linux/tools/build/feature
Jiri Olsa 739c9180cf perf build: Stop using __weak bpf_object__next_map() to handle older libbpf versions
By adding a feature test for bpf_object__next_map() and providing a fallback if
it isn't present in older versions of libbpf.

Committer testing:

  $ rpm -q libbpf-devel
  libbpf-devel-0.4.0-2.fc35.x86_64
  $ make -C tools/perf LIBBPF_DYNAMIC=1 O=/tmp/build/perf install-bin
  $ cat /tmp/build/perf/feature/test-libbpf-bpf_object__next_map.make.output
  test-libbpf-bpf_object__next_map.c: In function ‘main’:
  test-libbpf-bpf_object__next_map.c:6:9: error: implicit declaration of function ‘bpf_object__next_map’; did you mean ‘bpf_object__next’? [-Werror=implicit-function-declaration]
      6 |         bpf_object__next_map(NULL /* obj */, NULL /* prev */);
        |         ^~~~~~~~~~~~~~~~~~~~
        |         bpf_object__next
    cc1: all warnings being treated as errors
  $
  $ objdump -dS /tmp/build/perf/perf | grep '<bpf_object__next_map>:' -A20
  00000000005b2e00 <bpf_object__next_map>:
  {
    5b2e00:	55                   	push   %rbp
    5b2e01:	48 89 e5             	mov    %rsp,%rbp
    5b2e04:	48 83 ec 10          	sub    $0x10,%rsp
    5b2e08:	64 48 8b 04 25 28 00 	mov    %fs:0x28,%rax
    5b2e0f:	00 00
    5b2e11:	48 89 45 f8          	mov    %rax,-0x8(%rbp)
    5b2e15:	31 c0                	xor    %eax,%eax
	  return bpf_map__next(prev, obj);
    5b2e17:	48 8b 45 f8          	mov    -0x8(%rbp),%rax
    5b2e1b:	64 48 2b 04 25 28 00 	sub    %fs:0x28,%rax
    5b2e22:	00 00
    5b2e24:	75 0f                	jne    5b2e35 <bpf_object__next_map+0x35>
  }
    5b2e26:	c9                   	leave
    5b2e27:	49 89 f8             	mov    %rdi,%r8
    5b2e2a:	48 89 f7             	mov    %rsi,%rdi
	  return bpf_map__next(prev, obj);
    5b2e2d:	4c 89 c6             	mov    %r8,%rsi
    5b2e30:	e9 cb b1 e5 ff       	jmp    40e000 <bpf_map__next@plt>
  $

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ilya Leoshkevich <iii@linux.ibm.com>
Cc: Sumanth Korikkar <sumanthk@linux.ibm.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Link: http://lore.kernel.org/linux-perf-users/YozLKby7ITEtchC9@krava
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-05-26 11:02:02 -03:00
..
.gitignore .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
Makefile perf build: Stop using __weak bpf_object__next_map() to handle older libbpf versions 2022-05-26 11:02:02 -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 bpf, mips: Fix build errors about __NR_bpf undeclared 2021-11-26 22:11:25 +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-bpf_object__next_map.c perf build: Stop using __weak bpf_object__next_map() to handle older libbpf versions 2022-05-26 11:02:02 -03:00
test-libbpf-bpf_object__next_program.c perf build: Stop using __weak bpf_object__next_program() to handle older libbpf versions 2022-05-26 11:02:02 -03:00
test-libbpf-bpf_prog_load.c perf build: Stop using __weak bpf_prog_load() to handle older libbpf versions 2022-05-26 11:02:02 -03:00
test-libbpf-btf__load_from_kernel_by_id.c perf build: Fix btf__load_from_kernel_by_id() feature check 2022-05-26 11:02:02 -03:00
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