tools/lib/bpf/Makefile

   1 # SPDX-License-Identifier: GPL-2.0
   2 # Most of this file is copied from tools/lib/traceevent/Makefile
   3
   4 BPF_VERSION = 0
   5 BPF_PATCHLEVEL = 0
   6 BPF_EXTRAVERSION = 1
   7
   8 MAKEFLAGS += --no-print-directory
   9
  10 ifeq ($(srctree),)
  11 srctree := $(patsubst %/,%,$(dir $(CURDIR)))
  12 srctree := $(patsubst %/,%,$(dir $(srctree)))
  13 srctree := $(patsubst %/,%,$(dir $(srctree)))
  14 #$(info Determined 'srctree' to be $(srctree))
  15 endif
  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.
  22 define allow-override
  23   $(if $(or $(findstring environment,$(origin $(1))),\
  24             $(findstring command line,$(origin $(1)))),,\
  25     $(eval $(1) = $(2)))
  26 endef
  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
  32 INSTALL = 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.
  38 DESTDIR ?=
  39 DESTDIR_SQ = '$(subst ','\'',$(DESTDIR))'
  40
  41 include $(srctree)/tools/scripts/Makefile.arch
  42
  43 ifeq ($(LP64), 1)
  44   libdir_relative = lib64
  45 else
  46   libdir_relative = lib
  47 endif
  48
  49 prefix ?= /usr/local
  50 libdir = $(prefix)/$(libdir_relative)
  51 man_dir = $(prefix)/share/man
  52 man_dir_SQ = '$(subst ','\'',$(man_dir))'
  53
  54 export man_dir man_dir_SQ INSTALL
  55 export DESTDIR DESTDIR_SQ
  56
  57 include ../../scripts/Makefile.include
  58
  59 # copy a bit from Linux kbuild
  60
  61 ifeq ("$(origin V)", "command line")
  62   VERBOSE = $(V)
  63 endif
  64 ifndef VERBOSE
  65   VERBOSE = 0
  66 endif
  67
  68 FEATURE_USER = .libbpf
  69 FEATURE_TESTS = libelf libelf-getphdrnum libelf-mmap bpf
  70 FEATURE_DISPLAY = libelf bpf
  71
  72 INCLUDES = -I. -I$(srctree)/tools/include -I$(srctree)/tools/arch/$(ARCH)/include/uapi -I$(srctree)/tools/include/uapi
  73 FEATURE_CHECK_CFLAGS-bpf = $(INCLUDES)
  74
  75 check_feat := 1
  76 NON_CHECK_FEAT_TARGETS := clean TAGS tags cscope help
  77 ifdef MAKECMDGOALS
  78 ifeq ($(filter-out $(NON_CHECK_FEAT_TARGETS),$(MAKECMDGOALS)),)
  79   check_feat := 0
  80 endif
  81 endif
  82
  83 ifeq ($(check_feat),1)
  84 ifeq ($(FEATURES_DUMP),)
  85 include $(srctree)/tools/build/Makefile.feature
  86 else
  87 include $(FEATURES_DUMP)
  88 endif
  89 endif
  90
  91 export prefix libdir src obj
  92
  93 # Shell quotes
  94 libdir_SQ = $(subst ','\'',$(libdir))
  95 libdir_relative_SQ = $(subst ','\'',$(libdir_relative))
  96 plugin_dir_SQ = $(subst ','\'',$(plugin_dir))
  97
  98 LIB_FILE = libbpf.a libbpf.so
  99
 100 VERSION         = $(BPF_VERSION)
 101 PATCHLEVEL      = $(BPF_PATCHLEVEL)
 102 EXTRAVERSION    = $(BPF_EXTRAVERSION)
 103
 104 OBJ             = $@
 105 N               =
 106
 107 LIBBPF_VERSION = $(BPF_VERSION).$(BPF_PATCHLEVEL).$(BPF_EXTRAVERSION)
 108
 109 # Set compile option CFLAGS
 110 ifdef EXTRA_CFLAGS
 111   CFLAGS := $(EXTRA_CFLAGS)
 112 else
 113   CFLAGS := -g -Wall
 114 endif
 115
 116 ifeq ($(feature-libelf-mmap), 1)
 117   override CFLAGS += -DHAVE_LIBELF_MMAP_SUPPORT
 118 endif
 119
 120 ifeq ($(feature-libelf-getphdrnum), 1)
 121   override CFLAGS += -DHAVE_ELF_GETPHDRNUM_SUPPORT
 122 endif
 123
 124 # Append required CFLAGS
 125 override CFLAGS += $(EXTRA_WARNINGS)
 126 override CFLAGS += -Werror -Wall
 127 override CFLAGS += -fPIC
 128 override CFLAGS += $(INCLUDES)
 129
 130 ifeq ($(VERBOSE),1)
 131   Q =
 132 else
 133   Q = @
 134 endif
 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.
 139 MAKEOVERRIDES=
 140
 141 all:
 142
 143 export srctree OUTPUT CC LD CFLAGS V
 144 include $(srctree)/tools/build/Makefile.include
 145
 146 BPF_IN    := $(OUTPUT)libbpf-in.o
 147 LIB_FILE := $(addprefix $(OUTPUT),$(LIB_FILE))
 148
 149 CMD_TARGETS = $(LIB_FILE)
 150
 151 TARGETS = $(CMD_TARGETS)
 152
 153 all: fixdep $(VERSION_FILES) all_cmd
 154
 155 all_cmd: $(CMD_TARGETS)
 156
 157 $(BPF_IN): force elfdep bpfdep
 158         @(test -f ../../include/uapi/linux/bpf.h -a -f ../../../include/uapi/linux/bpf.h && ( \
 159         (diff -B ../../include/uapi/linux/bpf.h ../../../include/uapi/linux/bpf.h >/dev/null) || \
 160         echo "Warning: Kernel ABI header at 'tools/include/uapi/linux/bpf.h' differs from latest version at 'include/uapi/linux/bpf.h'" >&2 )) || true
 161         @(test -f ../../include/uapi/linux/bpf_common.h -a -f ../../../include/uapi/linux/bpf_common.h && ( \
 162         (diff -B ../../include/uapi/linux/bpf_common.h ../../../include/uapi/linux/bpf_common.h >/dev/null) || \
 163         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
 164         $(Q)$(MAKE) $(build)=libbpf
 165
 166 $(OUTPUT)libbpf.so: $(BPF_IN)
 167         $(QUIET_LINK)$(CC) --shared $^ -o $@
 168
 169 $(OUTPUT)libbpf.a: $(BPF_IN)
 170         $(QUIET_LINK)$(RM) $@; $(AR) rcs $@ $^
 171
 172 define update_dir
 173   (echo $1 > $@.tmp;                            \
 174    if [ -r $@ ] && cmp -s $@ $@.tmp; then       \
 175      rm -f $@.tmp;                              \
 176    else                                         \
 177      echo '  UPDATE                 $@';        \
 178      mv -f $@.tmp $@;                           \
 179    fi);
 180 endef
 181
 182 define do_install
 183         if [ ! -d '$(DESTDIR_SQ)$2' ]; then             \
 184                 $(INSTALL) -d -m 755 '$(DESTDIR_SQ)$2'; \
 185         fi;                                             \
 186         $(INSTALL) $1 '$(DESTDIR_SQ)$2'
 187 endef
 188
 189 install_lib: all_cmd
 190         $(call QUIET_INSTALL, $(LIB_FILE)) \
 191                 $(call do_install,$(LIB_FILE),$(libdir_SQ))
 192
 193 install_headers:
 194         $(call QUIET_INSTALL, headers) \
 195                 $(call do_install,bpf.h,$(prefix)/include/bpf,644)
 196
 197 install: install_lib
 198
 199 ### Cleaning rules
 200
 201 config-clean:
 202         $(call QUIET_CLEAN, config)
 203         $(Q)$(MAKE) -C $(srctree)/tools/build/feature/ clean >/dev/null
 204
 205 clean:
 206         $(call QUIET_CLEAN, libbpf) $(RM) *.o *~ $(TARGETS) *.a *.so $(VERSION_FILES) .*.d .*.cmd \
 207                 $(RM) LIBBPF-CFLAGS
 208         $(call QUIET_CLEAN, core-gen) $(RM) $(OUTPUT)FEATURE-DUMP.libbpf
 209
 210
 211
 212 PHONY += force elfdep bpfdep
 213 force:
 214
 215 elfdep:
 216         @if [ "$(feature-libelf)" != "1" ]; then echo "No libelf found"; exit -1 ; fi
 217
 218 bpfdep:
 219         @if [ "$(feature-bpf)" != "1" ]; then echo "BPF API too old"; exit -1 ; fi
 220
 221 # Declare the contents of the .PHONY variable as phony.  We keep that
 222 # information in a variable so we can use it in if_changed and friends.
 223 .PHONY: $(PHONY)