Commit 9925495d authored by Ian Rogers's avatar Ian Rogers Committed by Namhyung Kim
Browse files

perf build: Default BUILD_BPF_SKEL, warn/disable for missing deps 



LIBBPF is dependent on zlib so move the NO_ZLIB and feature check
early to avoid statically building when zlib is disabled. This avoids
a linkage failure with perf and static libbpf when zlib isn't
specified.

Move BUILD_BPF_SKEL logic to one place and if not defined set
BUILD_BPF_SKEL to 1. Detect dependencies of building with BPF
skeletons and warn/disable if the dependencies aren't present.

Change Makefile.perf to contain BPF skeleton logic dependent on the
Makefile.config result and refresh the comment about BUILD_BPF_SKEL.

Signed-off-by: default avatarIan Rogers <irogers@google.com>
Tested-by: default avatarNamhyung Kim <namhyung@kernel.org>
Cc: James Clark <james.clark@arm.com>
Cc: Nick Terrell <terrelln@fb.com>
Cc: Patrice Duroux <patrice.duroux@gmail.com>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Tiezhu Yang <yangtiezhu@loongson.cn>
Cc: Tom Rix <trix@redhat.com>
Cc: llvm@lists.linux.dev
Cc: bpf@vger.kernel.org
Link: https://lore.kernel.org/r/20230914211948.814999-3-irogers@google.com


Signed-off-by: default avatarNamhyung Kim <namhyung@kernel.org>
parent 727e4314

tools/perf/Makefile.config

+49 −29
Original line number Diff line number Diff line
@@ -216,12 +216,6 @@ ifeq ($(call get-executable,$(BISON)),) 
  dummy := $(error Error: $(BISON) is missing on this system, please install it)

endif



ifeq ($(BUILD_BPF_SKEL),1)

  ifeq ($(call get-executable,$(CLANG)),)

    dummy := $(error $(CLANG) is missing on this system, please install it to be able to build with BUILD_BPF_SKEL=1)

  endif

endif



ifneq ($(OUTPUT),)

  ifeq ($(shell expr $(shell $(BISON) --version | grep bison | sed -e 's/.\+ \([0-9]\+\).\([0-9]\+\).\([0-9]\+\)/\1\2\3/g') \>\= 371), 1)

    BISON_FILE_PREFIX_MAP := --file-prefix-map=$(OUTPUT)=
@@ -530,6 +524,16 @@ ifdef CORESIGHT 
  endif

endif



ifndef NO_ZLIB

  ifeq ($(feature-zlib), 1)

    CFLAGS += -DHAVE_ZLIB_SUPPORT

    EXTLIBS += -lz

    $(call detected,CONFIG_ZLIB)

  else

    NO_ZLIB := 1

  endif

endif



ifndef NO_LIBELF

  CFLAGS += -DHAVE_LIBELF_SUPPORT

  EXTLIBS += -lelf
@@ -571,22 +575,28 @@ ifndef NO_LIBELF 


  ifndef NO_LIBBPF

    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

          CFLAGS += -DHAVE_LIBBPF_SUPPORT

          $(call detected,CONFIG_LIBBPF)

          $(call detected,CONFIG_LIBBPF_DYNAMIC)

        else

          dummy := $(error Error: No libbpf devel library found or older than v1.0, please install/update libbpf-devel);

        endif

      else

        ifeq ($(NO_ZLIB), 1)

          dummy := $(warning Warning: Statically building libbpf not possible as zlib is missing)

          NO_LIBBPF := 1

        else

          # Libbpf will be built as a static library from tools/lib/bpf.

          LIBBPF_STATIC := 1

          $(call detected,CONFIG_LIBBPF)

          CFLAGS += -DHAVE_LIBBPF_SUPPORT

        endif

      endif

    endif

  endif # NO_LIBBPF
@@ -663,17 +673,37 @@ ifndef NO_LIBBPF 
  endif

endif



ifdef BUILD_BPF_SKEL

ifndef BUILD_BPF_SKEL

  # BPF skeletons control a large number of perf features, by default

  # they are enabled.

  BUILD_BPF_SKEL := 1

endif



ifeq ($(BUILD_BPF_SKEL),1)

  ifeq ($(filter -DHAVE_LIBBPF_SUPPORT, $(CFLAGS)),)

    dummy := $(warning Warning: Disabled BPF skeletons as libbpf is required)

    BUILD_BPF_SKEL := 0

  else ifeq ($(filter -DHAVE_LIBELF_SUPPORT, $(CFLAGS)),)

    dummy := $(warning Warning: Disabled BPF skeletons as libelf is required by bpftool)

    BUILD_BPF_SKEL := 0

  else ifeq ($(filter -DHAVE_ZLIB_SUPPORT, $(CFLAGS)),)

    dummy := $(warning Warning: Disabled BPF skeletons as zlib is required by bpftool)

    BUILD_BPF_SKEL := 0

  else ifeq ($(call get-executable,$(CLANG)),)

    dummy := $(warning Warning: Disabled BPF skeletons as clang ($(CLANG)) is missing)

    BUILD_BPF_SKEL := 0

  else

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

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

    dummy := $(error Error: clang too old/not installed. Please install recent clang to build with BUILD_BPF_SKEL)

      dummy := $(warning Warning: Disabled BPF skeletons as clang is too old)

      BUILD_BPF_SKEL := 0

    endif

  ifeq ($(filter -DHAVE_LIBBPF_SUPPORT, $(CFLAGS)),)

    dummy := $(error Error: BPF skeleton support requires libbpf)

  endif

  ifeq ($(BUILD_BPF_SKEL),1)

    $(call detected,CONFIG_PERF_BPF_SKEL)

    CFLAGS += -DHAVE_BPF_SKEL

  endif

endif



ifndef GEN_VMLINUX_H

  VMLINUX_H=$(src-perf)/util/bpf_skel/vmlinux/vmlinux.h
@@ -946,16 +976,6 @@ ifndef NO_DEMANGLE 
  endif

endif



ifndef NO_ZLIB

  ifeq ($(feature-zlib), 1)

    CFLAGS += -DHAVE_ZLIB_SUPPORT

    EXTLIBS += -lz

    $(call detected,CONFIG_ZLIB)

  else

    NO_ZLIB := 1

  endif

endif



ifndef NO_LZMA

  ifeq ($(feature-lzma), 1)

    CFLAGS += -DHAVE_LZMA_SUPPORT

tools/perf/Makefile.perf

+4 −4
Original line number Diff line number Diff line
@@ -120,7 +120,7 @@ include ../scripts/utilities.mak 
#

# Define NO_LIBDEBUGINFOD if you do not want support debuginfod

#

# Define BUILD_BPF_SKEL to enable BPF skeletons

# Set BUILD_BPF_SKEL to 0 to override BUILD_BPF_SKEL and not build BPF skeletons

#

# Define BUILD_NONDISTRO to enable building an linking against libbfd and

# libiberty distribution license incompatible libraries.
@@ -1042,7 +1042,7 @@ SKELETONS += $(SKEL_OUT)/augmented_raw_syscalls.skel.h 
$(SKEL_TMP_OUT) $(LIBAPI_OUTPUT) $(LIBBPF_OUTPUT) $(LIBPERF_OUTPUT) $(LIBSUBCMD_OUTPUT) $(LIBSYMBOL_OUTPUT):

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



ifdef BUILD_BPF_SKEL

ifeq ($(CONFIG_PERF_BPF_SKEL),y)

BPFTOOL := $(SKEL_TMP_OUT)/bootstrap/bpftool

# Get Clang's default includes on this system, as opposed to those seen by

# '--target=bpf'. This fixes "missing" files on some architectures/distros,
@@ -1120,11 +1120,11 @@ bpf-skel: $(SKELETONS) 


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



else # BUILD_BPF_SKEL

else # CONFIG_PERF_BPF_SKEL



bpf-skel:



endif # BUILD_BPF_SKEL

endif # CONFIG_PERF_BPF_SKEL



bpf-skel-clean:

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