perf build: Add pylint build tests

If PYLINT=1 is passed to the build then run pylint over python code in
perf. Unlike shellcheck this isn't default on as there are currently
too many errors.

An example of an error:
```
************* Module setup
util/setup.py:19:0: C0301: Line too long (127/100) (line-too-long)
util/setup.py:20:0: C0301: Line too long (138/100) (line-too-long)
util/setup.py:63:0: C0301: Line too long (106/100) (line-too-long)
util/setup.py:1:0: C0114: Missing module docstring (missing-module-docstring)
util/setup.py:24:4: W0622: Redefining built-in 'vars' (redefined-builtin)
util/setup.py:11:4: C0103: Constant name "cc_options" doesn't conform to UPPER_CASE naming style (invalid-name)
util/setup.py:13:4: C0103: Constant name "cc_options" doesn't conform to UPPER_CASE naming style (invalid-name)
util/setup.py:15:34: R1732: Consider using 'with' for resource-allocating operations (consider-using-with)
util/setup.py:18:0: C0116: Missing function or method docstring (missing-function-docstring)
util/setup.py:19:16: R1732: Consider using 'with' for resource-allocating operations (consider-using-with)
util/setup.py:44:0: C0413: Import "from setuptools import setup, Extension" should be placed at the top of the module (wrong-import-position)
util/setup.py:46:0: C0413: Import "from setuptools.command.build_ext import build_ext as _build_ext" should be placed at the top of the module (wrong-import-position)
util/setup.py:47:0: C0413: Import "from setuptools.command.install_lib import install_lib as _install_lib" should be placed at the top of the module (wrong-import-position)
util/setup.py:49:0: C0115: Missing class docstring (missing-class-docstring)
util/setup.py:49:0: C0103: Class name "build_ext" doesn't conform to PascalCase naming style (invalid-name)
util/setup.py:52:8: W0201: Attribute 'build_lib' defined outside __init__ (attribute-defined-outside-init)
util/setup.py:53:8: W0201: Attribute 'build_temp' defined outside __init__ (attribute-defined-outside-init)
util/setup.py:55:0: C0115: Missing class docstring (missing-class-docstring)
util/setup.py:55:0: C0103: Class name "install_lib" doesn't conform to PascalCase naming style (invalid-name)
util/setup.py:58:8: W0201: Attribute 'build_dir' defined outside __init__ (attribute-defined-outside-init)

*-----------------------------------------------------------------
Your code has been rated at 6.67/10 (previous run: 6.51/10, +0.16)

make[4]: *** [util/Build:442: util/setup.py.pylint_log] Error 1
```

Reviewed-by: James Clark <james.clark@linaro.org>
Signed-off-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/20250311213628.569562-5-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>

tools/perf/Build

@@ -89,3 +89,16 @@ $(OUTPUT)%.mypy_log: %
 	$(Q)$(call echo-cmd,test)mypy "$<" > $@ || (cat $@ && rm $@ && false)
 
 perf-y += $(MYPY_TEST_LOGS)
+
+ifdef PYLINT
+  PY_TESTS := $(shell find python -type f -name '*.py')
+  PYLINT_TEST_LOGS := $(PY_TESTS:python/%=python/%.pylint_log)
+else
+  PYLINT_TEST_LOGS :=
+endif
+
+$(OUTPUT)%.pylint_log: %
+	$(call rule_mkdir)
+	$(Q)$(call echo-cmd,test)pylint "$<" > $@ || (cat $@ && rm $@ && false)
+
+perf-y += $(PYLINT_TEST_LOGS)

tools/perf/Makefile.perf

@@ -311,8 +311,13 @@ ifeq ($(MYPY),1)
   MYPY := $(shell which mypy 2> /dev/null)
 endif
 
+# Runs pylint on perf python files
+ifeq ($(PYLINT),1)
+  PYLINT := $(shell which pylint 2> /dev/null)
+endif
+
 export srctree OUTPUT RM CC CXX LD AR CFLAGS CXXFLAGS V BISON FLEX AWK
-export HOSTCC HOSTLD HOSTAR HOSTCFLAGS SHELLCHECK MYPY
+export HOSTCC HOSTLD HOSTAR HOSTCFLAGS SHELLCHECK MYPY PYLINT
 
 include $(srctree)/tools/build/Makefile.include
 

tools/perf/pmu-events/Build

@@ -52,8 +52,19 @@ $(OUTPUT)%.mypy_log: %
 	$(call rule_mkdir)
 	$(Q)$(call echo-cmd,test)mypy "$<" > $@ || (cat $@ && rm $@ && false)
 
+ifdef PYLINT
+  PMU_EVENTS_PY_TESTS := $(wildcard *.py)
+  PMU_EVENTS_PYLINT_TEST_LOGS := $(JEVENTS_PY_TESTS:%=%.pylint_log)
+else
+  PMU_EVENTS_PYLINT_TEST_LOGS :=
+endif
+
+$(OUTPUT)%.pylint_log: %
+	$(call rule_mkdir)
+	$(Q)$(call echo-cmd,test)pylint "$<" > $@ || (cat $@ && rm $@ && false)
+
 $(PMU_EVENTS_C): $(JSON) $(JSON_TEST) $(JEVENTS_PY) $(METRIC_PY) $(METRIC_TEST_LOG) \
-    $(EMPTY_PMU_EVENTS_TEST_LOG) $(PMU_EVENTS_MYPY_TEST_LOGS)
+    $(EMPTY_PMU_EVENTS_TEST_LOG) $(PMU_EVENTS_MYPY_TEST_LOGS) $(PMU_EVENTS_PYLINT_TEST_LOGS)
 	$(call rule_mkdir)
 	$(Q)$(call echo-cmd,gen)$(PYTHON) $(JEVENTS_PY) $(JEVENTS_ARCH) $(JEVENTS_MODEL) pmu-events/arch $@
 endif

tools/perf/scripts/Build

@@ -15,3 +15,16 @@ $(OUTPUT)%.mypy_log: %
 	$(Q)$(call echo-cmd,test)mypy "$<" > $@ || (cat $@ && rm $@ && false)
 
 perf-y += $(MYPY_TEST_LOGS)
+
+ifdef PYLINT
+  PY_TESTS := $(shell find python -type f -name '*.py')
+  PYLINT_TEST_LOGS := $(PY_TESTS:python/%=python/%.pylint_log)
+else
+  PYLINT_TEST_LOGS :=
+endif
+
+$(OUTPUT)%.pylint_log: %
+	$(call rule_mkdir)
+	$(Q)$(call echo-cmd,test)pylint "$<" > $@ || (cat $@ && rm $@ && false)
+
+perf-y += $(PYLINT_TEST_LOGS)

tools/perf/tests/Build

@@ -104,3 +104,16 @@ $(OUTPUT)%.mypy_log: %
 	$(Q)$(call echo-cmd,test)mypy "$<" > $@ || (cat $@ && rm $@ && false)
 
 perf-test-y += $(MYPY_TEST_LOGS)
+
+ifdef PYLINT
+  PY_TESTS := $(shell find tests/shell -type f -name '*.py')
+  PYLINT_TEST_LOGS := $(PY_TESTS:tests/shell/%=shell/%.pylint_log)
+else
+  PYLINT_TEST_LOGS :=
+endif
+
+$(OUTPUT)%.pylint_log: %
+	$(call rule_mkdir)
+	$(Q)$(call echo-cmd,test)pylint "$<" > $@ || (cat $@ && rm $@ && false)
+
+perf-test-y += $(PYLINT_TEST_LOGS)

tools/perf/util/Build

@@ -430,3 +430,15 @@ $(OUTPUT)%.mypy_log: %
 	$(Q)$(call echo-cmd,test)mypy "$<" > $@ || (cat $@ && rm $@ && false)
 
 perf-util-y += $(MYPY_TEST_LOGS)
+
+ifdef PYLINT
+  PYLINT_TEST_LOGS := $(PY_TESTS:%=%.pylint_log)
+else
+  PYLINT_TEST_LOGS :=
+endif
+
+$(OUTPUT)%.pylint_log: %
+	$(call rule_mkdir)
+	$(Q)$(call echo-cmd,test)pylint "$<" > $@ || (cat $@ && rm $@ && false)
+
+perf-util-y += $(PYLINT_TEST_LOGS)