1# Most of this file is copied from tools/lib/traceevent/Makefile
  2
  3BPF_VERSION = 0
  4BPF_PATCHLEVEL = 0
  5BPF_EXTRAVERSION = 1
  6
  7MAKEFLAGS += --no-print-directory
  8
  9ifeq ($(srctree),)
 10srctree := $(patsubst %/,%,$(dir $(CURDIR)))
 11srctree := $(patsubst %/,%,$(dir $(srctree)))
 12srctree := $(patsubst %/,%,$(dir $(srctree)))
 13#$(info Determined 'srctree' to be $(srctree))
 14endif
 15
 16# Makefiles suck: This macro sets a default value of $(2) for the
 17# variable named by $(1), unless the variable has been set by
 18# environment or command line. This is necessary for CC and AR
 19# because make sets default values, so the simpler ?= approach
 20# won't work as expected.
 21define allow-override
 22  $(if $(or $(findstring environment,$(origin $(1))),\
 23            $(findstring command line,$(origin $(1)))),,\
 24    $(eval $(1) = $(2)))
 25endef
 26
 27# Allow setting CC and AR, or setting CROSS_COMPILE as a prefix.
 28$(call allow-override,CC,$(CROSS_COMPILE)gcc)
 29$(call allow-override,AR,$(CROSS_COMPILE)ar)
 30
 31INSTALL = install
 32
 33# Use DESTDIR for installing into a different root directory.
 34# This is useful for building a package. The program will be
 35# installed in this directory as if it was the root directory.
 36# Then the build tool can move it later.
 37DESTDIR ?=
 38DESTDIR_SQ = '$(subst ','\'',$(DESTDIR))'
 39
 40include $(srctree)/tools/scripts/Makefile.arch
 41
 42ifeq ($(LP64), 1)
 43  libdir_relative = lib64
 44else
 45  libdir_relative = lib
 46endif
 47
 48prefix ?= /usr/local
 49libdir = $(prefix)/$(libdir_relative)
 50man_dir = $(prefix)/share/man
 51man_dir_SQ = '$(subst ','\'',$(man_dir))'
 52
 53export man_dir man_dir_SQ INSTALL
 54export DESTDIR DESTDIR_SQ
 55
 56include ../../scripts/Makefile.include
 57
 58# copy a bit from Linux kbuild
 59
 60ifeq ("$(origin V)", "command line")
 61  VERBOSE = $(V)
 62endif
 63ifndef VERBOSE
 64  VERBOSE = 0
 65endif
 66
 67FEATURE_USER = .libbpf
 68FEATURE_TESTS = libelf libelf-getphdrnum libelf-mmap bpf
 69FEATURE_DISPLAY = libelf bpf
 70
 71INCLUDES = -I. -I$(srctree)/tools/include -I$(srctree)/tools/arch/$(ARCH)/include/uapi -I$(srctree)/tools/include/uapi
 72FEATURE_CHECK_CFLAGS-bpf = $(INCLUDES)
 73
 74check_feat := 1
 75NON_CHECK_FEAT_TARGETS := clean TAGS tags cscope help
 76ifdef MAKECMDGOALS
 77ifeq ($(filter-out $(NON_CHECK_FEAT_TARGETS),$(MAKECMDGOALS)),)
 78  check_feat := 0
 79endif
 80endif
 81
 82ifeq ($(check_feat),1)
 83ifeq ($(FEATURES_DUMP),)
 84include $(srctree)/tools/build/Makefile.feature
 85else
 86include $(FEATURES_DUMP)
 87endif
 88endif
 89
 90export prefix libdir src obj
 91
 92# Shell quotes
 93libdir_SQ = $(subst ','\'',$(libdir))
 94libdir_relative_SQ = $(subst ','\'',$(libdir_relative))
 95plugin_dir_SQ = $(subst ','\'',$(plugin_dir))
 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-libelf-getphdrnum), 1)
120  override CFLAGS += -DHAVE_ELF_GETPHDRNUM_SUPPORT
121endif
122
123# Append required CFLAGS
124override CFLAGS += $(EXTRA_WARNINGS)
125override CFLAGS += -Werror -Wall
126override CFLAGS += -fPIC
127override CFLAGS += $(INCLUDES)
128
129ifeq ($(VERBOSE),1)
130  Q =
131else
132  Q = @
133endif
134
135# Disable command line variables (CFLAGS) overide from top
136# level Makefile (perf), otherwise build Makefile will get
137# the same command line setup.
138MAKEOVERRIDES=
139
140all:
141
142export srctree OUTPUT CC LD CFLAGS V
143include $(srctree)/tools/build/Makefile.include
144
145BPF_IN    := $(OUTPUT)libbpf-in.o
146LIB_FILE := $(addprefix $(OUTPUT),$(LIB_FILE))
147
148CMD_TARGETS = $(LIB_FILE)
149
150TARGETS = $(CMD_TARGETS)
151
152all: fixdep $(VERSION_FILES) all_cmd
153
154all_cmd: $(CMD_TARGETS)
155
156$(BPF_IN): force elfdep bpfdep
157	@(test -f ../../../include/uapi/linux/bpf.h -a -f ../../../include/uapi/linux/bpf.h && ( \
158	(diff -B ../../include/uapi/linux/bpf.h ../../../include/uapi/linux/bpf.h >/dev/null) || \
159	echo "Warning: tools/include/uapi/linux/bpf.h differs from kernel" >&2 )) || true
160	@(test -f ../../../include/uapi/linux/bpf_common.h -a -f ../../../include/uapi/linux/bpf_common.h && ( \
161	(diff -B ../../include/uapi/linux/bpf_common.h ../../../include/uapi/linux/bpf_common.h >/dev/null) || \
162	echo "Warning: tools/include/uapi/linux/bpf_common.h differs from kernel" >&2 )) || true
163	$(Q)$(MAKE) $(build)=libbpf
164
165$(OUTPUT)libbpf.so: $(BPF_IN)
166	$(QUIET_LINK)$(CC) --shared $^ -o $@
167
168$(OUTPUT)libbpf.a: $(BPF_IN)
169	$(QUIET_LINK)$(RM) $@; $(AR) rcs $@ $^
170
171define update_dir
172  (echo $1 > $@.tmp;				\
173   if [ -r $@ ] && cmp -s $@ $@.tmp; then	\
174     rm -f $@.tmp;				\
175   else						\
176     echo '  UPDATE                 $@';	\
177     mv -f $@.tmp $@;				\
178   fi);
179endef
180
181define do_install
182	if [ ! -d '$(DESTDIR_SQ)$2' ]; then		\
183		$(INSTALL) -d -m 755 '$(DESTDIR_SQ)$2';	\
184	fi;						\
185	$(INSTALL) $1 '$(DESTDIR_SQ)$2'
186endef
187
188install_lib: all_cmd
189	$(call QUIET_INSTALL, $(LIB_FILE)) \
190		$(call do_install,$(LIB_FILE),$(libdir_SQ))
191
192install: install_lib
193
194### Cleaning rules
195
196config-clean:
197	$(call QUIET_CLEAN, config)
198	$(Q)$(MAKE) -C $(srctree)/tools/build/feature/ clean >/dev/null
199
200clean:
201	$(call QUIET_CLEAN, libbpf) $(RM) *.o *~ $(TARGETS) *.a *.so $(VERSION_FILES) .*.d .*.cmd \
202		$(RM) LIBBPF-CFLAGS
203	$(call QUIET_CLEAN, core-gen) $(RM) $(OUTPUT)FEATURE-DUMP.libbpf
204
205
206
207PHONY += force elfdep bpfdep
208force:
209
210elfdep:
211	@if [ "$(feature-libelf)" != "1" ]; then echo "No libelf found"; exit -1 ; fi
212
213bpfdep:
214	@if [ "$(feature-bpf)" != "1" ]; then echo "BPF API too old"; exit -1 ; fi
215
216# Declare the contents of the .PHONY variable as phony.  We keep that
217# information in a variable so we can use it in if_changed and friends.
218.PHONY: $(PHONY)