1# SPDX-License-Identifier: GPL-2.0 2# Rules to generate bpf objs 3CLANG ?= clang 4SCRATCH_DIR := $(OUTPUT)/tools 5BUILD_DIR := $(SCRATCH_DIR)/build 6BPFDIR := $(top_srcdir)/tools/lib/bpf 7APIDIR := $(top_srcdir)/tools/include/uapi 8 9CCINCLUDE += -I$(selfdir)/bpf 10CCINCLUDE += -I$(top_srcdir)/usr/include/ 11CCINCLUDE += -I$(SCRATCH_DIR)/include 12 13BPFOBJ := $(BUILD_DIR)/libbpf/libbpf.a 14 15MAKE_DIRS := $(BUILD_DIR)/libbpf 16$(MAKE_DIRS): 17 $(call msg,MKDIR,,$@) 18 $(Q)mkdir -p $@ 19 20# Get Clang's default includes on this system, as opposed to those seen by 21# '--target=bpf'. This fixes "missing" files on some architectures/distros, 22# such as asm/byteorder.h, asm/socket.h, asm/sockios.h, sys/cdefs.h etc. 23# 24# Use '-idirafter': Don't interfere with include mechanics except where the 25# build would have failed anyways. 26define get_sys_includes 27$(shell $(1) $(2) -v -E - </dev/null 2>&1 \ 28 | sed -n '/<...> search starts here:/,/End of search list./{ s| \(/.*\)|-idirafter \1|p }') \ 29$(shell $(1) $(2) -dM -E - </dev/null | grep '__riscv_xlen ' | awk '{printf("-D__riscv_xlen=%d -D__BITS_PER_LONG=%d", $$3, $$3)}') 30endef 31 32ifneq ($(CROSS_COMPILE),) 33CLANG_TARGET_ARCH = --target=$(notdir $(CROSS_COMPILE:%-=%)) 34endif 35 36CLANG_SYS_INCLUDES = $(call get_sys_includes,$(CLANG),$(CLANG_TARGET_ARCH)) 37 38BPF_PROG_OBJS := $(patsubst %.c,$(OUTPUT)/%.o,$(wildcard *.bpf.c)) 39 40$(BPF_PROG_OBJS): $(OUTPUT)/%.o : %.c $(BPFOBJ) | $(MAKE_DIRS) 41 $(call msg,BPF_PROG,,$@) 42 $(Q)$(CLANG) -O2 -g --target=bpf $(CCINCLUDE) $(CLANG_SYS_INCLUDES) \ 43 -c $< -o $@ 44 45$(BPFOBJ): $(wildcard $(BPFDIR)/*.[ch] $(BPFDIR)/Makefile) \ 46 $(APIDIR)/linux/bpf.h \ 47 | $(BUILD_DIR)/libbpf 48 $(call msg,MAKE,,$@) 49 $(Q)$(MAKE) $(submake_extras) -C $(BPFDIR) OUTPUT=$(BUILD_DIR)/libbpf/ \ 50 EXTRA_CFLAGS='-g -O0' \ 51 DESTDIR=$(SCRATCH_DIR) prefix= all install_headers 52 53EXTRA_CLEAN += $(SCRATCH_DIR) 54