Doc/sysctl/kernel.txt: document threads-max

[linux-2.6-block.git] / Kbuild

diff --git a/Kbuild b/Kbuild
index b8b708ad6dc3815eb0d23bfea2c972d03b9477c0..6f0d82a9245d897c89a63819e857f474ab93066e 100644 (file)
--- a/Kbuild
+++ b/Kbuild
@@ -5,39 +5,46 @@
 # 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
+# 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_bounds = GEN     $@
-define cmd_bounds
+# Use filechk to avoid rebuilds when a header changes, but the resulting file
+# does not
+define filechk_offsets
        (set -e; \
-        echo "#ifndef __LINUX_BOUNDS_H__"; \
-        echo "#define __LINUX_BOUNDS_H__"; \
+        echo "#ifndef $2"; \
+        echo "#define $2"; \
         echo "/*"; \
         echo " * DO NOT MODIFY."; \
         echo " *"; \
         echo " * This file was generated by Kbuild"; \
-        echo " *"; \
         echo " */"; \
         echo ""; \
-        sed -ne $(sed-y) $<; \
+        sed -ne $(sed-y); \
         echo ""; \
-        echo "#endif" ) > $@
+        echo "#endif" )
 endef
 
+#####
+# 1) Generate bounds.h
+
+bounds-file := include/generated/bounds.h
+
+always  := $(bounds-file)
+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 $@)
-       $(call cmd,bounds)
+$(obj)/$(bounds-file): kernel/bounds.s FORCE
+       $(call filechk,offsets,__LINUX_BOUNDS_H__)
 
 #####
 # 2) Generate asm-offsets.h
@@ -46,43 +53,16 @@ $(obj)/$(bounds-file): kernel/bounds.s Kbuild
 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
-       $(call cmd,offsets)
+$(obj)/$(offsets-file): arch/$(SRCARCH)/kernel/asm-offsets.s FORCE
+       $(call filechk,offsets,__ASM_OFFSETS_H__)
 
 #####
 # 3) Check for missing system calls