From: Arnaldo Carvalho de Melo Date: Wed, 11 Dec 2024 19:30:02 +0000 (-0300) Subject: tools build feature: Add some comments to explain the FEATURE_TESTS logic X-Git-Tag: v6.14-rc1~29^2~143 X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=20ed532554a4971c363e1b5529ae13b6d3c28875;p=linux-block.git tools build feature: Add some comments to explain the FEATURE_TESTS logic The tools/build/feature/test-all.c works in conjunction with the tools/build/Makefile.feature FEATURE_TESTS_BASIC and FEATURE_TESTS_EXTRA contents, so that if test-all.c manages to be built, we go on and iterate all entries in FEATURE_TESTS_BASIC + FEATURE_TESTS_EXTRA setting them to 1. To test this: $ rm -rf /tmp/b ; mkdir /tmp/b ; make -C tools/perf O=/tmp/b feature-dump $ cat /tmp/b/feature/test-all.make.output $ ldd /tmp/b/feature/test-all.bin linux-vdso.so.1 (0x00007f2a47a67000) libdw.so.1 => /lib64/libdw.so.1 (0x00007f2a477cf000) libpython3.12.so.1.0 => /lib64/libpython3.12.so.1.0 (0x00007f2a471fe000) libm.so.6 => /lib64/libm.so.6 (0x00007f2a4711a000) libtraceevent.so.1 => /lib64/libtraceevent.so.1 (0x00007f2a470f2000) libtracefs.so.1 => /lib64/libtracefs.so.1 (0x00007f2a470cb000) libcrypto.so.3 => /lib64/libcrypto.so.3 (0x00007f2a46c1b000) libz.so.1 => /lib64/libz.so.1 (0x00007f2a46bf8000) libbabeltrace-ctf.so.1 => /lib64/libbabeltrace-ctf.so.1 (0x00007f2a46bad000) libcapstone.so.5 => /lib64/libcapstone.so.5 (0x00007f2a464b8000) libopencsd_c_api.so.1 => /lib64/libopencsd_c_api.so.1 (0x00007f2a464a8000) libopencsd.so.1 => /lib64/libopencsd.so.1 (0x00007f2a46422000) libelf.so.1 => /lib64/libelf.so.1 (0x00007f2a46406000) libnuma.so.1 => /lib64/libnuma.so.1 (0x00007f2a463f6000) libslang.so.2 => /lib64/libslang.so.2 (0x00007f2a46113000) libperl.so.5.38 => /lib64/libperl.so.5.38 (0x00007f2a45d74000) libc.so.6 => /lib64/libc.so.6 (0x00007f2a45b83000) liblzma.so.5 => /lib64/liblzma.so.5 (0x00007f2a45b50000) libzstd.so.1 => /lib64/libzstd.so.1 (0x00007f2a45a91000) libbz2.so.1 => /lib64/libbz2.so.1 (0x00007f2a45a7b000) /lib64/ld-linux-x86-64.so.2 (0x00007f2a47a69000) libbabeltrace.so.1 => /lib64/libbabeltrace.so.1 (0x00007f2a45a6b000) libpopt.so.0 => /lib64/libpopt.so.0 (0x00007f2a45a5b000) libuuid.so.1 => /lib64/libuuid.so.1 (0x00007f2a45a51000) libgmodule-2.0.so.0 => /lib64/libgmodule-2.0.so.0 (0x00007f2a45a4a000) libglib-2.0.so.0 => /lib64/libglib-2.0.so.0 (0x00007f2a458fa000) libstdc++.so.6 => /lib64/libstdc++.so.6 (0x00007f2a45696000) libgcc_s.so.1 => /lib64/libgcc_s.so.1 (0x00007f2a45668000) libcrypt.so.2 => /lib64/libcrypt.so.2 (0x00007f2a45630000) libpcre2-8.so.0 => /lib64/libpcre2-8.so.0 (0x00007f2a45590000) $ head /tmp/b/FEATURE-DUMP feature-backtrace=1 feature-libdw=1 feature-eventfd=1 feature-fortify-source=1 feature-get_current_dir_name=1 feature-gettid=1 feature-glibc=1 feature-libbfd=1 feature-libbfd-buildid=1 feature-libcap=1 $ There are inconsistencies that are being audited, as can be seen above with the libcap case, that is not linked with test-all.bin nor is present in test-all.c, so shouldn't be set as present. Further patches are going to address those inconsistencies, but lets document this a bit more to reduce the chances of this happening again. Reviewed-by: Ian Rogers Cc: Adrian Hunter Cc: James Clark Cc: Jiri Olsa Cc: Kan Liang Cc: Namhyung Kim Link: https://lore.kernel.org/lkml/20241211224509.797827-2-acme@kernel.org [ Fixed typo pointed out by Ian Rogers ] Signed-off-by: Arnaldo Carvalho de Melo --- diff --git a/tools/build/Makefile.feature b/tools/build/Makefile.feature index 805631543186..52600e4d33af 100644 --- a/tools/build/Makefile.feature +++ b/tools/build/Makefile.feature @@ -28,6 +28,41 @@ endef # the rule that uses them - an example for that is the 'bionic' # feature check. ] # +# These + the ones in FEATURE_TESTS_EXTRA are included in +# tools/build/feature/test-all.c and we try to build it all together +# then setting all those features to '1' meaning they are all enabled. +# +# There are things like fortify-source that will be set to 1 because test-all +# is built with the flags needed to test if its enabled, resulting in +# +# $ rm -rf /tmp/b ; mkdir /tmp/b ; make -C tools/perf O=/tmp/b feature-dump +# $ grep fortify-source /tmp/b/FEATURE-DUMP +# feature-fortify-source=1 +# $ +# +# All the others should have lines in tools/build/feature/test-all.c like: +# +# #define main main_test_disassembler_init_styled +# # include "test-disassembler-init-styled.c" +# #undef main +# +# #define main main_test_libzstd +# # include "test-libzstd.c" +# #undef main +# +# int main(int argc, char *argv[]) +# { +# main_test_disassembler_four_args(); +# main_test_libzstd(); +# return 0; +# } +# +# If the sample above works, then we end up with these lines in the FEATURE-DUMP +# file: +# +# feature-disassembler-four-args=1 +# feature-libzstd=1 +# FEATURE_TESTS_BASIC := \ backtrace \ libdw \