diff --git a/study/debug/tools/bcc/00-code/simple/Makefile.bak b/study/debug/tools/bcc/00-code/simple/Makefile.bak
deleted file mode 100644
index 327572a..0000000
--- a/study/debug/tools/bcc/00-code/simple/Makefile.bak
+++ /dev/null
@@ -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 $@