1 # SPDX-License-Identifier: GPL-2.0
3 # Kbuild for top-level directory of the kernel
4 # This file takes care of the following:
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)
12 # 1) Generate bounds.h
14 bounds-file := include/generated/bounds.h
16 always := $(bounds-file)
17 targets := kernel/bounds.s
19 $(bounds-file): kernel/bounds.s FORCE
20 $(call filechk,offsets,__LINUX_BOUNDS_H__)
23 # 2) Generate timeconst.h
25 timeconst-file := include/generated/timeconst.h
27 targets += $(timeconst-file)
29 quiet_cmd_gentimeconst = GEN $@
30 define cmd_gentimeconst
31 (echo $(CONFIG_HZ) | bc -q $< ) > $@
33 define filechk_gentimeconst
34 (echo $(CONFIG_HZ) | bc -q $< )
37 $(timeconst-file): kernel/time/timeconst.bc FORCE
38 $(call filechk,gentimeconst)
41 # 3) Generate asm-offsets.h
44 offsets-file := include/generated/asm-offsets.h
46 always += $(offsets-file)
47 targets += arch/$(SRCARCH)/kernel/asm-offsets.s
49 arch/$(SRCARCH)/kernel/asm-offsets.s: $(timeconst-file) $(bounds-file)
51 $(offsets-file): arch/$(SRCARCH)/kernel/asm-offsets.s FORCE
52 $(call filechk,offsets,__ASM_OFFSETS_H__)
55 # 4) Check for missing system calls
58 always += missing-syscalls
59 targets += missing-syscalls
61 quiet_cmd_syscalls = CALL $<
62 cmd_syscalls = $(CONFIG_SHELL) $< $(CC) $(c_flags) $(missing_syscalls_flags)
64 missing-syscalls: scripts/checksyscalls.sh $(offsets-file) FORCE
68 # 5) Generate constants for Python GDB integration
71 extra-$(CONFIG_GDB_SCRIPTS) += build_constants_py
73 build_constants_py: $(timeconst-file) $(bounds-file)
74 @$(MAKE) $(build)=scripts/gdb/linux $@
76 # Keep these three files during make clean
77 no-clean-files := $(bounds-file) $(offsets-file) $(timeconst-file)