- if clang_has_option("-Wno-cast-function-type-mismatch"):
- cflags += ["-Wno-cast-function-type-mismatch" ]
-else:
- cflags += ['-Wno-cast-function-type' ]
-
-# The python headers have mixed code with declarations (decls after asserts, for instance)
-cflags += [ "-Wno-declaration-after-statement" ]
-
-src_perf = f'{srctree}/tools/perf'
-build_lib = getenv('PYTHON_EXTBUILD_LIB')
-build_tmp = getenv('PYTHON_EXTBUILD_TMP')
-
-perf = Extension('perf',
- sources = [ src_perf + '/util/python.c' ],
- include_dirs = ['util/include'],
- extra_compile_args = cflags,
- )
-
-setup(name='perf',
- version='0.1',
- description='Interface with the Linux profiling infrastructure',
- author='Arnaldo Carvalho de Melo',
- author_email='acme@redhat.com',
- license='GPLv2',
- url='http://perf.wiki.kernel.org',
- ext_modules=[perf],
- cmdclass={'build_ext': build_ext, 'install_lib': install_lib})
+ build_lib = os.getenv('PYTHON_EXTBUILD_LIB')
+ if build_lib:
+ self.build_dir = build_lib
+
+
+def main() -> None:
+ """Main entry point for the setup script."""
+ cc_env = os.getenv("CC")
+ assert cc_env, "Environment variable CC not set"
+
+ # Safe parsing of CC environment variable which might contain options/quotes
+ cc_tokens = shlex.split(cc_env)
+ cc = cc_tokens[0]
+ cc_args = cc_tokens[1:]
+
+ # Run CC -v to check if it is clang.
+ try:
+ cc_info = subprocess.run(
+ [cc, "-v"], stderr=subprocess.PIPE, stdout=subprocess.DEVNULL, check=False
+ )
+ cc_is_clang = b"clang version" in cc_info.stderr
+ except OSError as e:
+ raise RuntimeError(f"Failed to execute compiler '{cc}': {e}") from e
+
+ srctree = os.getenv('srctree')
+ assert srctree, "Environment variable srctree, for the Linux sources, not set"
+ src_feature_tests = f'{srctree}/tools/build/feature'
+
+ if cc_is_clang:
+ filter_clang_options(cc, cc_args, src_feature_tests)
+
+ cflags = os.getenv('CFLAGS', '').split()
+ # switch off several checks (need to be at the end of cflags list)
+ cflags += [
+ '-fno-strict-aliasing',
+ '-Wno-write-strings',
+ '-Wno-unused-parameter',
+ '-Wno-redundant-decls'
+ ]
+ if cc_is_clang:
+ cflags += ["-Wno-unused-command-line-argument"]
+ if clang_has_option(
+ cc, cc_args, src_feature_tests, "-Wno-cast-function-type-mismatch"
+ ):
+ cflags += ["-Wno-cast-function-type-mismatch"]
+ else:
+ cflags += ['-Wno-cast-function-type']
+
+ # The python headers have mixed code with declarations (decls after asserts, for instance)
+ cflags += ["-Wno-declaration-after-statement"]
+
+ src_perf = f'{srctree}/tools/perf'
+
+ perf = Extension(
+ 'perf',
+ sources=[os.path.join(src_perf, 'util/python.c')],
+ include_dirs=['util/include'],
+ extra_compile_args=cflags,
+ )
+
+ setup(
+ name='perf',
+ version='0.1',
+ description='Interface with the Linux profiling infrastructure',
+ author='Arnaldo Carvalho de Melo',
+ author_email='acme@redhat.com',
+ license='GPLv2',
+ url='http://perf.wiki.kernel.org',
+ ext_modules=[perf],
+ cmdclass={'build_ext': BuildExt, 'install_lib': InstallLib},
+ )
+
+
+if __name__ == '__main__':
+ main()
--
2.54.0.794.g4f17f83d09-goog© 2016 - 2026 Red Hat, Inc.