libbpf: Make libbpf_version.h non-auto-generated

Turn previously auto-generated libbpf_version.h header into a normal
header file. This prevents various tricky Makefile integration issues,
simplifies the overall build process, but also allows to further extend
it with some more versioning-related APIs in the future.

To prevent accidental out-of-sync versions as defined by libbpf.map and
libbpf_version.h, Makefile checks their consistency at build time.

Simultaneously with this change bump libbpf.map to v0.6.

Also undo adding libbpf's output directory into include path for
kernel/bpf/preload, bpftool, and resolve_btfids, which is not necessary
because libbpf_version.h is just a normal header like any other.

Fixes: 0b46b75505 ("libbpf: Add LIBBPF_DEPRECATED_SINCE macro for scheduling API deprecations")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210913222309.3220849-1-andrii@kernel.org
This commit is contained in:
Andrii Nakryiko 2021-09-13 15:23:09 -07:00 committed by Alexei Starovoitov
parent dbd7eb14e0
commit 2f38304127
7 changed files with 35 additions and 20 deletions

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@ -10,15 +10,12 @@ LIBBPF_OUT = $(abspath $(obj))
$(LIBBPF_A):
$(Q)$(MAKE) -C $(LIBBPF_SRCS) O=$(LIBBPF_OUT)/ OUTPUT=$(LIBBPF_OUT)/ $(LIBBPF_OUT)/libbpf.a
userccflags += -I$(LIBBPF_OUT) -I $(srctree)/tools/include/ \
-I $(srctree)/tools/include/uapi \
userccflags += -I $(srctree)/tools/include/ -I $(srctree)/tools/include/uapi \
-I $(srctree)/tools/lib/ -Wno-unused-result
userprogs := bpf_preload_umd
clean-files := $(userprogs) libbpf_version.h bpf_helper_defs.h FEATURE-DUMP.libbpf staticobjs/ feature/
$(obj)/iterators/iterators.o: $(LIBBPF_A)
clean-files := $(userprogs) bpf_helper_defs.h FEATURE-DUMP.libbpf staticobjs/ feature/
bpf_preload_umd-objs := iterators/iterators.o
bpf_preload_umd-userldlibs := $(LIBBPF_A) -lelf -lz

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@ -60,7 +60,6 @@ CFLAGS += -W -Wall -Wextra -Wno-unused-parameter -Wno-missing-field-initializers
CFLAGS += $(filter-out -Wswitch-enum -Wnested-externs,$(EXTRA_WARNINGS))
CFLAGS += -DPACKAGE='"bpftool"' -D__EXPORTED_HEADERS__ \
-I$(if $(OUTPUT),$(OUTPUT),.) \
$(if $(LIBBPF_OUTPUT),-I$(LIBBPF_OUTPUT)) \
-I$(srctree)/kernel/bpf/ \
-I$(srctree)/tools/include \
-I$(srctree)/tools/include/uapi \

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@ -47,7 +47,6 @@ $(BPFOBJ): $(wildcard $(LIBBPF_SRC)/*.[ch] $(LIBBPF_SRC)/Makefile) | $(OUTPUT)/l
CFLAGS := -g \
-I$(srctree)/tools/include \
-I$(srctree)/tools/include/uapi \
-I$(LIBBPF_OUT) \
-I$(LIBBPF_SRC) \
-I$(SUBCMD_SRC)

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@ -1,5 +1,4 @@
# SPDX-License-Identifier: GPL-2.0-only
libbpf_version.h
libbpf.pc
libbpf.so.*
TAGS

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@ -113,9 +113,8 @@ SHARED_OBJDIR := $(OUTPUT)sharedobjs/
STATIC_OBJDIR := $(OUTPUT)staticobjs/
BPF_IN_SHARED := $(SHARED_OBJDIR)libbpf-in.o
BPF_IN_STATIC := $(STATIC_OBJDIR)libbpf-in.o
VERSION_HDR := $(OUTPUT)libbpf_version.h
BPF_HELPER_DEFS := $(OUTPUT)bpf_helper_defs.h
BPF_GENERATED := $(BPF_HELPER_DEFS) $(VERSION_HDR)
BPF_GENERATED := $(BPF_HELPER_DEFS)
LIB_TARGET := $(addprefix $(OUTPUT),$(LIB_TARGET))
LIB_FILE := $(addprefix $(OUTPUT),$(LIB_FILE))
@ -165,12 +164,6 @@ $(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)
$(VERSION_HDR): force
$(QUIET_GEN)echo "/* This file was auto-generated. */" > $@
@echo "" >> $@
@echo "#define LIBBPF_MAJOR_VERSION $(LIBBPF_MAJOR_VERSION)" >> $@
@echo "#define LIBBPF_MINOR_VERSION $(LIBBPF_MINOR_VERSION)" >> $@
$(OUTPUT)libbpf.so: $(OUTPUT)libbpf.so.$(LIBBPF_VERSION)
$(OUTPUT)libbpf.so.$(LIBBPF_VERSION): $(BPF_IN_SHARED) $(VERSION_SCRIPT)
@ -189,7 +182,7 @@ $(OUTPUT)libbpf.pc:
-e "s|@VERSION@|$(LIBBPF_VERSION)|" \
< libbpf.pc.template > $@
check: check_abi
check: check_abi check_version
check_abi: $(OUTPUT)libbpf.so $(VERSION_SCRIPT)
@if [ "$(GLOBAL_SYM_COUNT)" != "$(VERSIONED_SYM_COUNT)" ]; then \
@ -215,6 +208,21 @@ check_abi: $(OUTPUT)libbpf.so $(VERSION_SCRIPT)
exit 1; \
fi
HDR_MAJ_VERSION := $(shell grep -oE '^\#define LIBBPF_MAJOR_VERSION ([0-9]+)$$' libbpf_version.h | cut -d' ' -f3)
HDR_MIN_VERSION := $(shell grep -oE '^\#define LIBBPF_MINOR_VERSION ([0-9]+)$$' 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'; \
@ -234,8 +242,9 @@ install_lib: all_cmd
cp -fpR $(LIB_FILE) $(DESTDIR)$(libdir_SQ)
INSTALL_HEADERS = bpf.h libbpf.h btf.h libbpf_common.h libbpf_legacy.h xsk.h \
bpf_helpers.h $(BPF_GENERATED) bpf_tracing.h \
bpf_endian.h bpf_core_read.h skel_internal.h
bpf_helpers.h $(BPF_GENERATED) bpf_tracing.h \
bpf_endian.h bpf_core_read.h skel_internal.h \
libbpf_version.h
install_headers: $(BPF_GENERATED)
$(call QUIET_INSTALL, headers) \
@ -255,7 +264,7 @@ clean:
$(addprefix $(OUTPUT), \
*.o *.a *.so *.so.$(LIBBPF_MAJOR_VERSION) *.pc)
PHONY += force cscope tags
PHONY += force cscope tags check check_abi check_version
force:
cscope:

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@ -386,3 +386,6 @@ LIBBPF_0.5.0 {
btf_dump__dump_type_data;
libbpf_set_strict_mode;
} LIBBPF_0.4.0;
LIBBPF_0.6.0 {
} LIBBPF_0.5.0;

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@ -0,0 +1,9 @@
/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
/* Copyright (C) 2021 Facebook */
#ifndef __LIBBPF_VERSION_H
#define __LIBBPF_VERSION_H
#define LIBBPF_MAJOR_VERSION 0
#define LIBBPF_MINOR_VERSION 6
#endif /* __LIBBPF_VERSION_H */