Commit fbcdaa19 authored by Song Liu's avatar Song Liu Committed by Arnaldo Carvalho de Melo
Browse files

perf build: Support build BPF skeletons with perf 



BPF programs are useful in perf to profile BPF programs.

BPF skeleton is by far the easiest way to write BPF tools. Enable
building BPF skeletons in util/bpf_skel. A dummy bpf skeleton is added.
More bpf skeletons will be added for different use cases.

Signed-off-by: default avatarSong Liu <songliubraving@fb.com>
Tested-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: default avatarJiri Olsa <jolsa@redhat.com>
Acked-by: default avatarNamhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: kernel-team@fb.com
Link: http://lore.kernel.org/lkml/20201229214214.3413833-3-songliubraving@fb.com


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent d2032d45

tools/build/Makefile.feature

+3 −1
Original line number Diff line number Diff line
@@ -99,7 +99,9 @@ FEATURE_TESTS_EXTRA := \ 
         clang                          \

         libbpf                         \

         libpfm4                        \

         libdebuginfod

         libdebuginfod			\

         clang-bpf-co-re





FEATURE_TESTS ?= $(FEATURE_TESTS_BASIC)

tools/perf/Makefile.config

+9 −0
Original line number Diff line number Diff line
@@ -621,6 +621,15 @@ ifndef NO_LIBBPF 
  endif

endif



ifdef BUILD_BPF_SKEL

  $(call feature_check,clang-bpf-co-re)

  ifeq ($(feature-clang-bpf-co-re), 0)

    dummy := $(error Error: clang too old. Please install recent clang)

  endif

  $(call detected,CONFIG_PERF_BPF_SKEL)

  CFLAGS += -DHAVE_BPF_SKEL

endif



dwarf-post-unwind := 1

dwarf-post-unwind-text := BUG

tools/perf/Makefile.perf

+47 −2
Original line number Diff line number Diff line
@@ -126,6 +126,8 @@ include ../scripts/utilities.mak 
#

# Define NO_LIBDEBUGINFOD if you do not want support debuginfod

#

# Define BUILD_BPF_SKEL to enable BPF skeletons

#



# As per kernel Makefile, avoid funny character set dependencies

unexport LC_ALL
@@ -175,6 +177,12 @@ endef 


LD += $(EXTRA_LDFLAGS)



HOSTCC  ?= gcc

HOSTLD  ?= ld

HOSTAR  ?= ar

CLANG   ?= clang

LLVM_STRIP ?= llvm-strip



PKG_CONFIG = $(CROSS_COMPILE)pkg-config

LLVM_CONFIG ?= llvm-config
@@ -731,7 +739,8 @@ prepare: $(OUTPUT)PERF-VERSION-FILE $(OUTPUT)common-cmds.h archheaders $(drm_ioc 
	$(x86_arch_prctl_code_array) \

	$(rename_flags_array) \

	$(arch_errno_name_array) \

	$(sync_file_range_arrays)

	$(sync_file_range_arrays) \

	bpf-skel



$(OUTPUT)%.o: %.c prepare FORCE

	$(Q)$(MAKE) -f $(srctree)/tools/build/Makefile.build dir=$(build-dir) $@
@@ -1004,7 +1013,43 @@ config-clean: 
python-clean:

	$(python-clean)



clean:: $(LIBTRACEEVENT)-clean $(LIBAPI)-clean $(LIBBPF)-clean $(LIBSUBCMD)-clean $(LIBPERF)-clean config-clean fixdep-clean python-clean

SKEL_OUT := $(abspath $(OUTPUT)util/bpf_skel)

SKEL_TMP_OUT := $(abspath $(SKEL_OUT)/.tmp)

SKELETONS :=



ifdef BUILD_BPF_SKEL

BPFTOOL := $(SKEL_TMP_OUT)/bootstrap/bpftool

LIBBPF_SRC := $(abspath ../lib/bpf)

BPF_INCLUDE := -I$(SKEL_TMP_OUT)/.. -I$(BPF_PATH) -I$(LIBBPF_SRC)/..



$(SKEL_TMP_OUT):

	$(Q)$(MKDIR) -p $@



$(BPFTOOL): | $(SKEL_TMP_OUT)

	CFLAGS= $(MAKE) -C ../bpf/bpftool \

		OUTPUT=$(SKEL_TMP_OUT)/ bootstrap



$(SKEL_TMP_OUT)/%.bpf.o: util/bpf_skel/%.bpf.c $(LIBBPF) | $(SKEL_TMP_OUT)

	$(QUIET_CLANG)$(CLANG) -g -O2 -target bpf $(BPF_INCLUDE) \

	  -c $(filter util/bpf_skel/%.bpf.c,$^) -o $@ && $(LLVM_STRIP) -g $@



$(SKEL_OUT)/%.skel.h: $(SKEL_TMP_OUT)/%.bpf.o | $(BPFTOOL)

	$(QUIET_GENSKEL)$(BPFTOOL) gen skeleton $< > $@



bpf-skel: $(SKELETONS)



.PRECIOUS: $(SKEL_TMP_OUT)/%.bpf.o



else # BUILD_BPF_SKEL



bpf-skel:



endif # BUILD_BPF_SKEL



bpf-skel-clean:

	$(call QUIET_CLEAN, bpf-skel) $(RM) -r $(SKEL_TMP_OUT) $(SKELETONS)



clean:: $(LIBTRACEEVENT)-clean $(LIBAPI)-clean $(LIBBPF)-clean $(LIBSUBCMD)-clean $(LIBPERF)-clean config-clean fixdep-clean python-clean bpf-skel-clean

	$(call QUIET_CLEAN, core-objs)  $(RM) $(LIBPERF_A) $(OUTPUT)perf-archive $(OUTPUT)perf-with-kcore $(LANG_BINDINGS)

	$(Q)find $(if $(OUTPUT),$(OUTPUT),.) -name '*.o' -delete -o -name '\.*.cmd' -delete -o -name '\.*.d' -delete

	$(Q)$(RM) $(OUTPUT).config-detected

tools/perf/util/bpf_skel/.gitignore

0 → 100644
+3 −0
Original line number Diff line number Diff line 
# SPDX-License-Identifier: GPL-2.0-only

.tmp

*.skel.h
 
 No newline at end of file

tools/scripts/Makefile.include

+1 −0
Original line number Diff line number Diff line
@@ -127,6 +127,7 @@ ifneq ($(silent),1) 
			 $(MAKE) $(PRINT_DIR) -C $$subdir

	QUIET_FLEX     = @echo '  FLEX     '$@;

	QUIET_BISON    = @echo '  BISON    '$@;

	QUIET_GENSKEL  = @echo '  GEN-SKEL '$@;



	descend = \

		+@echo	       '  DESCEND  '$(1); \