[PATCH] x86_64: Do not use -ffunction-sections for modules

Currently CONFIG_REORDER uses -ffunction-sections for all code;
however, creating a separate section for each function is not useful
for modules and just adds bloat.  Moving this option from CFLAGS to
CFLAGS_KERNEL shrinks module object files (e.g., the module tree for a
kernel built with most drivers as modules shrinked from 54M to 46M),
and decreases the number of sysfs files in /sys/module/*/sections/
directories.

Signed-off-by: Sergey Vlasov <vsu@altlinux.ru>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/arch/x86_64/Makefile b/arch/x86_64/Makefile
index e573e2a..431bb4b 100644 (file)
--- a/arch/x86_64/Makefile
+++ b/arch/x86_64/Makefile
@@ -27,6 +27,7 @@ LDFLAGS_vmlinux :=
 CHECKFLAGS      += -D__x86_64__ -m64
 
 cflags-y       :=
+cflags-kernel-y        :=
 cflags-$(CONFIG_MK8) += $(call cc-option,-march=k8)
 cflags-$(CONFIG_MPSC) += $(call cc-option,-march=nocona)
 cflags-$(CONFIG_GENERIC_CPU) += $(call cc-option,-mtune=generic)
@@ -35,7 +36,7 @@ cflags-y += -m64
 cflags-y += -mno-red-zone
 cflags-y += -mcmodel=kernel
 cflags-y += -pipe
-cflags-$(CONFIG_REORDER) += -ffunction-sections
+cflags-kernel-$(CONFIG_REORDER) += -ffunction-sections
 # this makes reading assembly source easier, but produces worse code
 # actually it makes the kernel smaller too.
 cflags-y += -fno-reorder-blocks
@@ -55,6 +56,7 @@ cflags-y += $(call cc-option,-funit-at-a-time)
 cflags-y += $(call cc-option,-mno-sse -mno-mmx -mno-sse2 -mno-3dnow,)
 
 CFLAGS += $(cflags-y)
+CFLAGS_KERNEL += $(cflags-kernel-y)
 AFLAGS += -m64
 
 head-y := arch/x86_64/kernel/head.o arch/x86_64/kernel/head64.o arch/x86_64/kernel/init_task.o