1# SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) 2# Most of this file is copied from tools/lib/traceevent/Makefile 3 4BPF_VERSION = 0 5BPF_PATCHLEVEL = 0 6BPF_EXTRAVERSION = 1 7 8MAKEFLAGS += --no-print-directory 9 10ifeq ($(srctree),) 11srctree := $(patsubst %/,%,$(dir $(CURDIR))) 12srctree := $(patsubst %/,%,$(dir $(srctree))) 13srctree := $(patsubst %/,%,$(dir $(srctree))) 14#$(info Determined 'srctree' to be $(srctree)) 15endif 16 17# Makefiles suck: This macro sets a default value of $(2) for the 18# variable named by $(1), unless the variable has been set by 19# environment or command line. This is necessary for CC and AR 20# because make sets default values, so the simpler ?= approach 21# won't work as expected. 22define allow-override 23 $(if $(or $(findstring environment,$(origin $(1))),\ 24 $(findstring command line,$(origin $(1)))),,\ 25 $(eval $(1) = $(2))) 26endef 27 28# Allow setting CC and AR, or setting CROSS_COMPILE as a prefix. 29$(call allow-override,CC,$(CROSS_COMPILE)gcc) 30$(call allow-override,AR,$(CROSS_COMPILE)ar) 31 32INSTALL = install 33 34# Use DESTDIR for installing into a different root directory. 35# This is useful for building a package. The program will be 36# installed in this directory as if it was the root directory. 37# Then the build tool can move it later. 38DESTDIR ?= 39DESTDIR_SQ = '$(subst ','\'',$(DESTDIR))' 40 41include $(srctree)/tools/scripts/Makefile.arch 42 43ifeq ($(LP64), 1) 44 libdir_relative = lib64 45else 46 libdir_relative = lib 47endif 48 49prefix ?= /usr/local 50libdir = $(prefix)/$(libdir_relative) 51man_dir = $(prefix)/share/man 52man_dir_SQ = '$(subst ','\'',$(man_dir))' 53 54export man_dir man_dir_SQ INSTALL 55export DESTDIR DESTDIR_SQ 56 57include ../../scripts/Makefile.include 58 59# copy a bit from Linux kbuild 60 61ifeq ("$(origin V)", "command line") 62 VERBOSE = $(V) 63endif 64ifndef VERBOSE 65 VERBOSE = 0 66endif 67 68FEATURE_USER = .libbpf 69FEATURE_TESTS = libelf libelf-mmap bpf reallocarray cxx 70FEATURE_DISPLAY = libelf bpf 71 72INCLUDES = -I. -I$(srctree)/tools/include -I$(srctree)/tools/arch/$(ARCH)/include/uapi -I$(srctree)/tools/include/uapi 73FEATURE_CHECK_CFLAGS-bpf = $(INCLUDES) 74 75check_feat := 1 76NON_CHECK_FEAT_TARGETS := clean TAGS tags cscope help 77ifdef MAKECMDGOALS 78ifeq ($(filter-out $(NON_CHECK_FEAT_TARGETS),$(MAKECMDGOALS)),) 79 check_feat := 0 80endif 81endif 82 83ifeq ($(check_feat),1) 84ifeq ($(FEATURES_DUMP),) 85include $(srctree)/tools/build/Makefile.feature 86else 87include $(FEATURES_DUMP) 88endif 89endif 90 91export prefix libdir src obj 92 93# Shell quotes 94libdir_SQ = $(subst ','\'',$(libdir)) 95libdir_relative_SQ = $(subst ','\'',$(libdir_relative)) 96 97LIB_FILE = libbpf.a libbpf.so 98 99VERSION = $(BPF_VERSION) 100PATCHLEVEL = $(BPF_PATCHLEVEL) 101EXTRAVERSION = $(BPF_EXTRAVERSION) 102 103OBJ = $@ 104N = 105 106LIBBPF_VERSION = $(BPF_VERSION).$(BPF_PATCHLEVEL).$(BPF_EXTRAVERSION) 107 108# Set compile option CFLAGS 109ifdef EXTRA_CFLAGS 110 CFLAGS := $(EXTRA_CFLAGS) 111else 112 CFLAGS := -g -Wall 113endif 114 115ifeq ($(feature-libelf-mmap), 1) 116 override CFLAGS += -DHAVE_LIBELF_MMAP_SUPPORT 117endif 118 119ifeq ($(feature-reallocarray), 0) 120 override CFLAGS += -DCOMPAT_NEED_REALLOCARRAY 121endif 122 123# Append required CFLAGS 124override CFLAGS += $(EXTRA_WARNINGS) 125override CFLAGS += -Werror -Wall 126override CFLAGS += -fPIC 127override CFLAGS += $(INCLUDES) 128override CFLAGS += -fvisibility=hidden 129 130ifeq ($(VERBOSE),1) 131 Q = 132else 133 Q = @ 134endif 135 136# Disable command line variables (CFLAGS) override from top 137# level Makefile (perf), otherwise build Makefile will get 138# the same command line setup. 139MAKEOVERRIDES= 140 141all: 142 143export srctree OUTPUT CC LD CFLAGS V 144include $(srctree)/tools/build/Makefile.include 145 146BPF_IN := $(OUTPUT)libbpf-in.o 147LIB_FILE := $(addprefix $(OUTPUT),$(LIB_FILE)) 148VERSION_SCRIPT := libbpf.map 149 150GLOBAL_SYM_COUNT = $(shell readelf -s $(BPF_IN) | \ 151 awk '/GLOBAL/ && /DEFAULT/ && !/UND/ {s++} END{print s}') 152VERSIONED_SYM_COUNT = $(shell readelf -s $(OUTPUT)libbpf.so | \ 153 grep -Eo '[^ ]+@LIBBPF_' | cut -d@ -f1 | sort -u | wc -l) 154 155CMD_TARGETS = $(LIB_FILE) 156 157CXX_TEST_TARGET = $(OUTPUT)test_libbpf 158 159ifeq ($(feature-cxx), 1) 160 CMD_TARGETS += $(CXX_TEST_TARGET) 161endif 162 163TARGETS = $(CMD_TARGETS) 164 165all: fixdep all_cmd 166 167all_cmd: $(CMD_TARGETS) check 168 169$(BPF_IN): force elfdep bpfdep 170 @(test -f ../../include/uapi/linux/bpf.h -a -f ../../../include/uapi/linux/bpf.h && ( \ 171 (diff -B ../../include/uapi/linux/bpf.h ../../../include/uapi/linux/bpf.h >/dev/null) || \ 172 echo "Warning: Kernel ABI header at 'tools/include/uapi/linux/bpf.h' differs from latest version at 'include/uapi/linux/bpf.h'" >&2 )) || true 173 @(test -f ../../include/uapi/linux/bpf_common.h -a -f ../../../include/uapi/linux/bpf_common.h && ( \ 174 (diff -B ../../include/uapi/linux/bpf_common.h ../../../include/uapi/linux/bpf_common.h >/dev/null) || \ 175 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 176 @(test -f ../../include/uapi/linux/netlink.h -a -f ../../../include/uapi/linux/netlink.h && ( \ 177 (diff -B ../../include/uapi/linux/netlink.h ../../../include/uapi/linux/netlink.h >/dev/null) || \ 178 echo "Warning: Kernel ABI header at 'tools/include/uapi/linux/netlink.h' differs from latest version at 'include/uapi/linux/netlink.h'" >&2 )) || true 179 @(test -f ../../include/uapi/linux/if_link.h -a -f ../../../include/uapi/linux/if_link.h && ( \ 180 (diff -B ../../include/uapi/linux/if_link.h ../../../include/uapi/linux/if_link.h >/dev/null) || \ 181 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 182 $(Q)$(MAKE) $(build)=libbpf 183 184$(OUTPUT)libbpf.so: $(BPF_IN) 185 $(QUIET_LINK)$(CC) --shared -Wl,--version-script=$(VERSION_SCRIPT) \ 186 $^ -o $@ 187 188$(OUTPUT)libbpf.a: $(BPF_IN) 189 $(QUIET_LINK)$(RM) $@; $(AR) rcs $@ $^ 190 191$(OUTPUT)test_libbpf: test_libbpf.cpp $(OUTPUT)libbpf.a 192 $(QUIET_LINK)$(CXX) $^ -lelf -o $@ 193 194check: check_abi 195 196check_abi: $(OUTPUT)libbpf.so 197 @if [ "$(GLOBAL_SYM_COUNT)" != "$(VERSIONED_SYM_COUNT)" ]; then \ 198 echo "Warning: Num of global symbols in $(BPF_IN)" \ 199 "($(GLOBAL_SYM_COUNT)) does NOT match with num of" \ 200 "versioned symbols in $^ ($(VERSIONED_SYM_COUNT))." \ 201 "Please make sure all LIBBPF_API symbols are" \ 202 "versioned in $(VERSION_SCRIPT)." >&2; \ 203 exit 1; \ 204 fi 205 206define do_install 207 if [ ! -d '$(DESTDIR_SQ)$2' ]; then \ 208 $(INSTALL) -d -m 755 '$(DESTDIR_SQ)$2'; \ 209 fi; \ 210 $(INSTALL) $1 $(if $3,-m $3,) '$(DESTDIR_SQ)$2' 211endef 212 213install_lib: all_cmd 214 $(call QUIET_INSTALL, $(LIB_FILE)) \ 215 $(call do_install,$(LIB_FILE),$(libdir_SQ)) 216 217install_headers: 218 $(call QUIET_INSTALL, headers) \ 219 $(call do_install,bpf.h,$(prefix)/include/bpf,644); \ 220 $(call do_install,libbpf.h,$(prefix)/include/bpf,644); 221 $(call do_install,btf.h,$(prefix)/include/bpf,644); 222 223install: install_lib 224 225### Cleaning rules 226 227config-clean: 228 $(call QUIET_CLEAN, config) 229 $(Q)$(MAKE) -C $(srctree)/tools/build/feature/ clean >/dev/null 230 231clean: 232 $(call QUIET_CLEAN, libbpf) $(RM) $(TARGETS) $(CXX_TEST_TARGET) \ 233 *.o *~ *.a *.so .*.d .*.cmd LIBBPF-CFLAGS 234 $(call QUIET_CLEAN, core-gen) $(RM) $(OUTPUT)FEATURE-DUMP.libbpf 235 236 237 238PHONY += force elfdep bpfdep 239force: 240 241elfdep: 242 @if [ "$(feature-libelf)" != "1" ]; then echo "No libelf found"; exit 1 ; fi 243 244bpfdep: 245 @if [ "$(feature-bpf)" != "1" ]; then echo "BPF API too old"; exit 1 ; fi 246 247# Declare the contents of the .PHONY variable as phony. We keep that 248# information in a variable so we can use it in if_changed and friends. 249.PHONY: $(PHONY) 250