# 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
+# 2) Generate timeconst.h
+# 3) Generate asm-offsets.h (may need bounds.h and timeconst.h)
+# 4) Check for missing system calls
# Default sed regexp - multiline due to syntax constraints
define sed-y
s:->::; p;}"
endef
-quiet_cmd_offsets = GEN $@
-define cmd_offsets
+# Use filechk to avoid rebuilds when a header changes, but the resulting file
+# does not
+define filechk_offsets
(set -e; \
echo "#ifndef $2"; \
echo "#define $2"; \
echo " * This file was generated by Kbuild"; \
echo " */"; \
echo ""; \
- sed -ne $(sed-y) $<; \
+ sed -ne $(sed-y); \
echo ""; \
- echo "#endif" ) > $@
+ echo "#endif" )
endef
#####
bounds-file := include/generated/bounds.h
always := $(bounds-file)
-targets := $(bounds-file) kernel/bounds.s
+targets := kernel/bounds.s
# 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 $@)
- $(call cmd,offsets,__LINUX_BOUNDS_H__)
+$(obj)/$(bounds-file): kernel/bounds.s FORCE
+ $(call filechk,offsets,__LINUX_BOUNDS_H__)
+
+#####
+# 2) Generate timeconst.h
+
+timeconst-file := include/generated/timeconst.h
+
+#always += $(timeconst-file)
+targets += $(timeconst-file)
+
+quiet_cmd_gentimeconst = GEN $@
+define cmd_gentimeconst
+ (echo $(CONFIG_HZ) | bc -q $< ) > $@
+endef
+define filechk_gentimeconst
+ (echo $(CONFIG_HZ) | bc -q $< )
+endef
+
+$(obj)/$(timeconst-file): kernel/time/timeconst.bc FORCE
+ $(call filechk,gentimeconst)
#####
-# 2) Generate asm-offsets.h
+# 3) Generate asm-offsets.h
#
offsets-file := include/generated/asm-offsets.h
always += $(offsets-file)
-targets += $(offsets-file)
targets += arch/$(SRCARCH)/kernel/asm-offsets.s
# 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
+ $(obj)/$(timeconst-file) $(obj)/$(bounds-file) FORCE
$(Q)mkdir -p $(dir $@)
$(call if_changed_dep,cc_s_c)
-$(obj)/$(offsets-file): arch/$(SRCARCH)/kernel/asm-offsets.s Kbuild
- $(call cmd,offsets,__ASM_OFFSETS_H__)
+$(obj)/$(offsets-file): arch/$(SRCARCH)/kernel/asm-offsets.s FORCE
+ $(call filechk,offsets,__ASM_OFFSETS_H__)
#####
-# 3) Check for missing system calls
+# 4) Check for missing system calls
#
always += missing-syscalls
missing-syscalls: scripts/checksyscalls.sh $(offsets-file) FORCE
$(call cmd,syscalls)
-# Keep these two files during make clean
-no-clean-files := $(bounds-file) $(offsets-file)
+# Keep these three files during make clean
+no-clean-files := $(bounds-file) $(offsets-file) $(timeconst-file)