LXR linux/Kbuild

   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# 5) Generate constants.py (may need bounds.h)
   9
  10#####
  11# 1) Generate bounds.h
  12
  13bounds-file := include/generated/bounds.h
  14
  15always  := $(bounds-file)
  16targets := kernel/bounds.s
  17
  18# We use internal kbuild rules to avoid the "is up to date" message from make
  19kernel/bounds.s: kernel/bounds.c FORCE
  20        $(Q)mkdir -p $(dir $@)
  21        $(call if_changed_dep,cc_s_c)
  22
  23$(obj)/$(bounds-file): kernel/bounds.s FORCE
  24        $(call filechk,offsets,__LINUX_BOUNDS_H__)
  25
  26#####
  27# 2) Generate timeconst.h
  28
  29timeconst-file := include/generated/timeconst.h
  30
  31targets += $(timeconst-file)
  32
  33quiet_cmd_gentimeconst = GEN     $@
  34define cmd_gentimeconst
  35        (echo $(CONFIG_HZ) | bc -q $< ) > $@
  36endef
  37define filechk_gentimeconst
  38        (echo $(CONFIG_HZ) | bc -q $< )
  39endef
  40
  41$(obj)/$(timeconst-file): kernel/time/timeconst.bc FORCE
  42        $(call filechk,gentimeconst)
  43
  44#####
  45# 3) Generate asm-offsets.h
  46#
  47
  48offsets-file := include/generated/asm-offsets.h
  49
  50always  += $(offsets-file)
  51targets += arch/$(SRCARCH)/kernel/asm-offsets.s
  52
  53# We use internal kbuild rules to avoid the "is up to date" message from make
  54arch/$(SRCARCH)/kernel/asm-offsets.s: arch/$(SRCARCH)/kernel/asm-offsets.c \
  55                                      $(obj)/$(timeconst-file) $(obj)/$(bounds-file) FORCE
  56        $(Q)mkdir -p $(dir $@)
  57        $(call if_changed_dep,cc_s_c)
  58
  59$(obj)/$(offsets-file): arch/$(SRCARCH)/kernel/asm-offsets.s FORCE
  60        $(call filechk,offsets,__ASM_OFFSETS_H__)
  61
  62#####
  63# 4) Check for missing system calls
  64#
  65
  66always += missing-syscalls
  67targets += missing-syscalls
  68
  69quiet_cmd_syscalls = CALL    $<
  70      cmd_syscalls = $(CONFIG_SHELL) $< $(CC) $(c_flags) $(missing_syscalls_flags)
  71
  72missing-syscalls: scripts/checksyscalls.sh $(offsets-file) FORCE
  73        $(call cmd,syscalls)
  74
  75#####
  76# 5) Generate constants for Python GDB integration
  77#
  78
  79extra-$(CONFIG_GDB_SCRIPTS) += build_constants_py
  80
  81build_constants_py: $(obj)/$(timeconst-file) $(obj)/$(bounds-file)
  82        @$(MAKE) $(build)=scripts/gdb/linux $@
  83
  84# Keep these three files during make clean
  85no-clean-files := $(bounds-file) $(offsets-file) $(timeconst-file)
  86