samples/hid/Makefile

   1 # SPDX-License-Identifier: GPL-2.0
   2
   3 HID_SAMPLES_PATH ?= $(abspath $(srctree)/$(src))
   4 TOOLS_PATH := $(HID_SAMPLES_PATH)/../../tools
   5
   6 pound := \#
   7
   8 # List of programs to build
   9 tprogs-y += hid_mouse
  10 tprogs-y += hid_surface_dial
  11
  12 # Libbpf dependencies
  13 LIBBPF_SRC = $(TOOLS_PATH)/lib/bpf
  14 LIBBPF_OUTPUT = $(abspath $(HID_SAMPLES_PATH))/libbpf
  15 LIBBPF_DESTDIR = $(LIBBPF_OUTPUT)
  16 LIBBPF_INCLUDE = $(LIBBPF_DESTDIR)/include
  17 LIBBPF = $(LIBBPF_OUTPUT)/libbpf.a
  18
  19 EXTRA_HEADERS := hid_bpf_attach.h
  20 EXTRA_BPF_HEADERS := hid_bpf_helpers.h
  21
  22 hid_mouse-objs := hid_mouse.o
  23 hid_surface_dial-objs := hid_surface_dial.o
  24
  25 # Tell kbuild to always build the programs
  26 always-y := $(tprogs-y)
  27
  28 ifeq ($(ARCH), arm)
  29 # Strip all except -D__LINUX_ARM_ARCH__ option needed to handle linux
  30 # headers when arm instruction set identification is requested.
  31 ARM_ARCH_SELECTOR := $(filter -D__LINUX_ARM_ARCH__%, $(KBUILD_CFLAGS))
  32 BPF_EXTRA_CFLAGS := $(ARM_ARCH_SELECTOR)
  33 TPROGS_CFLAGS += $(ARM_ARCH_SELECTOR)
  34 endif
  35
  36 ifeq ($(ARCH), mips)
  37 TPROGS_CFLAGS += -D__SANE_USERSPACE_TYPES__
  38 ifdef CONFIG_MACH_LOONGSON64
  39 BPF_EXTRA_CFLAGS += -I$(srctree)/arch/mips/include/asm/mach-loongson64
  40 BPF_EXTRA_CFLAGS += -I$(srctree)/arch/mips/include/asm/mach-generic
  41 endif
  42 endif
  43
  44 TPROGS_CFLAGS += -Wall -O2
  45 TPROGS_CFLAGS += -Wmissing-prototypes
  46 TPROGS_CFLAGS += -Wstrict-prototypes
  47
  48 TPROGS_CFLAGS += -I$(objtree)/usr/include
  49 TPROGS_CFLAGS += -I$(LIBBPF_INCLUDE)
  50 TPROGS_CFLAGS += -I$(srctree)/tools/include
  51
  52 ifdef SYSROOT
  53 TPROGS_CFLAGS += --sysroot=$(SYSROOT)
  54 TPROGS_LDFLAGS := -L$(SYSROOT)/usr/lib
  55 endif
  56
  57 TPROGS_LDLIBS                   += $(LIBBPF) -lelf -lz
  58
  59 # Allows pointing LLC/CLANG to a LLVM backend with bpf support, redefine on cmdline:
  60 # make M=samples/bpf LLC=~/git/llvm-project/llvm/build/bin/llc CLANG=~/git/llvm-project/llvm/build/bin/clang
  61 LLC ?= llc
  62 CLANG ?= clang
  63 OPT ?= opt
  64 LLVM_DIS ?= llvm-dis
  65 LLVM_OBJCOPY ?= llvm-objcopy
  66 LLVM_READELF ?= llvm-readelf
  67 BTF_PAHOLE ?= pahole
  68
  69 # Detect that we're cross compiling and use the cross compiler
  70 ifdef CROSS_COMPILE
  71 CLANG_ARCH_ARGS = --target=$(notdir $(CROSS_COMPILE:%-=%))
  72 endif
  73
  74 # Don't evaluate probes and warnings if we need to run make recursively
  75 ifneq ($(src),)
  76 HDR_PROBE := $(shell printf "$(pound)include <linux/types.h>\n struct list_head { int a; }; int main() { return 0; }" | \
  77         $(CC) $(TPROGS_CFLAGS) $(TPROGS_LDFLAGS) -x c - \
  78         -o /dev/null 2>/dev/null && echo okay)
  79
  80 ifeq ($(HDR_PROBE),)
  81 $(warning WARNING: Detected possible issues with include path.)
  82 $(warning WARNING: Please install kernel headers locally (make headers_install).)
  83 endif
  84
  85 BTF_LLC_PROBE := $(shell $(LLC) -march=bpf -mattr=help 2>&1 | grep dwarfris)
  86 BTF_PAHOLE_PROBE := $(shell $(BTF_PAHOLE) --help 2>&1 | grep BTF)
  87 BTF_OBJCOPY_PROBE := $(shell $(LLVM_OBJCOPY) --help 2>&1 | grep -i 'usage.*llvm')
  88 BTF_LLVM_PROBE := $(shell echo "int main() { return 0; }" | \
  89                           $(CLANG) --target=bpf -O2 -g -c -x c - -o ./llvm_btf_verify.o; \
  90                           $(LLVM_READELF) -S ./llvm_btf_verify.o | grep BTF; \
  91                           /bin/rm -f ./llvm_btf_verify.o)
  92
  93 BPF_EXTRA_CFLAGS += -fno-stack-protector
  94 ifneq ($(BTF_LLVM_PROBE),)
  95         BPF_EXTRA_CFLAGS += -g
  96 else
  97 ifneq ($(and $(BTF_LLC_PROBE),$(BTF_PAHOLE_PROBE),$(BTF_OBJCOPY_PROBE)),)
  98         BPF_EXTRA_CFLAGS += -g
  99         LLC_FLAGS += -mattr=dwarfris
 100         DWARF2BTF = y
 101 endif
 102 endif
 103 endif
 104
 105 # Trick to allow make to be run from this directory
 106 all:
 107         $(MAKE) -C ../../ M=$(CURDIR) HID_SAMPLES_PATH=$(CURDIR)
 108
 109 clean:
 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
 121 BPFTOOLDIR := $(TOOLS_PATH)/bpf/bpftool
 122 BPFTOOL_OUTPUT := $(abspath $(HID_SAMPLES_PATH))/bpftool
 123 BPFTOOL := $(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
 132 FORCE:
 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
 138 verify_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
 146 verify_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
 156 libbpf_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
 165 VMLINUX_BTF_PATHS ?= $(abspath $(if $(O),$(O)/vmlinux))                         \
 166                      $(abspath $(if $(KBUILD_OUTPUT),$(KBUILD_OUTPUT)/vmlinux)) \
 167                      $(abspath ./vmlinux)
 168 VMLINUX_BTF ?= $(abspath $(firstword $(wildcard $(VMLINUX_BTF_PATHS))))
 169
 170 $(obj)/vmlinux.h: $(VMLINUX_BTF) $(BPFTOOL)
 171 ifeq ($(VMLINUX_H),)
 172 ifeq ($(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)
 175 endif
 176         $(Q)$(BPFTOOL) btf dump file $(VMLINUX_BTF) format c > $@
 177 else
 178         $(Q)cp "$(VMLINUX_H)" $@
 179 endif
 180
 181 clean-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.
 189 define 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/ /=/')
 193 endef
 194
 195 CLANG_SYS_INCLUDES = $(call get_sys_includes,$(CLANG))
 196
 197 EXTRA_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
 207 LINKED_SKELS := hid_mouse.skel.h hid_surface_dial.skel.h
 208 clean-files += $(LINKED_SKELS)
 209
 210 hid_mouse.skel.h-deps := hid_mouse.bpf.o hid_bpf_attach.bpf.o
 211 hid_surface_dial.skel.h-deps := hid_surface_dial.bpf.o hid_bpf_attach.bpf.o
 212
 213 LINKED_BPF_SRCS := $(patsubst %.bpf.o,%.bpf.c,$(foreach skel,$(LINKED_SKELS),$($(skel)-deps)))
 214
 215 BPF_SRCS_LINKED := $(notdir $(wildcard $(src)/*.bpf.c))
 216 BPF_OBJS_LINKED := $(patsubst %.bpf.c,$(obj)/%.bpf.o, $(BPF_SRCS_LINKED))
 217 BPF_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 $@
 248 ifeq ($(DWARF2BTF),y)
 249         $(BTF_PAHOLE) -J $@
 250 endif