linux/tools/build/feature
Arnaldo Carvalho de Melo 3d1d57debe tools build: Remove needless libpython-version feature check that breaks test-all fast path
Since 66dfdff03d ("perf tools: Add Python 3 support") we don't use
the tools/build/feature/test-libpython-version.c version in any Makefile
feature check:

  $ find tools/ -type f | xargs grep feature-libpython-version
  $

The only place where this was used was removed in 66dfdff03d:

  -        ifneq ($(feature-libpython-version), 1)
  -          $(warning Python 3 is not yet supported; please set)
  -          $(warning PYTHON and/or PYTHON_CONFIG appropriately.)
  -          $(warning If you also have Python 2 installed, then)
  -          $(warning try something like:)
  -          $(warning $(and ,))
  -          $(warning $(and ,)  make PYTHON=python2)
  -          $(warning $(and ,))
  -          $(warning Otherwise, disable Python support entirely:)
  -          $(warning $(and ,))
  -          $(warning $(and ,)  make NO_LIBPYTHON=1)
  -          $(warning $(and ,))
  -          $(error   $(and ,))
  -        else
  -          LDFLAGS += $(PYTHON_EMBED_LDFLAGS)
  -          EXTLIBS += $(PYTHON_EMBED_LIBADD)
  -          LANG_BINDINGS += $(obj-perf)python/perf.so
  -          $(call detected,CONFIG_LIBPYTHON)
  -        endif

And nowadays we either build with PYTHON=python3 or just install the
python3 devel packages and perf will build against it.

But the leftover feature-libpython-version check made the fast path
feature detection to break in all cases except when python2 devel files
were installed:

  $ rpm -qa | grep python.*devel
  python3-devel-3.9.7-1.fc34.x86_64
  $ rm -rf /tmp/build/perf ; mkdir -p /tmp/build/perf ;
  $ make -C tools/perf O=/tmp/build/perf install-bin
  make: Entering directory '/var/home/acme/git/perf/tools/perf'
    BUILD:   Doing 'make -j32' parallel build
    HOSTCC  /tmp/build/perf/fixdep.o
  <SNIP>
  $ cat /tmp/build/perf/feature/test-all.make.output
  In file included from test-all.c:18:
  test-libpython-version.c:5:10: error: #error
      5 |         #error
        |          ^~~~~
  $ ldd ~/bin/perf | grep python
	libpython3.9.so.1.0 => /lib64/libpython3.9.so.1.0 (0x00007fda6dbcf000)
  $

As python3 is the norm these days, fix this by just removing the unused
feature-libpython-version feature check, making the test-all fast path
to work with the common case.

With this:

  $ rm -rf /tmp/build/perf ; mkdir -p /tmp/build/perf ;
  $ make -C tools/perf O=/tmp/build/perf install-bin |& head
  make: Entering directory '/var/home/acme/git/perf/tools/perf'
    BUILD:   Doing 'make -j32' parallel build
    HOSTCC  /tmp/build/perf/fixdep.o
    HOSTLD  /tmp/build/perf/fixdep-in.o
    LINK    /tmp/build/perf/fixdep

  Auto-detecting system features:
  ...                         dwarf: [ on  ]
  ...            dwarf_getlocations: [ on  ]
  ...                         glibc: [ on  ]
  $ ldd ~/bin/perf | grep python
	libpython3.9.so.1.0 => /lib64/libpython3.9.so.1.0 (0x00007f58800b0000)
  $ cat /tmp/build/perf/feature/test-all.make.output
  $

Reviewed-by: James Clark <james.clark@arm.com>
Fixes: 66dfdff03d ("perf tools: Add Python 3 support")
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jaroslav Škarvada <jskarvad@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/lkml/YaYmeeC6CS2b8OSz@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2021-12-06 21:57:53 -03:00
..
.gitignore .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
Makefile tools build: Remove needless libpython-version feature check that breaks test-all fast path 2021-12-06 21:57:53 -03:00
test-all.c tools build: Remove needless libpython-version feature check that breaks test-all fast path 2021-12-06 21:57:53 -03:00
test-backtrace.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-bionic.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-bpf.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-clang-bpf-co-re.c tools/bpftool: Generalize BPF skeleton support and generate vmlinux.h 2020-06-22 17:01:48 -07:00
test-clang.cpp tools build: Fix test-clang.cpp with Clang 8+ 2020-01-14 12:02:19 -03:00
test-compile.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-cplus-demangle.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-cxx.cpp License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-disassembler-four-args.c tools/bpftool: fix bpftool build with bintutils >= 2.9 2017-12-30 01:07:36 +01:00
test-dwarf_getlocations.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-dwarf.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-eventfd.c tools build feature: Check if eventfd() is available 2018-11-21 22:25:44 -03:00
test-file-handle.c perf tools: Add file-handle feature test 2020-04-03 09:37:55 -03:00
test-fortify-source.c tools build feature tests: Add missing SPDX headers 2019-06-17 15:57:19 -03:00
test-get_cpuid.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-get_current_dir_name.c tools feature: Undef _GNU_SOURCE at the end of feature tests 2019-02-14 13:31:11 -03:00
test-gettid.c tools build: Check if gettid() is available before providing helper 2019-06-17 15:57:19 -03:00
test-glibc.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-gtk2-infobar.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-gtk2.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-hello.c tools build feature tests: Add missing SPDX headers 2019-06-17 15:57:19 -03:00
test-jvmti-cmlr.c perf jvmti: Separate jvmti cmlr check 2018-11-21 22:39:58 -03:00
test-jvmti.c perf jvmti: Separate jvmti cmlr check 2018-11-21 22:39:58 -03:00
test-libaio.c tools build feature: Check if libaio is available 2018-12-17 14:54:54 -03:00
test-libaudit.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-libbabeltrace.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-libbfd-buildid.c tools features: Add feature test to check if libbfd has buildid support 2020-09-04 14:38:15 -03:00
test-libbfd.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-libbpf.c perf tools: Allow to link with libbpf dynamicaly 2019-11-26 11:17:45 -03:00
test-libcap.c tools build: Add capability-related feature detection 2019-08-12 17:14:14 -03:00
test-libcrypto.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-libdebuginfod.c perf build-ids: Fall back to debuginfod query if debuginfo not found 2020-08-14 09:51:14 -03:00
test-libdw-dwarf-unwind.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-libelf-gelf_getnote.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-libelf-getphdrnum.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-libelf-getshdrstrndx.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-libelf.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-libnuma.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-libopencsd.c perf cs-etm: Update OpenCSD decoder for ETE 2021-09-03 08:16:00 -03:00
test-libperl.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-libpfm4.c tools feature: Add support for detecting libpfm4 2020-05-05 16:35:31 -03:00
test-libpython.c tools feature: Undef _GNU_SOURCE at the end of feature tests 2019-02-14 13:31:11 -03:00
test-libslang-include-subdir.c tools build: Add test to check if slang.h is in /usr/include/slang/ 2019-06-18 17:43:35 -03:00
test-libslang.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-libtraceevent.c perf tools: Enable libtraceevent dynamic linking 2021-04-29 10:31:00 -03:00
test-libtracefs.c perf tools: Enable libtracefs dynamic linking 2021-09-28 16:08:37 -03:00
test-libunwind-aarch64.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-libunwind-arm.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-libunwind-debug-frame-aarch64.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-libunwind-debug-frame-arm.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-libunwind-debug-frame.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-libunwind-x86_64.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-libunwind-x86.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-libunwind.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-libzstd.c tools build: Implement libzstd feature check, LIBZSTD_DIR and NO_LIBZSTD defines 2019-04-01 15:18:10 -03:00
test-llvm-version.cpp License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-llvm.cpp License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-lzma.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-numa_num_possible_cpus.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-pthread-attr-setaffinity-np.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-pthread-barrier.c tools build feature: Check if pthread_barrier_t is available 2017-12-05 10:21:59 -03:00
test-reallocarray.c tools build: Add test-reallocarray.c to test-all.c to fix the build 2019-02-14 15:18:05 -03:00
test-sched_getcpu.c tools build feature sched_getcpu: Undef _GNU_SOURCE at the end 2019-02-14 15:39:21 -03:00
test-sdt.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-setns.c tools build feature tests: Add missing SPDX headers 2019-06-17 15:57:19 -03:00
test-stackprotector-all.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-timerfd.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test-zlib.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00