1# 2# Kbuild for top-level directory of the kernel 3# This file takes care of the following: 4# 1) Generate bounds.h 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 9# Default sed regexp - multiline due to syntax constraints 10define sed-y 11 "/^->/{s:->#\(.*\):/* \1 */:; \ 12 s:^->\([^ ]*\) [\$$#]*\([-0-9]*\) \(.*\):#define \1 \2 /* \3 */:; \ 13 s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; \ 14 s:->::; p;}" 15endef 16 17# Use filechk to avoid rebuilds when a header changes, but the resulting file 18# does not 19define filechk_offsets 20 (set -e; \ 21 echo "#ifndef $2"; \ 22 echo "#define $2"; \ 23 echo "/*"; \ 24 echo " * DO NOT MODIFY."; \ 25 echo " *"; \ 26 echo " * This file was generated by Kbuild"; \ 27 echo " */"; \ 28 echo ""; \ 29 sed -ne $(sed-y); \ 30 echo ""; \ 31 echo "#endif" ) 32endef 33 34##### 35# 1) Generate bounds.h 36 37bounds-file := include/generated/bounds.h 38 39always := $(bounds-file) 40targets := kernel/bounds.s 41 42# We use internal kbuild rules to avoid the "is up to date" message from make 43kernel/bounds.s: kernel/bounds.c FORCE 44 $(Q)mkdir -p $(dir $@) 45 $(call if_changed_dep,cc_s_c) 46 47$(obj)/$(bounds-file): kernel/bounds.s FORCE 48 $(call filechk,offsets,__LINUX_BOUNDS_H__) 49 50##### 51# 2) Generate timeconst.h 52 53timeconst-file := include/generated/timeconst.h 54 55targets += $(timeconst-file) 56 57quiet_cmd_gentimeconst = GEN $@ 58define cmd_gentimeconst 59 (echo $(CONFIG_HZ) | bc -q $< ) > $@ 60endef 61define filechk_gentimeconst 62 (echo $(CONFIG_HZ) | bc -q $< ) 63endef 64 65$(obj)/$(timeconst-file): kernel/time/timeconst.bc FORCE 66 $(call filechk,gentimeconst) 67 68##### 69# 3) Generate asm-offsets.h 70# 71 72offsets-file := include/generated/asm-offsets.h 73 74always += $(offsets-file) 75targets += arch/$(SRCARCH)/kernel/asm-offsets.s 76 77# We use internal kbuild rules to avoid the "is up to date" message from make 78arch/$(SRCARCH)/kernel/asm-offsets.s: arch/$(SRCARCH)/kernel/asm-offsets.c \ 79 $(obj)/$(timeconst-file) $(obj)/$(bounds-file) FORCE 80 $(Q)mkdir -p $(dir $@) 81 $(call if_changed_dep,cc_s_c) 82 83$(obj)/$(offsets-file): arch/$(SRCARCH)/kernel/asm-offsets.s FORCE 84 $(call filechk,offsets,__ASM_OFFSETS_H__) 85 86##### 87# 4) Check for missing system calls 88# 89 90always += missing-syscalls 91targets += missing-syscalls 92 93quiet_cmd_syscalls = CALL $< 94 cmd_syscalls = $(CONFIG_SHELL) $< $(CC) $(c_flags) $(missing_syscalls_flags) 95 96missing-syscalls: scripts/checksyscalls.sh $(offsets-file) FORCE 97 $(call cmd,syscalls) 98 99# Keep these three files during make clean 100no-clean-files := $(bounds-file) $(offsets-file) $(timeconst-file) 101