From: James Clark <james.clark@xxxxxxx> [ Upstream commit 630af16eee495f583db5202c3613d1b191f10694 ] This fixes the issue where the build will fail if only the Python2 runtime is installed but the Python3 devtools are installed. Currently the workaround is 'make PYTHON=python3'. Fix it by autodetecting Python based on whether python[x]-config exists rather than just python[x] because both are needed for the build. Then -config is stripped to find the Python runtime. Testing ======= * Auto detect links with Python3 when the v3 devtools are installed and only Python 2 runtime is installed * Auto detect links with Python2 when both devtools are installed * Sensible warning is printed if no Python devtools are installed * 'make PYTHON=x' still automatically sets PYTHON_CONFIG=x-config * 'make PYTHON=x' fails if x-config doesn't exist * 'make PYTHON=python3' overrides Python2 devtools * 'make PYTHON=python2' overrides Python3 devtools * 'make PYTHON_CONFIG=x-config' works * 'make PYTHON=x PYTHON_CONFIG=x' works * 'make PYTHON=missing' reports an error * 'make PYTHON_CONFIG=missing' reports an error Fixes: 79373082fa9de8be ("perf python: Autodetect python3 binary") Signed-off-by: James Clark <james.clark@xxxxxxx> Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx> Cc: James Clark <james.clark@xxxxxxx> Cc: Jiri Olsa <jolsa@xxxxxxxxxx> Cc: Mark Rutland <mark.rutland@xxxxxxx> Cc: Namhyung Kim <namhyung@xxxxxxxxxx> Link: https://lore.kernel.org/r/20220309194313.3350126-2-james.clark@xxxxxxx Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- tools/perf/Makefile.config | 39 ++++++++++++++++++++++++++------------ 1 file changed, 27 insertions(+), 12 deletions(-) diff --git a/tools/perf/Makefile.config b/tools/perf/Makefile.config index 1bd64e7404b9..c38423807d01 100644 --- a/tools/perf/Makefile.config +++ b/tools/perf/Makefile.config @@ -239,18 +239,33 @@ ifdef PARSER_DEBUG endif # Try different combinations to accommodate systems that only have -# python[2][-config] in weird combinations but always preferring -# python2 and python2-config as per pep-0394. If python2 or python -# aren't found, then python3 is used. -PYTHON_AUTO := python -PYTHON_AUTO := $(if $(call get-executable,python3),python3,$(PYTHON_AUTO)) -PYTHON_AUTO := $(if $(call get-executable,python),python,$(PYTHON_AUTO)) -PYTHON_AUTO := $(if $(call get-executable,python2),python2,$(PYTHON_AUTO)) -override PYTHON := $(call get-executable-or-default,PYTHON,$(PYTHON_AUTO)) -PYTHON_AUTO_CONFIG := \ - $(if $(call get-executable,$(PYTHON)-config),$(PYTHON)-config,python-config) -override PYTHON_CONFIG := \ - $(call get-executable-or-default,PYTHON_CONFIG,$(PYTHON_AUTO_CONFIG)) +# python[2][3]-config in weird combinations in the following order of +# priority from lowest to highest: +# * python3-config +# * python-config +# * python2-config as per pep-0394. +# * $(PYTHON)-config (If PYTHON is user supplied but PYTHON_CONFIG isn't) +# +PYTHON_AUTO := python-config +PYTHON_AUTO := $(if $(call get-executable,python3-config),python3-config,$(PYTHON_AUTO)) +PYTHON_AUTO := $(if $(call get-executable,python-config),python-config,$(PYTHON_AUTO)) +PYTHON_AUTO := $(if $(call get-executable,python2-config),python2-config,$(PYTHON_AUTO)) + +# If PYTHON is defined but PYTHON_CONFIG isn't, then take $(PYTHON)-config as if it was the user +# supplied value for PYTHON_CONFIG. Because it's "user supplied", error out if it doesn't exist. +ifdef PYTHON + ifndef PYTHON_CONFIG + PYTHON_CONFIG_AUTO := $(call get-executable,$(PYTHON)-config) + PYTHON_CONFIG := $(if $(PYTHON_CONFIG_AUTO),$(PYTHON_CONFIG_AUTO),\ + $(call $(error $(PYTHON)-config not found))) + endif +endif + +# Select either auto detected python and python-config or use user supplied values if they are +# defined. get-executable-or-default fails with an error if the first argument is supplied but +# doesn't exist. +override PYTHON_CONFIG := $(call get-executable-or-default,PYTHON_CONFIG,$(PYTHON_AUTO)) +override PYTHON := $(call get-executable-or-default,PYTHON,$(subst -config,,$(PYTHON_AUTO))) grep-libs = $(filter -l%,$(1)) strip-libs = $(filter-out -l%,$(1)) -- 2.35.1