2 # Kbuild for top-level directory of the kernel
3 # This file takes care of the following:
5 # 2) Generate timeconst.h
6 # 3) Generate asm-offsets.h (may need bounds.h and timeconst.h)
7 # 4) Check for missing system calls
8 # 5) Generate constants.py (may need bounds.h)
10 # Default sed regexp - multiline due to syntax constraints
12 "/^->/{s:->#\(.*\):/* \1 */:; \
13 s:^->\([^ ]*\) [\$$#]*\([-0-9]*\) \(.*\):#define \1 \2 /* \3 */:; \
14 s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; \
18 # Use filechk to avoid rebuilds when a header changes, but the resulting file
20 define filechk_offsets
25 echo " * DO NOT MODIFY."; \
27 echo " * This file was generated by Kbuild"; \
36 # 1) Generate bounds.h
38 bounds-file := include/generated/bounds.h
40 always := $(bounds-file)
41 targets := kernel/bounds.s
43 # We use internal kbuild rules to avoid the "is up to date" message from make
44 kernel/bounds.s: kernel/bounds.c FORCE
45 $(Q)mkdir -p $(dir $@)
46 $(call if_changed_dep,cc_s_c)
48 $(obj)/$(bounds-file): kernel/bounds.s FORCE
49 $(call filechk,offsets,__LINUX_BOUNDS_H__)
52 # 2) Generate timeconst.h
54 timeconst-file := include/generated/timeconst.h
56 targets += $(timeconst-file)
58 quiet_cmd_gentimeconst = GEN $@
59 define cmd_gentimeconst
60 (echo $(CONFIG_HZ) | bc -q $< ) > $@
62 define filechk_gentimeconst
63 (echo $(CONFIG_HZ) | bc -q $< )
66 $(obj)/$(timeconst-file): kernel/time/timeconst.bc FORCE
67 $(call filechk,gentimeconst)
70 # 3) Generate asm-offsets.h
73 offsets-file := include/generated/asm-offsets.h
75 always += $(offsets-file)
76 targets += arch/$(SRCARCH)/kernel/asm-offsets.s
78 # We use internal kbuild rules to avoid the "is up to date" message from make
79 arch/$(SRCARCH)/kernel/asm-offsets.s: arch/$(SRCARCH)/kernel/asm-offsets.c \
80 $(obj)/$(timeconst-file) $(obj)/$(bounds-file) FORCE
81 $(Q)mkdir -p $(dir $@)
82 $(call if_changed_dep,cc_s_c)
84 $(obj)/$(offsets-file): arch/$(SRCARCH)/kernel/asm-offsets.s FORCE
85 $(call filechk,offsets,__ASM_OFFSETS_H__)
88 # 4) Check for missing system calls
91 always += missing-syscalls
92 targets += missing-syscalls
94 quiet_cmd_syscalls = CALL $<
95 cmd_syscalls = $(CONFIG_SHELL) $< $(CC) $(c_flags) $(missing_syscalls_flags)
97 missing-syscalls: scripts/checksyscalls.sh $(offsets-file) FORCE
101 # 5) Generate constants for Python GDB integration
104 extra-$(CONFIG_GDB_SCRIPTS) += build_constants_py
106 build_constants_py: $(obj)/$(timeconst-file) $(obj)/$(bounds-file)
107 @$(MAKE) $(build)=scripts/gdb/linux $@
109 # Keep these three files during make clean
110 no-clean-files := $(bounds-file) $(offsets-file) $(timeconst-file)