Commit 1478994a authored by Quentin Monnet's avatar Quentin Monnet Committed by Andrii Nakryiko
Browse files

tools/resolve_btfids: Install libbpf headers when building 



API headers from libbpf should not be accessed directly from the
library's source directory. Instead, they should be exported with "make
install_headers". Let's make sure that resolve_btfids installs the
headers properly when building.

When descending from a parent Makefile, the specific output directories
for building the library and exporting the headers are configurable with
LIBBPF_OUT and LIBBPF_DESTDIR, respectively. This is in addition to
OUTPUT, on top of which those variables are constructed by default.

Also adjust the Makefile for the BPF selftests in order to point to the
(target) libbpf shared with other tools, instead of building a version
specific to resolve_btfids. Remove libbpf's order-only dependencies on
the include directories (they are created by libbpf and don't need to
exist beforehand).

Signed-off-by: default avatarQuentin Monnet <quentin@isovalent.com>
Signed-off-by: default avatarAndrii Nakryiko <andrii@kernel.org>
Acked-by: default avatarAndrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211007194438.34443-5-quentin@isovalent.com
parent f012ade1

tools/bpf/resolve_btfids/Makefile

+11 −5
Original line number Diff line number Diff line
@@ -29,25 +29,30 @@ BPFOBJ := $(OUTPUT)/libbpf/libbpf.a 
LIBBPF_OUT := $(abspath $(dir $(BPFOBJ)))/

SUBCMDOBJ  := $(OUTPUT)/libsubcmd/libsubcmd.a



LIBBPF_DESTDIR := $(LIBBPF_OUT)

LIBBPF_INCLUDE := $(LIBBPF_DESTDIR)include



BINARY     := $(OUTPUT)/resolve_btfids

BINARY_IN  := $(BINARY)-in.o



all: $(BINARY)



$(OUTPUT) $(OUTPUT)/libbpf $(OUTPUT)/libsubcmd:

$(OUTPUT) $(OUTPUT)/libsubcmd $(LIBBPF_OUT):

	$(call msg,MKDIR,,$@)

	$(Q)mkdir -p $(@)



$(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 $(LIBBPF_SRC)  OUTPUT=$(LIBBPF_OUT) $(abspath $@)

$(BPFOBJ): $(wildcard $(LIBBPF_SRC)/*.[ch] $(LIBBPF_SRC)/Makefile) | $(LIBBPF_OUT)

	$(Q)$(MAKE) $(submake_extras) -C $(LIBBPF_SRC) OUTPUT=$(LIBBPF_OUT)    \

		    DESTDIR=$(LIBBPF_DESTDIR) prefix=			       \

		    $(abspath $@) install_headers



CFLAGS := -g \

          -I$(srctree)/tools/include \

          -I$(srctree)/tools/include/uapi \

          -I$(LIBBPF_SRC) \

          -I$(LIBBPF_INCLUDE) \

          -I$(SUBCMD_SRC)



LIBS = -lelf -lz
@@ -65,7 +70,8 @@ $(BINARY): $(BPFOBJ) $(SUBCMDOBJ) $(BINARY_IN) 
clean_objects := $(wildcard $(OUTPUT)/*.o                \

                            $(OUTPUT)/.*.o.cmd           \

                            $(OUTPUT)/.*.o.d             \

                            $(OUTPUT)/libbpf             \

                            $(LIBBPF_OUT)                \

                            $(LIBBPF_DESTDIR)            \

                            $(OUTPUT)/libsubcmd          \

                            $(OUTPUT)/resolve_btfids)

tools/bpf/resolve_btfids/main.c

+2 −2
Original line number Diff line number Diff line
@@ -60,8 +60,8 @@ 
#include <linux/rbtree.h>

#include <linux/zalloc.h>

#include <linux/err.h>

#include <btf.h>

#include <libbpf.h>

#include <bpf/btf.h>

#include <bpf/libbpf.h>

#include <parse-options.h>



#define BTF_IDS_SECTION	".BTF_ids"

tools/testing/selftests/bpf/Makefile

+5 −2
Original line number Diff line number Diff line
@@ -122,9 +122,11 @@ BPFOBJ := $(BUILD_DIR)/libbpf/libbpf.a 
ifneq ($(CROSS_COMPILE),)

HOST_BUILD_DIR		:= $(BUILD_DIR)/host

HOST_SCRATCH_DIR	:= $(OUTPUT)/host-tools

HOST_INCLUDE_DIR	:= $(HOST_SCRATCH_DIR)/include

else

HOST_BUILD_DIR		:= $(BUILD_DIR)

HOST_SCRATCH_DIR	:= $(SCRATCH_DIR)

HOST_INCLUDE_DIR	:= $(INCLUDE_DIR)

endif

HOST_BPFOBJ := $(HOST_BUILD_DIR)/libbpf/libbpf.a

RESOLVE_BTFIDS := $(HOST_BUILD_DIR)/resolve_btfids/resolve_btfids
@@ -227,7 +229,7 @@ docs-clean: 


$(BPFOBJ): $(wildcard $(BPFDIR)/*.[ch] $(BPFDIR)/Makefile)		       \

	   ../../../include/uapi/linux/bpf.h                                   \

	   | $(INCLUDE_DIR) $(BUILD_DIR)/libbpf

	   | $(BUILD_DIR)/libbpf

	$(Q)$(MAKE) $(submake_extras) -C $(BPFDIR) OUTPUT=$(BUILD_DIR)/libbpf/ \

		    EXTRA_CFLAGS='-g -O0'				       \

		    DESTDIR=$(SCRATCH_DIR) prefix= all install_headers
@@ -235,7 +237,7 @@ $(BPFOBJ): $(wildcard $(BPFDIR)/*.[ch] $(BPFDIR)/Makefile) \ 
ifneq ($(BPFOBJ),$(HOST_BPFOBJ))

$(HOST_BPFOBJ): $(wildcard $(BPFDIR)/*.[ch] $(BPFDIR)/Makefile)                \

	   ../../../include/uapi/linux/bpf.h                                   \

	   | $(INCLUDE_DIR) $(HOST_BUILD_DIR)/libbpf

	   | $(HOST_BUILD_DIR)/libbpf

	$(Q)$(MAKE) $(submake_extras) -C $(BPFDIR)                             \

		    EXTRA_CFLAGS='-g -O0'				       \

		    OUTPUT=$(HOST_BUILD_DIR)/libbpf/ CC=$(HOSTCC) LD=$(HOSTLD) \
@@ -260,6 +262,7 @@ $(RESOLVE_BTFIDS): $(HOST_BPFOBJ) | $(HOST_BUILD_DIR)/resolve_btfids \ 
		       $(TOOLSDIR)/lib/str_error_r.c

	$(Q)$(MAKE) $(submake_extras) -C $(TOOLSDIR)/bpf/resolve_btfids	\

		CC=$(HOSTCC) LD=$(HOSTLD) AR=$(HOSTAR) \

		LIBBPF_INCLUDE=$(HOST_INCLUDE_DIR) \

		OUTPUT=$(HOST_BUILD_DIR)/resolve_btfids/ BPFOBJ=$(HOST_BPFOBJ)



# Get Clang's default includes on this system, as opposed to those seen by