Kbuild

   1 #
   2 # Kbuild for top-level directory of the kernel
   3 # This file takes care of the following:
   4 # 1) Generate asm-offsets.h
   5
   6 #####
   7 # 1) Generate asm-offsets.h
   8 #
   9
  10 offsets-file := include/asm-$(ARCH)/asm-offsets.h
  11
  12 always  := $(offsets-file)
  13 targets := $(offsets-file)
  14 targets += arch/$(ARCH)/kernel/asm-offsets.s
  15
  16 # Default sed regexp - multiline due to syntax constraints
  17 define sed-y
  18         "/^->/{s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; s:->::; p;}"
  19 endef
  20 # Override default regexp for specific architectures
  21 sed-$(CONFIG_MIPS) := "/^@@@/{s/^@@@//; s/ \#.*\$$//; p;}"
  22
  23 quiet_cmd_offsets = GEN     $@
  24 define cmd_offsets
  25         (set -e; \
  26          echo "#ifndef __ASM_OFFSETS_H__"; \
  27          echo "#define __ASM_OFFSETS_H__"; \
  28          echo "/*"; \
  29          echo " * DO NOT MODIFY."; \
  30          echo " *"; \
  31          echo " * This file was generated by $(srctree)/Kbuild"; \
  32          echo " *"; \
  33          echo " */"; \
  34          echo ""; \
  35          sed -ne $(sed-y) $<; \
  36          echo ""; \
  37          echo "#endif" ) > $@
  38 endef
  39
  40 # We use internal kbuild rules to avoid the "is up to date" message from make
  41 arch/$(ARCH)/kernel/asm-offsets.s: arch/$(ARCH)/kernel/asm-offsets.c FORCE
  42         $(Q)mkdir -p $(dir $@)
  43         $(call if_changed_dep,cc_s_c)
  44
  45 $(obj)/$(offsets-file): arch/$(ARCH)/kernel/asm-offsets.s Kbuild
  46         $(Q)mkdir -p $(dir $@)
  47         $(call cmd,offsets)
  48