linux-yocto/Kbuild
Linus Torvalds c9e2a72ff1 Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6
* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6:
  initramfs: Fix build break on symbol-prefixed archs
  initramfs: fix initramfs size calculation
  initramfs: generalize initramfs_data.xxx.S variants
  scripts/kallsyms: Enable error messages while hush up unnecessary warnings
  scripts/setlocalversion: update comment
  kbuild: Use a single clean rule for kernel and external modules
  kbuild: Do not run make clean in $(srctree)
  scripts/mod/modpost.c: fix commentary accordingly to last changes
  kbuild: Really don't clean bounds.h and asm-offsets.h
2010-10-28 15:13:55 -07:00

2.4 KiB

Kbuild for top-level directory of the kernel

This file takes care of the following:

1) Generate bounds.h

2) Generate asm-offsets.h (may need bounds.h)

3) Check for missing system calls

1) Generate bounds.h

bounds-file := include/generated/bounds.h

always := $(bounds-file) targets := $(bounds-file) kernel/bounds.s

quiet_cmd_bounds = GEN $@ define cmd_bounds (set -e;
echo "#ifndef LINUX_BOUNDS_H";
echo "#define LINUX_BOUNDS_H";
echo "/*";
echo " * DO NOT MODIFY.";
echo " *";
echo " * This file was generated by Kbuild";
echo " *";
echo " */";
echo "";
sed -ne $(sed-y) $<;
echo "";
echo "#endif" ) > $@ endef

We use internal kbuild rules to avoid the "is up to date" message from make

kernel/bounds.s: kernel/bounds.c FORCE $(Q)mkdir -p $(dir $@) $(call if_changed_dep,cc_s_c)

$(obj)/$(bounds-file): kernel/bounds.s Kbuild $(Q)mkdir -p $(dir $@) $(call cmd,bounds)

2) Generate asm-offsets.h

offsets-file := include/generated/asm-offsets.h

always += $(offsets-file) targets += $(offsets-file) targets += arch/$(SRCARCH)/kernel/asm-offsets.s

Default sed regexp - multiline due to syntax constraints

define sed-y "/^->/{s:->#.*:/* \1 /:;
s:^->[^ ]* [$$#]
[-0-9]* .*:#define \1 \2 /* \3 /:;
s:^->[^ ]* [$$#]
[^ ]* .*:#define \1 \2 /* \3 */:;
s:->::; p;}" endef

quiet_cmd_offsets = GEN $@ define cmd_offsets (set -e;
echo "#ifndef ASM_OFFSETS_H";
echo "#define ASM_OFFSETS_H";
echo "/*";
echo " * DO NOT MODIFY.";
echo " *";
echo " * This file was generated by Kbuild";
echo " *";
echo " */";
echo "";
sed -ne $(sed-y) $<;
echo "";
echo "#endif" ) > $@ endef

We use internal kbuild rules to avoid the "is up to date" message from make

arch/$(SRCARCH)/kernel/asm-offsets.s: arch/$(SRCARCH)/kernel/asm-offsets.c
$(obj)/$(bounds-file) FORCE $(Q)mkdir -p $(dir $@) $(call if_changed_dep,cc_s_c)

$(obj)/$(offsets-file): arch/$(SRCARCH)/kernel/asm-offsets.s Kbuild $(call cmd,offsets)

3) Check for missing system calls

quiet_cmd_syscalls = CALL $< cmd_syscalls = $(CONFIG_SHELL) $< $(CC) $(c_flags)

PHONY += missing-syscalls missing-syscalls: scripts/checksyscalls.sh FORCE $(call cmd,syscalls)

Keep these two files during make clean

no-clean-files := $(bounds-file) $(offsets-file)