bpf.mk 1.8 KB

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