linux-yocto/tools/lib/bpf/Makefile

SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)

Most of this file is copied from tools/lib/traceevent/Makefile

BPF_VERSION = 0 BPF_PATCHLEVEL = 0 BPF_EXTRAVERSION = 3

MAKEFLAGS += --no-print-directory

ifeq ($(srctree),) srctree := $(patsubst %/,%,$(dir $(CURDIR))) srctree := $(patsubst %/,%,$(dir $(srctree))) srctree := $(patsubst %/,%,$(dir $(srctree))) #$(info Determined 'srctree' to be $(srctree)) endif

INSTALL = install

Use DESTDIR for installing into a different root directory.

This is useful for building a package. The program will be

installed in this directory as if it was the root directory.

Then the build tool can move it later.

DESTDIR ?= DESTDIR_SQ = '$(subst ',''',$(DESTDIR))'

include $(srctree)/tools/scripts/Makefile.arch

ifeq ($(LP64), 1) libdir_relative = lib64 else libdir_relative = lib endif

prefix ?= /usr/local libdir = $(prefix)/$(libdir_relative) man_dir = $(prefix)/share/man man_dir_SQ = '$(subst ',''',$(man_dir))'

export man_dir man_dir_SQ INSTALL export DESTDIR DESTDIR_SQ

include $(srctree)/tools/scripts/Makefile.include

copy a bit from Linux kbuild

ifeq ("$(origin V)", "command line") VERBOSE = $(V) endif ifndef VERBOSE VERBOSE = 0 endif

FEATURE_USER = .libbpf FEATURE_TESTS = libelf libelf-mmap bpf reallocarray cxx FEATURE_DISPLAY = libelf bpf

INCLUDES = -I. -I$(srctree)/tools/include -I$(srctree)/tools/arch/$(ARCH)/include/uapi -I$(srctree)/tools/include/uapi FEATURE_CHECK_CFLAGS-bpf = $(INCLUDES)

check_feat := 1 NON_CHECK_FEAT_TARGETS := clean TAGS tags cscope help ifdef MAKECMDGOALS ifeq ($(filter-out $(NON_CHECK_FEAT_TARGETS),$(MAKECMDGOALS)),) check_feat := 0 endif endif

ifeq ($(check_feat),1) ifeq ($(FEATURES_DUMP),) include $(srctree)/tools/build/Makefile.feature else include $(FEATURES_DUMP) endif endif

export prefix libdir src obj

Shell quotes

libdir_SQ = $(subst ',''',$(libdir)) libdir_relative_SQ = $(subst ',''',$(libdir_relative))

VERSION = $(BPF_VERSION) PATCHLEVEL = $(BPF_PATCHLEVEL) EXTRAVERSION = $(BPF_EXTRAVERSION)

OBJ = $@ N =

LIBBPF_VERSION = $(BPF_VERSION).$(BPF_PATCHLEVEL).$(BPF_EXTRAVERSION)

LIB_TARGET = libbpf.a libbpf.so.$(LIBBPF_VERSION) LIB_FILE = libbpf.a libbpf.so* PC_FILE = libbpf.pc

Set compile option CFLAGS

ifdef EXTRA_CFLAGS CFLAGS := $(EXTRA_CFLAGS) else CFLAGS := -g -Wall endif

ifeq ($(feature-libelf-mmap), 1) override CFLAGS += -DHAVE_LIBELF_MMAP_SUPPORT endif

ifeq ($(feature-reallocarray), 0) override CFLAGS += -DCOMPAT_NEED_REALLOCARRAY endif

Append required CFLAGS

override CFLAGS += $(EXTRA_WARNINGS) override CFLAGS += -Werror -Wall override CFLAGS += -fPIC override CFLAGS += $(INCLUDES) override CFLAGS += -fvisibility=hidden

ifeq ($(VERBOSE),1) Q = else Q = @ endif

Disable command line variables (CFLAGS) override from top

level Makefile (perf), otherwise build Makefile will get

the same command line setup.

MAKEOVERRIDES=

all:

export srctree OUTPUT CC LD CFLAGS V include $(srctree)/tools/build/Makefile.include

BPF_IN := $(OUTPUT)libbpf-in.o VERSION_SCRIPT := libbpf.map

LIB_TARGET := $(addprefix $(OUTPUT),$(LIB_TARGET)) LIB_FILE := $(addprefix $(OUTPUT),$(LIB_FILE)) PC_FILE := $(addprefix $(OUTPUT),$(PC_FILE))

GLOBAL_SYM_COUNT = $(shell readelf -s --wide $(BPF_IN) |
awk '/GLOBAL/ && /DEFAULT/ && !/UND/ {s++} END{print s}') VERSIONED_SYM_COUNT = $(shell readelf -s --wide $(OUTPUT)libbpf.so |
grep -Eo '[^ ]+@LIBBPF_' | cut -d@ -f1 | sort -u | wc -l)

CMD_TARGETS = $(LIB_TARGET) $(PC_FILE)

CXX_TEST_TARGET = $(OUTPUT)test_libbpf

ifeq ($(feature-cxx), 1) CMD_TARGETS += $(CXX_TEST_TARGET) endif

TARGETS = $(CMD_TARGETS)

all: fixdep $(Q)$(MAKE) all_cmd

all_cmd: $(CMD_TARGETS) check

$(BPF_IN): force elfdep bpfdep @(test -f ../../include/uapi/linux/bpf.h -a -f ../../../include/uapi/linux/bpf.h && (
(diff -B ../../include/uapi/linux/bpf.h ../../../include/uapi/linux/bpf.h >/dev/null) ||
echo "Warning: Kernel ABI header at 'tools/include/uapi/linux/bpf.h' differs from latest version at 'include/uapi/linux/bpf.h'" >&2 )) || true @(test -f ../../include/uapi/linux/bpf_common.h -a -f ../../../include/uapi/linux/bpf_common.h && (
(diff -B ../../include/uapi/linux/bpf_common.h ../../../include/uapi/linux/bpf_common.h >/dev/null) ||
echo "Warning: Kernel ABI header at 'tools/include/uapi/linux/bpf_common.h' differs from latest version at 'include/uapi/linux/bpf_common.h'" >&2 )) || true @(test -f ../../include/uapi/linux/netlink.h -a -f ../../../include/uapi/linux/netlink.h && (
(diff -B ../../include/uapi/linux/netlink.h ../../../include/uapi/linux/netlink.h >/dev/null) ||
echo "Warning: Kernel ABI header at 'tools/include/uapi/linux/netlink.h' differs from latest version at 'include/uapi/linux/netlink.h'" >&2 )) || true @(test -f ../../include/uapi/linux/if_link.h -a -f ../../../include/uapi/linux/if_link.h && (
(diff -B ../../include/uapi/linux/if_link.h ../../../include/uapi/linux/if_link.h >/dev/null) ||
echo "Warning: Kernel ABI header at 'tools/include/uapi/linux/if_link.h' differs from latest version at 'include/uapi/linux/if_link.h'" >&2 )) || true @(test -f ../../include/uapi/linux/if_xdp.h -a -f ../../../include/uapi/linux/if_xdp.h && (
(diff -B ../../include/uapi/linux/if_xdp.h ../../../include/uapi/linux/if_xdp.h >/dev/null) ||
echo "Warning: Kernel ABI header at 'tools/include/uapi/linux/if_xdp.h' differs from latest version at 'include/uapi/linux/if_xdp.h'" >&2 )) || true $(Q)$(MAKE) $(build)=libbpf

$(OUTPUT)libbpf.so: $(OUTPUT)libbpf.so.$(LIBBPF_VERSION)

$(OUTPUT)libbpf.so.$(LIBBPF_VERSION): $(BPF_IN) $(QUIET_LINK)$(CC) --shared -Wl,-soname,libbpf.so.$(VERSION)
-Wl,--version-script=$(VERSION_SCRIPT) $^ -lelf -o $@ @ln -sf $(@F) $(OUTPUT)libbpf.so @ln -sf $(@F) $(OUTPUT)libbpf.so.$(VERSION)

$(OUTPUT)libbpf.a: $(BPF_IN) $(QUIET_LINK)$(RM) $@; $(AR) rcs $@ $^

$(OUTPUT)test_libbpf: test_libbpf.cpp $(OUTPUT)libbpf.a $(QUIET_LINK)$(CXX) $(INCLUDES) $^ -lelf -o $@

$(OUTPUT)libbpf.pc: $(QUIET_GEN)sed -e "s|@PREFIX@|$(prefix)|"
-e "s|@LIBDIR@|$(libdir_SQ)|"
-e "s|@VERSION@|$(LIBBPF_VERSION)|"
< libbpf.pc.template > $@

check: check_abi

check_abi: $(OUTPUT)libbpf.so @if [ "$(GLOBAL_SYM_COUNT)" != "$(VERSIONED_SYM_COUNT)" ]; then
echo "Warning: Num of global symbols in $(BPF_IN)"
"($(GLOBAL_SYM_COUNT)) does NOT match with num of"
"versioned symbols in $^ ($(VERSIONED_SYM_COUNT))."
"Please make sure all LIBBPF_API symbols are"
"versioned in $(VERSION_SCRIPT)." >&2;
exit 1;
fi

define do_install_mkdir if [ ! -d '$(DESTDIR_SQ)$1' ]; then
$(INSTALL) -d -m 755 '$(DESTDIR_SQ)$1';
fi endef

define do_install if [ ! -d '$(DESTDIR_SQ)$2' ]; then
$(INSTALL) -d -m 755 '$(DESTDIR_SQ)$2';
fi;
$(INSTALL) $1 $(if $3,-m $3,) '$(DESTDIR_SQ)$2' endef

install_lib: all_cmd $(call QUIET_INSTALL, $(LIB_TARGET))
$(call do_install_mkdir,$(libdir_SQ));
cp -fpR $(LIB_FILE) $(DESTDIR)$(libdir_SQ)

install_headers: $(call QUIET_INSTALL, headers)
$(call do_install,bpf.h,$(prefix)/include/bpf,644);
$(call do_install,libbpf.h,$(prefix)/include/bpf,644);
$(call do_install,btf.h,$(prefix)/include/bpf,644);
$(call do_install,libbpf_util.h,$(prefix)/include/bpf,644);
$(call do_install,xsk.h,$(prefix)/include/bpf,644);

install_pkgconfig: $(PC_FILE) $(call QUIET_INSTALL, $(PC_FILE))
$(call do_install,$(PC_FILE),$(libdir_SQ)/pkgconfig,644)

install: install_lib install_pkgconfig

Cleaning rules

config-clean: $(call QUIET_CLEAN, config) $(Q)$(MAKE) -C $(srctree)/tools/build/feature/ clean >/dev/null

clean: $(call QUIET_CLEAN, libbpf) $(RM) $(TARGETS) $(CXX_TEST_TARGET)
*.o *~ *.a .so .so.$(VERSION) ..d ..cmd *.pc LIBBPF-CFLAGS $(call QUIET_CLEAN, core-gen) $(RM) $(OUTPUT)FEATURE-DUMP.libbpf

PHONY += force elfdep bpfdep force:

elfdep: @if [ "$(feature-libelf)" != "1" ]; then echo "No libelf found"; exit 1 ; fi

bpfdep: @if [ "$(feature-bpf)" != "1" ]; then echo "BPF API too old"; exit 1 ; fi

Declare the contents of the .PHONY variable as phony. We keep that

information in a variable so we can use it in if_changed and friends.

.PHONY: $(PHONY)