1# SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
2include ../../scripts/Makefile.include
3
4OUTPUT ?= $(abspath .output)/
5
6BPFTOOL_OUTPUT := $(OUTPUT)bpftool/
7DEFAULT_BPFTOOL := $(BPFTOOL_OUTPUT)bootstrap/bpftool
8BPFTOOL ?= $(DEFAULT_BPFTOOL)
9BPF_TARGET_ENDIAN ?= --target=bpf
10LIBBPF_SRC := $(abspath ../../lib/bpf)
11BPFOBJ_OUTPUT := $(OUTPUT)libbpf/
12BPFOBJ := $(BPFOBJ_OUTPUT)libbpf.a
13BPF_DESTDIR := $(BPFOBJ_OUTPUT)
14BPF_INCLUDE := $(BPF_DESTDIR)/include
15INCLUDES := -I$(OUTPUT) -I$(BPF_INCLUDE) -I$(abspath ../../include/uapi)
16CFLAGS := -g -Wall $(CLANG_CROSS_FLAGS)
17CFLAGS += $(EXTRA_CFLAGS)
18LDFLAGS += $(EXTRA_LDFLAGS)
19LDLIBS += -lelf -lz
20
21# Try to detect best kernel BTF source
22KERNEL_REL := $(shell uname -r)
23VMLINUX_BTF_PATHS := $(if $(O),$(O)/vmlinux)		\
24	$(if $(KBUILD_OUTPUT),$(KBUILD_OUTPUT)/vmlinux) \
25	../../../vmlinux /sys/kernel/btf/vmlinux	\
26	/boot/vmlinux-$(KERNEL_REL)
27VMLINUX_BTF_PATH := $(or $(VMLINUX_BTF),$(firstword			       \
28					  $(wildcard $(VMLINUX_BTF_PATHS))))
29
30ifneq ($(V),1)
31MAKEFLAGS += --no-print-directory
32submake_extras := feature_display=0
33endif
34
35.DELETE_ON_ERROR:
36
37.PHONY: all clean runqslower libbpf_hdrs
38all: runqslower
39
40runqslower: $(OUTPUT)/runqslower
41
42clean:
43	$(call QUIET_CLEAN, runqslower)
44	$(Q)$(RM) -r $(BPFOBJ_OUTPUT) $(BPFTOOL_OUTPUT)
45	$(Q)$(RM) $(OUTPUT)*.o $(OUTPUT)*.d
46	$(Q)$(RM) $(OUTPUT)*.skel.h $(OUTPUT)vmlinux.h
47	$(Q)$(RM) $(OUTPUT)runqslower
48	$(Q)$(RM) -r .output
49
50libbpf_hdrs: $(BPFOBJ)
51
52$(OUTPUT)/runqslower: $(OUTPUT)/runqslower.o $(BPFOBJ)
53	$(QUIET_LINK)$(CC) $(CFLAGS) $(LDFLAGS) $^ $(LDLIBS) -o $@
54
55$(OUTPUT)/runqslower.o: runqslower.h $(OUTPUT)/runqslower.skel.h	      \
56			$(OUTPUT)/runqslower.bpf.o | libbpf_hdrs
57
58$(OUTPUT)/runqslower.bpf.o: $(OUTPUT)/vmlinux.h runqslower.h | libbpf_hdrs
59
60$(OUTPUT)/%.skel.h: $(OUTPUT)/%.bpf.o | $(BPFTOOL)
61	$(QUIET_GEN)$(BPFTOOL) gen skeleton $< > $@
62
63$(OUTPUT)/%.bpf.o: %.bpf.c $(BPFOBJ) | $(OUTPUT)
64	$(QUIET_GEN)$(CLANG) -g -O2 $(BPF_TARGET_ENDIAN) $(INCLUDES)	      \
65		 -c $(filter %.c,$^) -o $@ &&				      \
66	$(LLVM_STRIP) -g $@
67
68$(OUTPUT)/%.o: %.c | $(OUTPUT)
69	$(QUIET_CC)$(CC) $(CFLAGS) $(INCLUDES) -c $(filter %.c,$^) -o $@
70
71$(OUTPUT) $(BPFOBJ_OUTPUT) $(BPFTOOL_OUTPUT):
72	$(QUIET_MKDIR)mkdir -p $@
73
74$(OUTPUT)/vmlinux.h: $(VMLINUX_BTF_PATH) | $(OUTPUT) $(BPFTOOL)
75ifeq ($(VMLINUX_H),)
76	$(Q)if [ ! -e "$(VMLINUX_BTF_PATH)" ] ; then \
77		echo "Couldn't find kernel BTF; set VMLINUX_BTF to"	       \
78			"specify its location." >&2;			       \
79		exit 1;\
80	fi
81	$(QUIET_GEN)$(BPFTOOL) btf dump file $(VMLINUX_BTF_PATH) format c > $@
82else
83	$(Q)cp "$(VMLINUX_H)" $@
84endif
85
86$(BPFOBJ): $(wildcard $(LIBBPF_SRC)/*.[ch] $(LIBBPF_SRC)/Makefile) | $(BPFOBJ_OUTPUT)
87	$(Q)$(MAKE) $(submake_extras) -C $(LIBBPF_SRC) OUTPUT=$(BPFOBJ_OUTPUT) \
88		    DESTDIR=$(BPFOBJ_OUTPUT) prefix= $(abspath $@) install_headers
89
90$(DEFAULT_BPFTOOL): | $(BPFTOOL_OUTPUT)
91	$(Q)$(MAKE) $(submake_extras) -C ../bpftool OUTPUT=$(BPFTOOL_OUTPUT) bootstrap
92