On Wed, Jul 13, 2022 at 10:48 AM Quentin Monnet <quentin@xxxxxxxxxxxxx> wrote: > > On 12/07/2022 15:58, Benjamin Tissoires wrote: [...] > > diff --git a/drivers/hid/bpf/entrypoints/Makefile b/drivers/hid/bpf/entrypoints/Makefile > > new file mode 100644 > > index 000000000000..dd60a460c6c4 > > --- /dev/null > > +++ b/drivers/hid/bpf/entrypoints/Makefile > > @@ -0,0 +1,88 @@ > > +# SPDX-License-Identifier: GPL-2.0 > > +OUTPUT := .output > > +abs_out := $(abspath $(OUTPUT)) > > + > > +CLANG ?= clang > > +LLC ?= llc > > +LLVM_STRIP ?= llvm-strip > > + > > +TOOLS_PATH := $(abspath ../../../../tools) > > +BPFTOOL_SRC := $(TOOLS_PATH)/bpf/bpftool > > +BPFTOOL_OUTPUT := $(abs_out)/bpftool > > +DEFAULT_BPFTOOL := $(OUTPUT)/sbin/bpftool > > +BPFTOOL ?= $(DEFAULT_BPFTOOL) > > + > > +LIBBPF_SRC := $(TOOLS_PATH)/lib/bpf > > +LIBBPF_OUTPUT := $(abs_out)/libbpf > > +LIBBPF_DESTDIR := $(LIBBPF_OUTPUT) > > +LIBBPF_INCLUDE := $(LIBBPF_DESTDIR)/include > > +BPFOBJ := $(LIBBPF_OUTPUT)/libbpf.a > > + > > +INCLUDES := -I$(OUTPUT) -I$(LIBBPF_INCLUDE) -I$(TOOLS_PATH)/include/uapi > > +CFLAGS := -g -Wall > > + > > +VMLINUX_BTF_PATHS ?= $(if $(O),$(O)/vmlinux) \ > > + $(if $(KBUILD_OUTPUT),$(KBUILD_OUTPUT)/vmlinux) \ > > + ../../../../vmlinux \ > > + /sys/kernel/btf/vmlinux \ > > + /boot/vmlinux-$(shell uname -r) > > +VMLINUX_BTF ?= $(abspath $(firstword $(wildcard $(VMLINUX_BTF_PATHS)))) > > +ifeq ($(VMLINUX_BTF),) > > +$(error Cannot find a vmlinux for VMLINUX_BTF at any of "$(VMLINUX_BTF_PATHS)") > > +endif > > + > > +ifeq ($(V),1) > > +Q = > > +msg = > > +else > > +Q = @ > > +msg = @printf ' %-8s %s%s\n' "$(1)" "$(notdir $(2))" "$(if $(3), $(3))"; > > +MAKEFLAGS += --no-print-directory > > +submake_extras := feature_display=0 > > +endif > > + > > +.DELETE_ON_ERROR: > > + > > +.PHONY: all clean > > + > > +all: entrypoints.lskel.h > > + > > +clean: > > + $(call msg,CLEAN) > > + $(Q)rm -rf $(OUTPUT) entrypoints > > + > > +entrypoints.lskel.h: $(OUTPUT)/entrypoints.bpf.o | $(BPFTOOL) > > + $(call msg,GEN-SKEL,$@) > > + $(Q)$(BPFTOOL) gen skeleton -L $< > $@ > > + > > + > > +$(OUTPUT)/entrypoints.bpf.o: entrypoints.bpf.c $(OUTPUT)/vmlinux.h $(BPFOBJ) | $(OUTPUT) > > + $(call msg,BPF,$@) > > + $(Q)$(CLANG) -g -O2 -target bpf $(INCLUDES) \ > > + -c $(filter %.c,$^) -o $@ && \ > > + $(LLVM_STRIP) -g $@ > > + > > +$(OUTPUT)/vmlinux.h: $(VMLINUX_BTF) $(BPFTOOL) | $(INCLUDE_DIR) > > +ifeq ($(VMLINUX_H),) > > + $(call msg,GEN,,$@) > > + $(Q)$(BPFTOOL) btf dump file $(VMLINUX_BTF) format c > $@ > > +else > > + $(call msg,CP,,$@) > > + $(Q)cp "$(VMLINUX_H)" $@ > > +endif > > + > > +$(OUTPUT) $(LIBBPF_OUTPUT) $(BPFTOOL_OUTPUT): > > + $(call msg,MKDIR,$@) > > + $(Q)mkdir -p $@ > > + > > +$(BPFOBJ): $(wildcard $(LIBBPF_SRC)/*.[ch] $(LIBBPF_SRC)/Makefile) | $(LIBBPF_OUTPUT) > > + $(Q)$(MAKE) $(submake_extras) -C $(LIBBPF_SRC) \ > > + OUTPUT=$(abspath $(dir $@))/ prefix= \ > > + DESTDIR=$(LIBBPF_DESTDIR) $(abspath $@) install_headers > > + > > +$(DEFAULT_BPFTOOL): $(BPFOBJ) | $(BPFTOOL_OUTPUT) > > + $(Q)$(MAKE) $(submake_extras) -C $(BPFTOOL_SRC) \ > > + OUTPUT=$(BPFTOOL_OUTPUT)/ \ > > + LIBBPF_OUTPUT=$(LIBBPF_OUTPUT)/ \ > > + LIBBPF_DESTDIR=$(LIBBPF_DESTDIR)/ \ > > + prefix= DESTDIR=$(abs_out)/ install-bin > > Hi Benjamin, > > Note that, at other locations where bpftool is needed to generate the > vmlinux.h or the skeletons, there is some work in progress to use only > the "bootstrap" version of bpftool (the intermediary bpftool binary used > to generate skeletons required for the final bpftool binary) [0]. This > is enough to generate these objects, it makes compiling the bpftool > binary faster, and solves some issues related to cross-compilation. It's > probably worth exploring in your case (or as a follow-up) as well. > Hi Quentin, Indeed, I applied a similar patch to [1] (the 3/3 in the series you mentioned) and I have the exact same light skeleton. I have stashed the changes locally for a future revision (I doubt everything will go through in this version ;-P ). Cheers, Benjamin > Quentin > > [0] > https://lore.kernel.org/all/20220712030813.865410-1-pulehui@xxxxxxxxxx/t/#u > [1] https://lore.kernel.org/all/20220712030813.865410-4-pulehui@xxxxxxxxxx/
