1# SPDX-License-Identifier: GPL-2.0 2 3HID_SAMPLES_PATH ?= $(abspath $(srctree)/$(src)) 4TOOLS_PATH := $(HID_SAMPLES_PATH)/../../tools 5 6pound := \# 7 8# List of programs to build 9tprogs-y += hid_mouse 10tprogs-y += hid_surface_dial 11 12# Libbpf dependencies 13LIBBPF_SRC = $(TOOLS_PATH)/lib/bpf 14LIBBPF_OUTPUT = $(abspath $(HID_SAMPLES_PATH))/libbpf 15LIBBPF_DESTDIR = $(LIBBPF_OUTPUT) 16LIBBPF_INCLUDE = $(LIBBPF_DESTDIR)/include 17LIBBPF = $(LIBBPF_OUTPUT)/libbpf.a 18 19EXTRA_HEADERS := hid_bpf_attach.h 20EXTRA_BPF_HEADERS := hid_bpf_helpers.h 21 22hid_mouse-objs := hid_mouse.o 23hid_surface_dial-objs := hid_surface_dial.o 24 25# Tell kbuild to always build the programs 26always-y := $(tprogs-y) 27 28ifeq ($(ARCH), arm) 29# Strip all except -D__LINUX_ARM_ARCH__ option needed to handle linux 30# headers when arm instruction set identification is requested. 31ARM_ARCH_SELECTOR := $(filter -D__LINUX_ARM_ARCH__%, $(KBUILD_CFLAGS)) 32BPF_EXTRA_CFLAGS := $(ARM_ARCH_SELECTOR) 33TPROGS_CFLAGS += $(ARM_ARCH_SELECTOR) 34endif 35 36ifeq ($(ARCH), mips) 37TPROGS_CFLAGS += -D__SANE_USERSPACE_TYPES__ 38ifdef CONFIG_MACH_LOONGSON64 39BPF_EXTRA_CFLAGS += -I$(srctree)/arch/mips/include/asm/mach-loongson64 40BPF_EXTRA_CFLAGS += -I$(srctree)/arch/mips/include/asm/mach-generic 41endif 42endif 43 44TPROGS_CFLAGS += -Wall -O2 45TPROGS_CFLAGS += -Wmissing-prototypes 46TPROGS_CFLAGS += -Wstrict-prototypes 47 48TPROGS_CFLAGS += -I$(objtree)/usr/include 49TPROGS_CFLAGS += -I$(LIBBPF_INCLUDE) 50TPROGS_CFLAGS += -I$(srctree)/tools/include 51 52ifdef SYSROOT 53TPROGS_CFLAGS += --sysroot=$(SYSROOT) 54TPROGS_LDFLAGS := -L$(SYSROOT)/usr/lib 55endif 56 57TPROGS_LDLIBS += $(LIBBPF) -lelf -lz 58 59# Allows pointing LLC/CLANG to a LLVM backend with bpf support, redefine on cmdline: 60# make M=samples/bpf LLC=~/git/llvm-project/llvm/build/bin/llc CLANG=~/git/llvm-project/llvm/build/bin/clang 61LLC ?= llc 62CLANG ?= clang 63OPT ?= opt 64LLVM_DIS ?= llvm-dis 65LLVM_OBJCOPY ?= llvm-objcopy 66LLVM_READELF ?= llvm-readelf 67BTF_PAHOLE ?= pahole 68 69# Detect that we're cross compiling and use the cross compiler 70ifdef CROSS_COMPILE 71CLANG_ARCH_ARGS = --target=$(notdir $(CROSS_COMPILE:%-=%)) 72endif 73 74# Don't evaluate probes and warnings if we need to run make recursively 75ifneq ($(src),) 76HDR_PROBE := $(shell printf "$(pound)include <linux/types.h>\n struct list_head { int a; }; int main() { return 0; }" | \ 77 $(CC) $(TPROGS_CFLAGS) $(TPROGS_LDFLAGS) -x c - \ 78 -o /dev/null 2>/dev/null && echo okay) 79 80ifeq ($(HDR_PROBE),) 81$(warning WARNING: Detected possible issues with include path.) 82$(warning WARNING: Please install kernel headers locally (make headers_install).) 83endif 84 85BTF_LLC_PROBE := $(shell $(LLC) -march=bpf -mattr=help 2>&1 | grep dwarfris) 86BTF_PAHOLE_PROBE := $(shell $(BTF_PAHOLE) --help 2>&1 | grep BTF) 87BTF_OBJCOPY_PROBE := $(shell $(LLVM_OBJCOPY) --help 2>&1 | grep -i 'usage.*llvm') 88BTF_LLVM_PROBE := $(shell echo "int main() { return 0; }" | \ 89 $(CLANG) -target bpf -O2 -g -c -x c - -o ./llvm_btf_verify.o; \ 90 $(LLVM_READELF) -S ./llvm_btf_verify.o | grep BTF; \ 91 /bin/rm -f ./llvm_btf_verify.o) 92 93BPF_EXTRA_CFLAGS += -fno-stack-protector 94ifneq ($(BTF_LLVM_PROBE),) 95 BPF_EXTRA_CFLAGS += -g 96else 97ifneq ($(and $(BTF_LLC_PROBE),$(BTF_PAHOLE_PROBE),$(BTF_OBJCOPY_PROBE)),) 98 BPF_EXTRA_CFLAGS += -g 99 LLC_FLAGS += -mattr=dwarfris 100 DWARF2BTF = y 101endif 102endif 103endif 104 105# Trick to allow make to be run from this directory 106all: 107 $(MAKE) -C ../../ M=$(CURDIR) HID_SAMPLES_PATH=$(CURDIR) 108 109clean: 110 $(MAKE) -C ../../ M=$(CURDIR) clean 111 @find $(CURDIR) -type f -name '*~' -delete 112 @$(RM) -r $(CURDIR)/libbpf $(CURDIR)/bpftool 113 114$(LIBBPF): $(wildcard $(LIBBPF_SRC)/*.[ch] $(LIBBPF_SRC)/Makefile) | $(LIBBPF_OUTPUT) 115# Fix up variables inherited from Kbuild that tools/ build system won't like 116 $(MAKE) -C $(LIBBPF_SRC) RM='rm -rf' EXTRA_CFLAGS="$(TPROGS_CFLAGS)" \ 117 LDFLAGS=$(TPROGS_LDFLAGS) srctree=$(HID_SAMPLES_PATH)/../../ \ 118 O= OUTPUT=$(LIBBPF_OUTPUT)/ DESTDIR=$(LIBBPF_DESTDIR) prefix= \ 119 $@ install_headers 120 121BPFTOOLDIR := $(TOOLS_PATH)/bpf/bpftool 122BPFTOOL_OUTPUT := $(abspath $(HID_SAMPLES_PATH))/bpftool 123BPFTOOL := $(BPFTOOL_OUTPUT)/bootstrap/bpftool 124$(BPFTOOL): $(wildcard $(BPFTOOLDIR)/*.[ch] $(BPFTOOLDIR)/Makefile) | $(BPFTOOL_OUTPUT) 125 $(MAKE) -C $(BPFTOOLDIR) srctree=$(HID_SAMPLES_PATH)/../../ \ 126 OUTPUT=$(BPFTOOL_OUTPUT)/ bootstrap 127 128$(LIBBPF_OUTPUT) $(BPFTOOL_OUTPUT): 129 $(call msg,MKDIR,$@) 130 $(Q)mkdir -p $@ 131 132FORCE: 133 134 135# Verify LLVM compiler tools are available and bpf target is supported by llc 136.PHONY: verify_cmds verify_target_bpf $(CLANG) $(LLC) 137 138verify_cmds: $(CLANG) $(LLC) 139 @for TOOL in $^ ; do \ 140 if ! (which -- "$${TOOL}" > /dev/null 2>&1); then \ 141 echo "*** ERROR: Cannot find LLVM tool $${TOOL}" ;\ 142 exit 1; \ 143 else true; fi; \ 144 done 145 146verify_target_bpf: verify_cmds 147 @if ! (${LLC} -march=bpf -mattr=help > /dev/null 2>&1); then \ 148 echo "*** ERROR: LLVM (${LLC}) does not support 'bpf' target" ;\ 149 echo " NOTICE: LLVM version >= 3.7.1 required" ;\ 150 exit 2; \ 151 else true; fi 152 153$(HID_SAMPLES_PATH)/*.c: verify_target_bpf $(LIBBPF) 154$(src)/*.c: verify_target_bpf $(LIBBPF) 155 156libbpf_hdrs: $(LIBBPF) 157 158.PHONY: libbpf_hdrs 159 160$(obj)/hid_mouse.o: $(obj)/hid_mouse.skel.h 161$(obj)/hid_surface_dial.o: $(obj)/hid_surface_dial.skel.h 162 163-include $(HID_SAMPLES_PATH)/Makefile.target 164 165VMLINUX_BTF_PATHS ?= $(abspath $(if $(O),$(O)/vmlinux)) \ 166 $(abspath $(if $(KBUILD_OUTPUT),$(KBUILD_OUTPUT)/vmlinux)) \ 167 $(abspath ./vmlinux) 168VMLINUX_BTF ?= $(abspath $(firstword $(wildcard $(VMLINUX_BTF_PATHS)))) 169 170$(obj)/vmlinux.h: $(VMLINUX_BTF) $(BPFTOOL) 171ifeq ($(VMLINUX_H),) 172ifeq ($(VMLINUX_BTF),) 173 $(error Cannot find a vmlinux for VMLINUX_BTF at any of "$(VMLINUX_BTF_PATHS)",\ 174 build the kernel or set VMLINUX_BTF or VMLINUX_H variable) 175endif 176 $(Q)$(BPFTOOL) btf dump file $(VMLINUX_BTF) format c > $@ 177else 178 $(Q)cp "$(VMLINUX_H)" $@ 179endif 180 181clean-files += vmlinux.h 182 183# Get Clang's default includes on this system, as opposed to those seen by 184# '-target bpf'. This fixes "missing" files on some architectures/distros, 185# such as asm/byteorder.h, asm/socket.h, asm/sockios.h, sys/cdefs.h etc. 186# 187# Use '-idirafter': Don't interfere with include mechanics except where the 188# build would have failed anyways. 189define get_sys_includes 190$(shell $(1) -v -E - </dev/null 2>&1 \ 191 | sed -n '/<...> search starts here:/,/End of search list./{ s| \(/.*\)|-idirafter \1|p }') \ 192$(shell $(1) -dM -E - </dev/null | grep '#define __riscv_xlen ' | sed 's/#define /-D/' | sed 's/ /=/') 193endef 194 195CLANG_SYS_INCLUDES = $(call get_sys_includes,$(CLANG)) 196 197EXTRA_BPF_HEADERS_SRC := $(addprefix $(src)/,$(EXTRA_BPF_HEADERS)) 198 199$(obj)/%.bpf.o: $(src)/%.bpf.c $(EXTRA_BPF_HEADERS_SRC) $(obj)/vmlinux.h 200 @echo " CLANG-BPF " $@ 201 $(Q)$(CLANG) -g -O2 -target bpf -D__TARGET_ARCH_$(SRCARCH) \ 202 -Wno-compare-distinct-pointer-types -I$(srctree)/include \ 203 -I$(srctree)/samples/bpf -I$(srctree)/tools/include \ 204 -I$(LIBBPF_INCLUDE) $(CLANG_SYS_INCLUDES) \ 205 -c $(filter %.bpf.c,$^) -o $@ 206 207LINKED_SKELS := hid_mouse.skel.h hid_surface_dial.skel.h 208clean-files += $(LINKED_SKELS) 209 210hid_mouse.skel.h-deps := hid_mouse.bpf.o hid_bpf_attach.bpf.o 211hid_surface_dial.skel.h-deps := hid_surface_dial.bpf.o hid_bpf_attach.bpf.o 212 213LINKED_BPF_SRCS := $(patsubst %.bpf.o,%.bpf.c,$(foreach skel,$(LINKED_SKELS),$($(skel)-deps))) 214 215BPF_SRCS_LINKED := $(notdir $(wildcard $(src)/*.bpf.c)) 216BPF_OBJS_LINKED := $(patsubst %.bpf.c,$(obj)/%.bpf.o, $(BPF_SRCS_LINKED)) 217BPF_SKELS_LINKED := $(addprefix $(obj)/,$(LINKED_SKELS)) 218 219$(BPF_SKELS_LINKED): $(BPF_OBJS_LINKED) $(BPFTOOL) 220 @echo " BPF GEN-OBJ " $(@:.skel.h=) 221 $(Q)$(BPFTOOL) gen object $(@:.skel.h=.lbpf.o) $(addprefix $(obj)/,$($(@F)-deps)) 222 @echo " BPF GEN-SKEL" $(@:.skel.h=) 223 $(Q)$(BPFTOOL) gen skeleton $(@:.skel.h=.lbpf.o) name $(notdir $(@:.skel.h=)) > $@ 224 225# asm/sysreg.h - inline assembly used by it is incompatible with llvm. 226# But, there is no easy way to fix it, so just exclude it since it is 227# useless for BPF samples. 228# below we use long chain of commands, clang | opt | llvm-dis | llc, 229# to generate final object file. 'clang' compiles the source into IR 230# with native target, e.g., x64, arm64, etc. 'opt' does bpf CORE IR builtin 231# processing (llvm12) and IR optimizations. 'llvm-dis' converts 232# 'opt' output to IR, and finally 'llc' generates bpf byte code. 233$(obj)/%.o: $(src)/%.c 234 @echo " CLANG-bpf " $@ 235 $(Q)$(CLANG) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) $(BPF_EXTRA_CFLAGS) \ 236 -I$(obj) -I$(srctree)/tools/testing/selftests/bpf/ \ 237 -I$(LIBBPF_INCLUDE) \ 238 -D__KERNEL__ -D__BPF_TRACING__ -Wno-unused-value -Wno-pointer-sign \ 239 -D__TARGET_ARCH_$(SRCARCH) -Wno-compare-distinct-pointer-types \ 240 -Wno-gnu-variable-sized-type-not-at-end \ 241 -Wno-address-of-packed-member -Wno-tautological-compare \ 242 -Wno-unknown-warning-option $(CLANG_ARCH_ARGS) \ 243 -fno-asynchronous-unwind-tables \ 244 -I$(srctree)/samples/hid/ \ 245 -O2 -emit-llvm -Xclang -disable-llvm-passes -c $< -o - | \ 246 $(OPT) -O2 -mtriple=bpf-pc-linux | $(LLVM_DIS) | \ 247 $(LLC) -march=bpf $(LLC_FLAGS) -filetype=obj -o $@ 248ifeq ($(DWARF2BTF),y) 249 $(BTF_PAHOLE) -J $@ 250endif 251