From 982be4775164d4780d9c6a2f38b365f5b5bd16d4 Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Tue, 24 May 2022 13:16:20 +0200 Subject: perf build: Stop using __weak btf__raw_data() to handle older libbpf versions MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit By adding a feature test for btf__raw_data() 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-btf__raw_data.make.output test-libbpf-btf__raw_data.c: In function ‘main’: test-libbpf-btf__raw_data.c:6:9: error: implicit declaration of function ‘btf__raw_data’; did you mean ‘btf__get_raw_data’? [-Werror=implicit-function-declaration] 6 | btf__raw_data(NULL /* btf_ro */, NULL /* size */); | ^~~~~~~~~~~~~ | btf__get_raw_data cc1: all warnings being treated as errors $ objdump -dS /tmp/build/perf/perf | grep ':' -A20 00000000005b3050 : { 5b3050: 55 push %rbp 5b3051: 48 89 e5 mov %rsp,%rbp 5b3054: 48 83 ec 10 sub $0x10,%rsp 5b3058: 64 48 8b 04 25 28 00 mov %fs:0x28,%rax 5b305f: 00 00 5b3061: 48 89 45 f8 mov %rax,-0x8(%rbp) 5b3065: 31 c0 xor %eax,%eax return btf__get_raw_data(btf_ro, size); 5b3067: 48 8b 45 f8 mov -0x8(%rbp),%rax 5b306b: 64 48 2b 04 25 28 00 sub %fs:0x28,%rax 5b3072: 00 00 5b3074: 75 06 jne 5b307c } 5b3076: c9 leave return btf__get_raw_data(btf_ro, size); 5b3077: e9 14 99 e5 ff jmp 40c990 5b307c: e8 af a7 e5 ff call 40d830 <__stack_chk_fail@plt> 5b3081: 66 66 2e 0f 1f 84 00 data16 cs nopw 0x0(%rax,%rax,1) 5b3088: 00 00 00 00 $ Signed-off-by: Jiri Olsa Tested-by: Arnaldo Carvalho de Melo Cc: Heiko Carstens Cc: Ian Rogers Cc: Ilya Leoshkevich Cc: Sumanth Korikkar Cc: Sven Schnelle Cc: Thomas Richter Cc: Vasily Gorbik Link: http://lore.kernel.org/linux-perf-users/YozLKby7ITEtchC9@krava Signed-off-by: Arnaldo Carvalho de Melo --- tools/build/feature/Makefile | 4 ++++ tools/build/feature/test-libbpf-btf__raw_data.c | 8 ++++++++ 2 files changed, 12 insertions(+) create mode 100644 tools/build/feature/test-libbpf-btf__raw_data.c (limited to 'tools/build') diff --git a/tools/build/feature/Makefile b/tools/build/feature/Makefile index aecb6a28a770..5b31a6d063d7 100644 --- a/tools/build/feature/Makefile +++ b/tools/build/feature/Makefile @@ -61,6 +61,7 @@ FILES= \ test-libbpf-bpf_prog_load.bin \ test-libbpf-bpf_object__next_program.bin \ test-libbpf-bpf_object__next_map.bin \ + test-libbpf-btf__raw_data.bin \ test-get_cpuid.bin \ test-sdt.bin \ test-cxx.bin \ @@ -303,6 +304,9 @@ $(OUTPUT)test-libbpf-bpf_object__next_program.bin: $(OUTPUT)test-libbpf-bpf_object__next_map.bin: $(BUILD) -lbpf +$(OUTPUT)test-libbpf-btf__raw_data.bin: + $(BUILD) -lbpf + $(OUTPUT)test-sdt.bin: $(BUILD) diff --git a/tools/build/feature/test-libbpf-btf__raw_data.c b/tools/build/feature/test-libbpf-btf__raw_data.c new file mode 100644 index 000000000000..57da31dd7581 --- /dev/null +++ b/tools/build/feature/test-libbpf-btf__raw_data.c @@ -0,0 +1,8 @@ +// SPDX-License-Identifier: GPL-2.0 +#include + +int main(void) +{ + btf__raw_data(NULL /* btf_ro */, NULL /* size */); + return 0; +} -- cgit v1.2.3