1# SPDX-License-Identifier: GPL-2.0 2# 3# Kbuild for top-level directory of the kernel 4# This file takes care of the following: 5# 1) Generate bounds.h 6# 2) Generate timeconst.h 7# 3) Generate asm-offsets.h (may need bounds.h and timeconst.h) 8# 4) Check for missing system calls 9# 5) Generate constants.py (may need bounds.h) 10 11##### 12# 1) Generate bounds.h 13 14bounds-file := include/generated/bounds.h 15 16always := $(bounds-file) 17targets := kernel/bounds.s 18 19# We use internal kbuild rules to avoid the "is up to date" message from make 20kernel/bounds.s: kernel/bounds.c FORCE 21 $(call if_changed_dep,cc_s_c) 22 23$(obj)/$(bounds-file): kernel/bounds.s FORCE 24 $(call filechk,offsets,__LINUX_BOUNDS_H__) 25 26##### 27# 2) Generate timeconst.h 28 29timeconst-file := include/generated/timeconst.h 30 31targets += $(timeconst-file) 32 33quiet_cmd_gentimeconst = GEN $@ 34define cmd_gentimeconst 35 (echo $(CONFIG_HZ) | bc -q $< ) > $@ 36endef 37define filechk_gentimeconst 38 (echo $(CONFIG_HZ) | bc -q $< ) 39endef 40 41$(obj)/$(timeconst-file): kernel/time/timeconst.bc FORCE 42 $(call filechk,gentimeconst) 43 44##### 45# 3) Generate asm-offsets.h 46# 47 48offsets-file := include/generated/asm-offsets.h 49 50always += $(offsets-file) 51targets += arch/$(SRCARCH)/kernel/asm-offsets.s 52 53# We use internal kbuild rules to avoid the "is up to date" message from make 54arch/$(SRCARCH)/kernel/asm-offsets.s: arch/$(SRCARCH)/kernel/asm-offsets.c \ 55 $(obj)/$(timeconst-file) $(obj)/$(bounds-file) FORCE 56 $(call if_changed_dep,cc_s_c) 57 58$(obj)/$(offsets-file): arch/$(SRCARCH)/kernel/asm-offsets.s FORCE 59 $(call filechk,offsets,__ASM_OFFSETS_H__) 60 61##### 62# 4) Check for missing system calls 63# 64 65always += missing-syscalls 66targets += missing-syscalls 67 68quiet_cmd_syscalls = CALL $< 69 cmd_syscalls = $(CONFIG_SHELL) $< $(CC) $(c_flags) $(missing_syscalls_flags) 70 71missing-syscalls: scripts/checksyscalls.sh $(offsets-file) FORCE 72 $(call cmd,syscalls) 73 74##### 75# 5) Generate constants for Python GDB integration 76# 77 78extra-$(CONFIG_GDB_SCRIPTS) += build_constants_py 79 80build_constants_py: $(obj)/$(timeconst-file) $(obj)/$(bounds-file) 81 @$(MAKE) $(build)=scripts/gdb/linux $@ 82 83# Keep these three files during make clean 84no-clean-files := $(bounds-file) $(offsets-file) $(timeconst-file) 85