The following commit has been merged into the perf/urgent branch of tip: Commit-ID: 7b65e2034fde011d090d4ec472902b71129c6cbd Gitweb: https://git.kernel.org/tip/7b65e2034fde011d090d4ec472902b71129c6cbd Author: Jiri Olsa <jolsa@xxxxxxxxxx> AuthorDate: Tue, 26 Nov 2019 13:12:53 +01:00 Committer: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> CommitterDate: Tue, 26 Nov 2019 11:17:45 -03:00 perf tools: Allow to link with libbpf dynamicaly Currently we support only static linking with kernel's libbpf (tools/lib/bpf). This patch adds libbpf package detection and support to link perf with it dynamically. The libbpf package status is displayed with: $ make VF=1 Auto-detecting system features: ... ... libbpf: [ on ] It's not checked by default, because it's quite new. Once it's on most distros we can switch it on. For the same reason it's not added to the test-all check. Perf does not need advanced version of libbpf, so we can check just for the base bpf_object__open function. Adding new compile variable to detect libbpf package and link bpf dynamically: $ make LIBBPF_DYNAMIC=1 ... LINK perf $ ldd perf | grep bpf libbpf.so.0 => /lib64/libbpf.so.0 (0x00007f46818bc000) If libbpf is not installed, build stops with: Makefile.config:486: *** Error: No libbpf devel library found,\ please install libbpf-devel. Stop. Committer testing: $ make LIBBPF_DYNAMIC=1 -C tools/perf O=/tmp/build/perf make: Entering directory '/home/acme/git/perf/tools/perf' BUILD: Doing 'make -j8' parallel build Makefile.config:493: *** Error: No libbpf devel library found, please install libbpf-devel. Stop. make[1]: *** [Makefile.perf:225: sub-make] Error 2 make: *** [Makefile:70: all] Error 2 make: Leaving directory '/home/acme/git/perf/tools/perf' $ Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx> Tested-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> Cc: Toke Høiland-Jørgensen <toke@xxxxxxxxxx> Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx> Cc: Alexei Starovoitov <alexei.starovoitov@xxxxxxxxx> Cc: Andrii Nakryiko <andriin@xxxxxx> Cc: Daniel Borkmann <daniel@xxxxxxxxxxxxx> Cc: Jesper Dangaard Brouer <brouer@xxxxxxxxxx> Cc: Martin KaFai Lau <kafai@xxxxxx> Cc: Michael Petlan <mpetlan@xxxxxxxxxx> Cc: Namhyung Kim <namhyung@xxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Song Liu <songliubraving@xxxxxx> Cc: Yonghong Song <yhs@xxxxxx> Cc: bpf@xxxxxxxxxxxxxxx Cc: netdev@xxxxxxxxxxxxxxx Link: http://lore.kernel.org/lkml/20191126121253.28253-1-jolsa@xxxxxxxxxx Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> --- tools/build/Makefile.feature | 3 ++- tools/build/feature/Makefile | 4 ++++ tools/build/feature/test-libbpf.c | 7 +++++++ tools/perf/Makefile.config | 10 ++++++++++ tools/perf/Makefile.perf | 6 +++++- 5 files changed, 28 insertions(+), 2 deletions(-) create mode 100644 tools/build/feature/test-libbpf.c diff --git a/tools/build/Makefile.feature b/tools/build/Makefile.feature index 8a19753..574c2e0 100644 --- a/tools/build/Makefile.feature +++ b/tools/build/Makefile.feature @@ -96,7 +96,8 @@ FEATURE_TESTS_EXTRA := \ cxx \ llvm \ llvm-version \ - clang + clang \ + libbpf FEATURE_TESTS ?= $(FEATURE_TESTS_BASIC) diff --git a/tools/build/feature/Makefile b/tools/build/feature/Makefile index 8499385..f30a890 100644 --- a/tools/build/feature/Makefile +++ b/tools/build/feature/Makefile @@ -53,6 +53,7 @@ FILES= \ test-zlib.bin \ test-lzma.bin \ test-bpf.bin \ + test-libbpf.bin \ test-get_cpuid.bin \ test-sdt.bin \ test-cxx.bin \ @@ -270,6 +271,9 @@ $(OUTPUT)test-get_cpuid.bin: $(OUTPUT)test-bpf.bin: $(BUILD) +$(OUTPUT)test-libbpf.bin: + $(BUILD) -lbpf + $(OUTPUT)test-sdt.bin: $(BUILD) diff --git a/tools/build/feature/test-libbpf.c b/tools/build/feature/test-libbpf.c new file mode 100644 index 0000000..a508756 --- /dev/null +++ b/tools/build/feature/test-libbpf.c @@ -0,0 +1,7 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <bpf/libbpf.h> + +int main(void) +{ + return bpf_object__open("test") ? 0 : -1; +} diff --git a/tools/perf/Makefile.config b/tools/perf/Makefile.config index 1783427..c90f414 100644 --- a/tools/perf/Makefile.config +++ b/tools/perf/Makefile.config @@ -483,6 +483,16 @@ ifndef NO_LIBELF ifeq ($(feature-bpf), 1) CFLAGS += -DHAVE_LIBBPF_SUPPORT $(call detected,CONFIG_LIBBPF) + + # detecting libbpf without LIBBPF_DYNAMIC, so make VF=1 shows libbpf detection status + $(call feature_check,libbpf) + ifdef LIBBPF_DYNAMIC + ifeq ($(feature-libbpf), 1) + EXTLIBS += -lbpf + else + dummy := $(error Error: No libbpf devel library found, please install libbpf-devel); + endif + endif endif ifndef NO_DWARF diff --git a/tools/perf/Makefile.perf b/tools/perf/Makefile.perf index 1cd2944..eae5d5e 100644 --- a/tools/perf/Makefile.perf +++ b/tools/perf/Makefile.perf @@ -116,6 +116,8 @@ include ../scripts/utilities.mak # # Define TCMALLOC to enable tcmalloc heap profiling. # +# Define LIBBPF_DYNAMIC to enable libbpf dynamic linking. +# # As per kernel Makefile, avoid funny character set dependencies unexport LC_ALL @@ -360,7 +362,9 @@ export PERL_PATH PERFLIBS = $(LIBAPI) $(LIBTRACEEVENT) $(LIBSUBCMD) $(LIBPERF) ifndef NO_LIBBPF - PERFLIBS += $(LIBBPF) + ifndef LIBBPF_DYNAMIC + PERFLIBS += $(LIBBPF) + endif endif # We choose to avoid "if .. else if .. else .. endif endif"
