simple eBPF example...

This commit is contained in:
gatieme
2017-11-12 14:47:25 +08:00
parent 928ecf8c49
commit aedbf881c9

View File

@@ -1,99 +0,0 @@
# SPDX-License-Identifier: GPL-2.0
srctree := ~/Work/Kernel/linux/linux
objtree := ~/Work/Kernel/linux/build/x86_64
# kbuild trick to avoid linker error. Can be omitted if a module is built.
obj- := dummy.o
# List of programs to build
hostprogs-y += memcpy_kprobe
hostprogs-y += memcpy_stat
# Libbpf dependencies
LIBBPF := ./bpf/bpf.o
LIBBPF_LOAD := ./bpf_load.o
memcpy_kprobe-objs := $(LIBBPF) $(LIBBPF_LOAD) memcpy_kprobe_user.o
memcpy_stat-objs := $(LIBBPF) $(LIBBPF_LOAD) memcpy_stat_user.o
# Tell kbuild to always build the programs
always := $(hostprogs-y)
always += memcpy_stat_kern.o
always += memcpy_kprobe_kern.o
HOSTCFLAGS += -I$(objtree)/usr/include
HOSTCFLAGS += -I$(srctree)/include
HOSTCFLAGS += -I$(srctree)/include/uapi
HOSTCFLAGS += -I$(srctree)/tools/lib/
HOSTCFLAGS += -I$(srctree)/tools/testing/selftests/bpf/
HOSTCFLAGS += -I$(srctree)/tools/lib/
HOSTCFLAGS += -I$(srctree)/tools/include
HOSTCFLAGS += -I$(srctree)/tools/include/uapi
HOSTCFLAGS += -I$(srctree)/tools/perf
HOSTCFLAGS_bpf_load.o += -I$(objtree)/usr/include -Wno-unused-variable
HOSTLOADLIBES_memcpy_kprobe += -lelf
HOSTLOADLIBES_syscall_tp += -lelf
# Allows pointing LLC/CLANG to a LLVM backend with bpf support, redefine on cmdline:
# make samples/bpf/ LLC=~/git/llvm/build/bin/llc CLANG=~/git/llvm/build/bin/clang
LLC ?= llc
CLANG ?= clang
# Trick to allow make to be run from this directory
all:
$(MAKE) -C $(objtree) M=$(CURDIR)
clean:
$(MAKE) -C $(objtree) M=$(CURDIR) clean
@rm -f *~
$(obj)/syscall_nrs.s: $(src)/syscall_nrs.c
$(call if_changed_dep,cc_s_c)
$(obj)/syscall_nrs.h: $(obj)/syscall_nrs.s FORCE
$(call filechk,offsets,__SYSCALL_NRS_H__)
clean-files += syscall_nrs.h
FORCE:
# Verify LLVM compiler tools are available and bpf target is supported by llc
.PHONY: verify_cmds verify_target_bpf $(CLANG) $(LLC)
verify_cmds: $(CLANG) $(LLC)
@for TOOL in $^ ; do \
if ! (which -- "$${TOOL}" > /dev/null 2>&1); then \
echo "*** ERROR: Cannot find LLVM tool $${TOOL}" ;\
exit 1; \
else true; fi; \
done
verify_target_bpf: verify_cmds
@if ! (${LLC} -march=bpf -mattr=help > /dev/null 2>&1); then \
echo "*** ERROR: LLVM (${LLC}) does not support 'bpf' target" ;\
echo " NOTICE: LLVM version >= 3.7.1 required" ;\
exit 2; \
else true; fi
$(src)/*.c: verify_target_bpf
$(obj)/tracex5_kern.o: $(obj)/syscall_nrs.h
# asm/sysreg.h - inline assembly used by it is incompatible with llvm.
# But, there is no easy way to fix it, so just exclude it since it is
# useless for BPF samples.
$(obj)/%.o: $(src)/%.c
$(CLANG) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) $(EXTRA_CFLAGS) -I$(obj) \
-I$(srctree)/tools/testing/selftests/bpf/ \
-D__KERNEL__ -D__ASM_SYSREG_H -Wno-unused-value -Wno-pointer-sign \
-Wno-compare-distinct-pointer-types \
-Wno-gnu-variable-sized-type-not-at-end \
-Wno-address-of-packed-member -Wno-tautological-compare \
-Wno-unknown-warning-option \
-O2 -emit-llvm -c $< -o -| $(LLC) -march=bpf -filetype=obj -o $@