summaryrefslogtreecommitdiffstats
path: root/tools/bpf
diff options
context:
space:
mode:
authorQuentin Monnet <quentin@isovalent.com>2021-09-08 14:32:26 -0700
committerDaniel Borkmann <daniel@iogearbox.net>2021-09-09 23:28:05 +0200
commit0b46b755056043dccfe078b96b256502b88f2464 (patch)
treedb9e0fd756e5dae38b0a58f9961d0ccef8c7bafe /tools/bpf
parent006a5099fc18a43792b01d002e1e45c5541ea666 (diff)
downloadlinux-0b46b755056043dccfe078b96b256502b88f2464.tar.bz2
libbpf: Add LIBBPF_DEPRECATED_SINCE macro for scheduling API deprecations
Introduce a macro LIBBPF_DEPRECATED_SINCE(major, minor, message) to prepare the deprecation of two API functions. This macro marks functions as deprecated when libbpf's version reaches the values passed as an argument. As part of this change libbpf_version.h header is added with recorded major (LIBBPF_MAJOR_VERSION) and minor (LIBBPF_MINOR_VERSION) libbpf version macros. They are now part of libbpf public API and can be relied upon by user code. libbpf_version.h is installed system-wide along other libbpf public headers. Due to this new build-time auto-generated header, in-kernel applications relying on libbpf (resolve_btfids, bpftool, bpf_preload) are updated to include libbpf's output directory as part of a list of include search paths. Better fix would be to use libbpf's make_install target to install public API headers, but that clean up is left out as a future improvement. The build changes were tested by building kernel (with KBUILD_OUTPUT and O= specified explicitly), bpftool, libbpf, selftests/bpf, and resolve_btfids builds. No problems were detected. Note that because of the constraints of the C preprocessor we have to write a few lines of macro magic for each version used to prepare deprecation (0.6 for now). Also, use LIBBPF_DEPRECATED_SINCE() to schedule deprecation of btf__get_from_id() and btf__load(), which are replaced by btf__load_from_kernel_by_id() and btf__load_into_kernel(), respectively, starting from future libbpf v0.6. This is part of libbpf 1.0 effort ([0]). [0] Closes: https://github.com/libbpf/libbpf/issues/278 Co-developed-by: Quentin Monnet <quentin@isovalent.com> Co-developed-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Quentin Monnet <quentin@isovalent.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20210908213226.1871016-1-andrii@kernel.org
Diffstat (limited to 'tools/bpf')
-rw-r--r--tools/bpf/bpftool/Makefile4
-rw-r--r--tools/bpf/resolve_btfids/Makefile6
2 files changed, 8 insertions, 2 deletions
diff --git a/tools/bpf/bpftool/Makefile b/tools/bpf/bpftool/Makefile
index d73232be1e99..06aa1616dabe 100644
--- a/tools/bpf/bpftool/Makefile
+++ b/tools/bpf/bpftool/Makefile
@@ -60,6 +60,7 @@ 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 \
@@ -137,7 +138,10 @@ endif
BPFTOOL_BOOTSTRAP := $(BOOTSTRAP_OUTPUT)bpftool
BOOTSTRAP_OBJS = $(addprefix $(BOOTSTRAP_OUTPUT),main.o common.o json_writer.o gen.o btf.o xlated_dumper.o btf_dumper.o disasm.o)
+$(BOOTSTRAP_OBJS): $(LIBBPF_BOOTSTRAP)
+
OBJS = $(patsubst %.c,$(OUTPUT)%.o,$(SRCS)) $(OUTPUT)disasm.o
+$(OBJS): $(LIBBPF)
VMLINUX_BTF_PATHS ?= $(if $(O),$(O)/vmlinux) \
$(if $(KBUILD_OUTPUT),$(KBUILD_OUTPUT)/vmlinux) \
diff --git a/tools/bpf/resolve_btfids/Makefile b/tools/bpf/resolve_btfids/Makefile
index bb9fa8de7e62..edc0c329cf74 100644
--- a/tools/bpf/resolve_btfids/Makefile
+++ b/tools/bpf/resolve_btfids/Makefile
@@ -26,6 +26,7 @@ LIBBPF_SRC := $(srctree)/tools/lib/bpf/
SUBCMD_SRC := $(srctree)/tools/lib/subcmd/
BPFOBJ := $(OUTPUT)/libbpf/libbpf.a
+LIBBPF_OUT := $(abspath $(dir $(BPFOBJ)))/
SUBCMDOBJ := $(OUTPUT)/libsubcmd/libsubcmd.a
BINARY := $(OUTPUT)/resolve_btfids
@@ -41,11 +42,12 @@ $(SUBCMDOBJ): fixdep FORCE | $(OUTPUT)/libsubcmd
$(Q)$(MAKE) -C $(SUBCMD_SRC) OUTPUT=$(abspath $(dir $@))/ $(abspath $@)
$(BPFOBJ): $(wildcard $(LIBBPF_SRC)/*.[ch] $(LIBBPF_SRC)/Makefile) | $(OUTPUT)/libbpf
- $(Q)$(MAKE) $(submake_extras) -C $(LIBBPF_SRC) OUTPUT=$(abspath $(dir $@))/ $(abspath $@)
+ $(Q)$(MAKE) $(submake_extras) -C $(LIBBPF_SRC) OUTPUT=$(LIBBPF_OUT) $(abspath $@)
CFLAGS := -g \
-I$(srctree)/tools/include \
-I$(srctree)/tools/include/uapi \
+ -I$(LIBBPF_OUT) \
-I$(LIBBPF_SRC) \
-I$(SUBCMD_SRC)
@@ -54,7 +56,7 @@ LIBS = -lelf -lz
export srctree OUTPUT CFLAGS Q
include $(srctree)/tools/build/Makefile.include
-$(BINARY_IN): fixdep FORCE | $(OUTPUT)
+$(BINARY_IN): $(BPFOBJ) fixdep FORCE | $(OUTPUT)
$(Q)$(MAKE) $(build)=resolve_btfids
$(BINARY): $(BPFOBJ) $(SUBCMDOBJ) $(BINARY_IN)