linux/tools/lib/bpf/Makefile
Kumar Kartikeya Dwivedi 3a74ac2d11 libbpf: Compile using -std=gnu89
The minimum supported C standard version is C89, with use of GNU
extensions, hence make sure to catch any instances that would break
the build for this mode by passing -std=gnu89.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211105234243.390179-4-memxor@gmail.com
2021-11-09 13:27:52 -08:00

288 lines
9.7 KiB
Makefile

# SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
# Most of this file is copied from tools/lib/traceevent/Makefile
RM ?= rm
srctree = $(abs_srctree)
VERSION_SCRIPT := libbpf.map
LIBBPF_VERSION := $(shell \
grep -oE '^LIBBPF_([0-9.]+)' $(VERSION_SCRIPT) | \
sort -rV | head -n1 | cut -d'_' -f2)
LIBBPF_MAJOR_VERSION := $(word 1,$(subst ., ,$(LIBBPF_VERSION)))
LIBBPF_MINOR_VERSION := $(word 2,$(subst ., ,$(LIBBPF_VERSION)))
MAKEFLAGS += --no-print-directory
# This will work when bpf is built in tools env. where srctree
# isn't set and when invoked from selftests build, where srctree
# is a ".". building_out_of_srctree is undefined for in srctree
# builds
ifndef building_out_of_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 = $(V)
endif
ifndef VERBOSE
VERBOSE = 0
endif
INCLUDES = -I$(if $(OUTPUT),$(OUTPUT),.) \
-I$(srctree)/tools/include -I$(srctree)/tools/include/uapi
export prefix libdir src obj
# Shell quotes
libdir_SQ = $(subst ','\'',$(libdir))
libdir_relative_SQ = $(subst ','\'',$(libdir_relative))
OBJ = $@
N =
LIB_TARGET = libbpf.a libbpf.so.$(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 -O2
endif
# Append required CFLAGS
override CFLAGS += -std=gnu89
override CFLAGS += $(EXTRA_WARNINGS) -Wno-switch-enum
override CFLAGS += -Werror -Wall
override CFLAGS += $(INCLUDES)
override CFLAGS += -fvisibility=hidden
override CFLAGS += -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64
# flags specific for shared library
SHLIB_FLAGS := -DSHARED -fPIC
ifeq ($(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
SHARED_OBJDIR := $(OUTPUT)sharedobjs/
STATIC_OBJDIR := $(OUTPUT)staticobjs/
BPF_IN_SHARED := $(SHARED_OBJDIR)libbpf-in.o
BPF_IN_STATIC := $(STATIC_OBJDIR)libbpf-in.o
BPF_HELPER_DEFS := $(OUTPUT)bpf_helper_defs.h
BPF_GENERATED := $(BPF_HELPER_DEFS)
LIB_TARGET := $(addprefix $(OUTPUT),$(LIB_TARGET))
LIB_FILE := $(addprefix $(OUTPUT),$(LIB_FILE))
PC_FILE := $(addprefix $(OUTPUT),$(PC_FILE))
TAGS_PROG := $(if $(shell which etags 2>/dev/null),etags,ctags)
GLOBAL_SYM_COUNT = $(shell readelf -s --wide $(BPF_IN_SHARED) | \
cut -d "@" -f1 | sed 's/_v[0-9]_[0-9]_[0-9].*//' | \
sed 's/\[.*\]//' | \
awk '/GLOBAL/ && /DEFAULT/ && !/UND/ {print $$NF}' | \
sort -u | wc -l)
VERSIONED_SYM_COUNT = $(shell readelf --dyn-syms --wide $(OUTPUT)libbpf.so | \
sed 's/\[.*\]//' | \
awk '/GLOBAL/ && /DEFAULT/ && !/UND/ {print $$NF}' | \
grep -Eo '[^ ]+@LIBBPF_' | cut -d@ -f1 | sort -u | wc -l)
CMD_TARGETS = $(LIB_TARGET) $(PC_FILE)
all: fixdep
$(Q)$(MAKE) all_cmd
all_cmd: $(CMD_TARGETS) check
$(BPF_IN_SHARED): force $(BPF_GENERATED)
@(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/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) $(build)=libbpf OUTPUT=$(SHARED_OBJDIR) CFLAGS="$(CFLAGS) $(SHLIB_FLAGS)"
$(BPF_IN_STATIC): force $(BPF_GENERATED)
$(Q)$(MAKE) $(build)=libbpf OUTPUT=$(STATIC_OBJDIR)
$(BPF_HELPER_DEFS): $(srctree)/tools/include/uapi/linux/bpf.h
$(QUIET_GEN)$(srctree)/scripts/bpf_doc.py --header \
--file $(srctree)/tools/include/uapi/linux/bpf.h > $(BPF_HELPER_DEFS)
$(OUTPUT)libbpf.so: $(OUTPUT)libbpf.so.$(LIBBPF_VERSION)
$(OUTPUT)libbpf.so.$(LIBBPF_VERSION): $(BPF_IN_SHARED) $(VERSION_SCRIPT)
$(QUIET_LINK)$(CC) $(LDFLAGS) \
--shared -Wl,-soname,libbpf.so.$(LIBBPF_MAJOR_VERSION) \
-Wl,--version-script=$(VERSION_SCRIPT) $< -lelf -lz -o $@
@ln -sf $(@F) $(OUTPUT)libbpf.so
@ln -sf $(@F) $(OUTPUT)libbpf.so.$(LIBBPF_MAJOR_VERSION)
$(OUTPUT)libbpf.a: $(BPF_IN_STATIC)
$(QUIET_LINK)$(RM) -f $@; $(AR) rcs $@ $^
$(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_version
check_abi: $(OUTPUT)libbpf.so $(VERSION_SCRIPT)
@if [ "$(GLOBAL_SYM_COUNT)" != "$(VERSIONED_SYM_COUNT)" ]; then \
echo "Warning: Num of global symbols in $(BPF_IN_SHARED)" \
"($(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; \
readelf -s --wide $(BPF_IN_SHARED) | \
cut -d "@" -f1 | sed 's/_v[0-9]_[0-9]_[0-9].*//' | \
sed 's/\[.*\]//' | \
awk '/GLOBAL/ && /DEFAULT/ && !/UND/ {print $$NF}'| \
sort -u > $(OUTPUT)libbpf_global_syms.tmp; \
readelf --dyn-syms --wide $(OUTPUT)libbpf.so | \
sed 's/\[.*\]//' | \
awk '/GLOBAL/ && /DEFAULT/ && !/UND/ {print $$NF}'| \
grep -Eo '[^ ]+@LIBBPF_' | cut -d@ -f1 | \
sort -u > $(OUTPUT)libbpf_versioned_syms.tmp; \
diff -u $(OUTPUT)libbpf_global_syms.tmp \
$(OUTPUT)libbpf_versioned_syms.tmp; \
rm $(OUTPUT)libbpf_global_syms.tmp \
$(OUTPUT)libbpf_versioned_syms.tmp; \
exit 1; \
fi
HDR_MAJ_VERSION := $(shell grep -oE '^$(pound)define LIBBPF_MAJOR_VERSION ([0-9]+)$$' libbpf_version.h | cut -d' ' -f3)
HDR_MIN_VERSION := $(shell grep -oE '^$(pound)define LIBBPF_MINOR_VERSION ([0-9]+)$$' libbpf_version.h | cut -d' ' -f3)
check_version: $(VERSION_SCRIPT) libbpf_version.h
@if [ "$(HDR_MAJ_VERSION)" != "$(LIBBPF_MAJOR_VERSION)" ]; then \
echo "Error: libbpf major version mismatch detected: " \
"'$(HDR_MAJ_VERSION)' != '$(LIBBPF_MAJOR_VERSION)'" >&2; \
exit 1; \
fi
@if [ "$(HDR_MIN_VERSION)" != "$(LIBBPF_MINOR_VERSION)" ]; then \
echo "Error: libbpf minor version mismatch detected: " \
"'$(HDR_MIN_VERSION)' != '$(LIBBPF_MINOR_VERSION)'" >&2; \
exit 1; \
fi
define do_install_mkdir
if [ ! -d '$(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) $(if $3,-m $3,) $1 '$(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)
SRC_HDRS := bpf.h libbpf.h btf.h libbpf_common.h libbpf_legacy.h xsk.h \
bpf_helpers.h bpf_tracing.h bpf_endian.h bpf_core_read.h \
skel_internal.h libbpf_version.h
GEN_HDRS := $(BPF_GENERATED)
INSTALL_PFX := $(DESTDIR)$(prefix)/include/bpf
INSTALL_SRC_HDRS := $(addprefix $(INSTALL_PFX)/, $(SRC_HDRS))
INSTALL_GEN_HDRS := $(addprefix $(INSTALL_PFX)/, $(notdir $(GEN_HDRS)))
$(INSTALL_SRC_HDRS): $(INSTALL_PFX)/%.h: %.h
$(call QUIET_INSTALL, $@) \
$(call do_install,$<,$(prefix)/include/bpf,644)
$(INSTALL_GEN_HDRS): $(INSTALL_PFX)/%.h: $(OUTPUT)%.h
$(call QUIET_INSTALL, $@) \
$(call do_install,$<,$(prefix)/include/bpf,644)
install_headers: $(BPF_GENERATED) $(INSTALL_SRC_HDRS) $(INSTALL_GEN_HDRS)
install_pkgconfig: $(PC_FILE)
$(call QUIET_INSTALL, $(PC_FILE)) \
$(call do_install,$(PC_FILE),$(libdir_SQ)/pkgconfig,644)
install: install_lib install_pkgconfig install_headers
clean:
$(call QUIET_CLEAN, libbpf) $(RM) -rf $(CMD_TARGETS) \
*~ .*.d .*.cmd LIBBPF-CFLAGS $(BPF_GENERATED) \
$(SHARED_OBJDIR) $(STATIC_OBJDIR) \
$(addprefix $(OUTPUT), \
*.o *.a *.so *.so.$(LIBBPF_MAJOR_VERSION) *.pc)
PHONY += force cscope tags check check_abi check_version
force:
cscope:
ls *.c *.h > cscope.files
cscope -b -q -I $(srctree)/include -f cscope.out
tags:
$(RM) -f TAGS tags
ls *.c *.h | xargs $(TAGS_PROG) -a
# 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)
# Delete partially updated (corrupted) files on error
.DELETE_ON_ERROR: