xref: /linux/Kbuild (revision bd628c1bed7902ec1f24ba0fe70758949146abbe)
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  := $(bounds-file)
17targets := kernel/bounds.s
18
19$(bounds-file): kernel/bounds.s FORCE
20	$(call filechk,offsets,__LINUX_BOUNDS_H__)
21
22#####
23# 2) Generate timeconst.h
24
25timeconst-file := include/generated/timeconst.h
26
27targets += $(timeconst-file)
28
29filechk_gentimeconst = echo $(CONFIG_HZ) | bc -q $<
30
31$(timeconst-file): kernel/time/timeconst.bc FORCE
32	$(call filechk,gentimeconst)
33
34#####
35# 3) Generate asm-offsets.h
36#
37
38offsets-file := include/generated/asm-offsets.h
39
40always  += $(offsets-file)
41targets += arch/$(SRCARCH)/kernel/asm-offsets.s
42
43arch/$(SRCARCH)/kernel/asm-offsets.s: $(timeconst-file) $(bounds-file)
44
45$(offsets-file): arch/$(SRCARCH)/kernel/asm-offsets.s FORCE
46	$(call filechk,offsets,__ASM_OFFSETS_H__)
47
48#####
49# 4) Check for missing system calls
50#
51
52always += missing-syscalls
53targets += missing-syscalls
54
55quiet_cmd_syscalls = CALL    $<
56      cmd_syscalls = $(CONFIG_SHELL) $< $(CC) $(c_flags) $(missing_syscalls_flags)
57
58missing-syscalls: scripts/checksyscalls.sh $(offsets-file) FORCE
59	$(call cmd,syscalls)
60
61#####
62# 5) Generate constants for Python GDB integration
63#
64
65extra-$(CONFIG_GDB_SCRIPTS) += build_constants_py
66
67build_constants_py: $(timeconst-file) $(bounds-file)
68	@$(MAKE) $(build)=scripts/gdb/linux $@
69
70# Keep these three files during make clean
71no-clean-files := $(bounds-file) $(offsets-file) $(timeconst-file)
72