[PATCH v2] kbuild: Consolidate header generation from ASM offset information

[Matthias Kaehlcke <mka@chromium.org>]

Largely redundant code is used in different places to generate C headers
from offset information extracted from assembly language output.
Consolidate the code in Makefile.lib and use this instead.

Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
---
Changes in v2:
- Move common stuff to Makefile.lib instead of adding a new include
- Make entire filechk_offsets macro common
- Remove wrapper from ia64 and mod Makefiles and call filechk_offsets
  directly

 Kbuild                    | 25 -------------------------
 arch/ia64/kernel/Makefile | 26 ++------------------------
 scripts/Makefile.lib      | 28 ++++++++++++++++++++++++++++
 scripts/mod/Makefile      | 28 ++--------------------------
 4 files changed, 32 insertions(+), 75 deletions(-)

diff --git a/Kbuild b/Kbuild
index 3d0ae152af7c..94c752762bc2 100644
--- a/Kbuild
+++ b/Kbuild
@@ -7,31 +7,6 @@
 # 4) Check for missing system calls
 # 5) Generate constants.py (may need bounds.h)
 
-# 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
-
-# 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 "/*"; \
-	 echo " * DO NOT MODIFY."; \
-	 echo " *"; \
-	 echo " * This file was generated by Kbuild"; \
-	 echo " */"; \
-	 echo ""; \
-	 sed -ne $(sed-y); \
-	 echo ""; \
-	 echo "#endif" )
-endef
-
 #####
 # 1) Generate bounds.h
 
diff --git a/arch/ia64/kernel/Makefile b/arch/ia64/kernel/Makefile
index 3686d6abafde..9edda5466020 100644
--- a/arch/ia64/kernel/Makefile
+++ b/arch/ia64/kernel/Makefile
@@ -50,32 +50,10 @@ CFLAGS_traps.o  += -mfixed-range=f2-f5,f16-f31
 # The gate DSO image is built using a special linker script.
 include $(src)/Makefile.gate
 
-# Calculate NR_IRQ = max(IA64_NATIVE_NR_IRQS, XEN_NR_IRQS, ...) based on config
-define sed-y
-	"/^->/{s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; s:->::; p;}"
-endef
-quiet_cmd_nr_irqs = GEN     $@
-define cmd_nr_irqs
-	(set -e; \
-	 echo "#ifndef __ASM_NR_IRQS_H__"; \
-	 echo "#define __ASM_NR_IRQS_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/nr-irqs.s: arch/$(SRCARCH)/kernel/nr-irqs.c
 	$(Q)mkdir -p $(dir $@)
 	$(call if_changed_dep,cc_s_c)
 
-include/generated/nr-irqs.h: arch/$(SRCARCH)/kernel/nr-irqs.s
-	$(Q)mkdir -p $(dir $@)
-	$(call cmd,nr_irqs)
+include/generated/nr-irqs.h: arch/$(SRCARCH)/kernel/nr-irqs.s FORCE
+	$(call filechk,offsets,__ASM_NR_IRQS_H__)
diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
index 0a07f9014944..dd567e5d59e0 100644
--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib
@@ -408,3 +408,31 @@ quiet_cmd_xzmisc = XZMISC  $@
 cmd_xzmisc = (cat $(filter-out FORCE,$^) | \
 	xz --check=crc32 --lzma2=dict=1MiB) > $@ || \
 	(rm -f $@ ; false)
+
+# ASM offsets
+# ---------------------------------------------------------------------------
+
+# Default sed regexp - multiline due to syntax constraints
+define sed-offsets
+	"/^->/{s:->#\(.*\):/* \1 */:; \
+	s:^->\([^ ]*\) [\$$#]*\([-0-9]*\) \(.*\):#define \1 \2 /* \3 */:; \
+	s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; \
+	s:->::; p;}"
+endef
+
+# 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 "/*"; \
+	 echo " * DO NOT MODIFY."; \
+	 echo " *"; \
+	 echo " * This file was generated by Kbuild"; \
+	 echo " */"; \
+	 echo ""; \
+	 sed -ne $(sed-offsets); \
+	 echo ""; \
+	 echo "#endif" )
+endef
diff --git a/scripts/mod/Makefile b/scripts/mod/Makefile
index 19d9bcadc0cc..b497d9764dcf 100644
--- a/scripts/mod/Makefile
+++ b/scripts/mod/Makefile
@@ -7,32 +7,8 @@ modpost-objs	:= modpost.o file2alias.o sumversion.o
 
 devicetable-offsets-file := devicetable-offsets.h
 
-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 __DEVICETABLE_OFFSETS_H__"; \
-	 echo "#define __DEVICETABLE_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" ) > $@
-endef
-
-$(obj)/$(devicetable-offsets-file): $(obj)/devicetable-offsets.s
-	$(call if_changed,offsets)
+$(obj)/$(devicetable-offsets-file): $(obj)/devicetable-offsets.s FORCE
+	$(call filechk,offsets,__DEVICETABLE_OFFSETS_H__)
 
 targets += $(devicetable-offsets-file) devicetable-offsets.s
 
-- 
2.12.2.715.g7642488e1d-goog