@@ -19,24 +19,36 @@ BPF_DIR = $(srctree)/tools/lib/bpf/
ifneq ($(OUTPUT),)
LIBBPF_OUTPUT = $(OUTPUT)/libbpf/
LIBBPF_PATH = $(LIBBPF_OUTPUT)
+ BOOTSTRAP_OUTPUT = $(OUTPUT)/bootstrap/
else
LIBBPF_PATH = $(BPF_DIR)
+ BOOTSTRAP_OUTPUT = $(CURDIR)/bootstrap/
endif
LIBBPF = $(LIBBPF_PATH)libbpf.a
+LIBBPF_BOOTSTRAP_OUTPUT = $(BOOTSTRAP_OUTPUT)libbpf/
+LIBBPF_BOOTSTRAP = $(LIBBPF_BOOTSTRAP_OUTPUT)libbpf.a
BPFTOOL_VERSION := $(shell make -rR --no-print-directory -sC ../../.. kernelversion)
-$(LIBBPF_OUTPUT):
+$(LIBBPF_OUTPUT) $(BOOTSTRAP_OUTPUT) $(LIBBPF_BOOTSTRAP_OUTPUT):
$(QUIET_MKDIR)mkdir -p $@
$(LIBBPF): FORCE | $(LIBBPF_OUTPUT)
$(Q)$(MAKE) -C $(BPF_DIR) OUTPUT=$(LIBBPF_OUTPUT) $(LIBBPF_OUTPUT)libbpf.a
+$(LIBBPF_BOOTSTRAP): FORCE | $(LIBBPF_BOOTSTRAP_OUTPUT)
+ $(Q)$(MAKE) -C $(BPF_DIR) OUTPUT=$(LIBBPF_BOOTSTRAP_OUTPUT) \
+ ARCH= CC=$(HOSTCC) LD=$(HOSTLD) $@
+
$(LIBBPF)-clean: $(LIBBPF_OUTPUT)
$(call QUIET_CLEAN, libbpf)
$(Q)$(MAKE) -C $(BPF_DIR) OUTPUT=$(LIBBPF_OUTPUT) clean >/dev/null
+$(LIBBPF_BOOTSTRAP)-clean: $(LIBBPF_BOOTSTRAP_OUTPUT)
+ $(call QUIET_CLEAN, libbpf-bootstrap)
+ $(Q)$(MAKE) -C $(BPF_DIR) OUTPUT=$(LIBBPF_BOOTSTRAP_OUTPUT) clean >/dev/null
+
prefix ?= /usr/local
bash_compdir ?= /usr/share/bash-completion/completions
@@ -94,6 +106,7 @@ CFLAGS += -DCOMPAT_NEED_REALLOCARRAY
endif
LIBS = $(LIBBPF) -lelf -lz
+LIBS_BOOTSTRAP = $(LIBBPF_BOOTSTRAP) -lelf -lz
ifeq ($(feature-libcap), 1)
CFLAGS += -DUSE_LIBCAP
LIBS += -lcap
@@ -120,9 +133,9 @@ CFLAGS += -DHAVE_LIBBFD_SUPPORT
SRCS += $(BFD_SRCS)
endif
-BPFTOOL_BOOTSTRAP := $(if $(OUTPUT),$(OUTPUT)bpftool-bootstrap,./bpftool-bootstrap)
+BPFTOOL_BOOTSTRAP := $(BOOTSTRAP_OUTPUT)bpftool
-BOOTSTRAP_OBJS = $(addprefix $(OUTPUT),main.o common.o json_writer.o gen.o btf.o)
+BOOTSTRAP_OBJS = $(addprefix $(BOOTSTRAP_OUTPUT),main.o common.o json_writer.o gen.o btf.o)
OBJS = $(patsubst %.c,$(OUTPUT)%.o,$(SRCS)) $(OUTPUT)disasm.o
VMLINUX_BTF_PATHS ?= $(if $(O),$(O)/vmlinux) \
@@ -169,20 +182,25 @@ $(OUTPUT)disasm.o: $(srctree)/kernel/bpf/disasm.c
$(OUTPUT)feature.o: | zdep
-$(BPFTOOL_BOOTSTRAP): $(BOOTSTRAP_OBJS) $(LIBBPF)
- $(QUIET_LINK)$(CC) $(CFLAGS) $(LDFLAGS) -o $@ $(BOOTSTRAP_OBJS) $(LIBS)
+$(BPFTOOL_BOOTSTRAP): $(BOOTSTRAP_OBJS) $(LIBBPF_BOOTSTRAP)
+ $(QUIET_LINK)$(HOSTCC) $(CFLAGS) $(LDFLAGS) -o $@ $(BOOTSTRAP_OBJS) \
+ $(LIBS_BOOTSTRAP)
$(OUTPUT)bpftool: $(OBJS) $(LIBBPF)
$(QUIET_LINK)$(CC) $(CFLAGS) $(LDFLAGS) -o $@ $(OBJS) $(LIBS)
+$(BOOTSTRAP_OUTPUT)%.o: %.c | $(BOOTSTRAP_OUTPUT)
+ $(QUIET_CC)$(HOSTCC) $(CFLAGS) -c -MMD -o $@ $<
+
$(OUTPUT)%.o: %.c
$(QUIET_CC)$(CC) $(CFLAGS) -c -MMD -o $@ $<
-clean: $(LIBBPF)-clean
+clean: $(LIBBPF)-clean $(LIBBPF_BOOTSTRAP)-clean
$(call QUIET_CLEAN, bpftool)
$(Q)$(RM) -- $(OUTPUT)bpftool $(OUTPUT)*.o $(OUTPUT)*.d
- $(Q)$(RM) -- $(BPFTOOL_BOOTSTRAP) $(OUTPUT)*.skel.h $(OUTPUT)vmlinux.h
+ $(Q)$(RM) -- $(OUTPUT)*.skel.h $(OUTPUT)vmlinux.h
$(Q)$(RM) -r -- $(OUTPUT)libbpf/
+ $(Q)$(RM) -r -- $(BOOTSTRAP_OUTPUT)
$(call QUIET_CLEAN, core-gen)
$(Q)$(RM) -- $(OUTPUT)FEATURE-DUMP.bpftool
$(Q)$(RM) -r -- $(OUTPUT)feature/
The bpftool build first creates an intermediate binary, executed on the host, to generate skeletons required by the final build. When cross-building bpftool for an architecture different from the host, the intermediate binary should be built using the host compiler (gcc) and the final bpftool using the cross compiler (e.g. aarch64-linux-gnu-gcc). Generate the intermediate objects into the bootstrap/ directory using the host toolchain. Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org> --- tools/bpf/bpftool/Makefile | 32 +++++++++++++++++++++++++------- 1 file changed, 25 insertions(+), 7 deletions(-)