[tip:x86/urgent] x86: Don't generate cmpxchg8b_emu if CONFIG_X86_CMPXCHG64=y

tip-bot for Eric Dumazet
2009-10-01T06:49:37Z

Commit-ID: 04edbdef02ec4386a2ae38cab7ae7d166e17a756
Gitweb: http://git.kernel.org/tip/04edbdef02ec4386a2ae38cab7ae7d166e17a756
Author: Eric Dumazet <eric.dumazet@gmail.com>
AuthorDate: Thu, 1 Oct 2009 07:30:38 +0200
Committer: Ingo Molnar <mingo@elte.hu>
CommitDate: Thu, 1 Oct 2009 08:42:24 +0200

x86: Don't generate cmpxchg8b_emu if CONFIG_X86_CMPXCHG64=y

Conditionaly compile cmpxchg8b_emu.o and EXPORT_SYMBOL(cmpxchg8b_emu).

This reduces the kernel size a bit.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: John Stultz <johnstul@us.ibm.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
LKML-Reference: <4AC43E7E.1000600@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

---
arch/x86/kernel/i386_ksyms_32.c | 2 ++
arch/x86/lib/Makefile | 6 ++++--
2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/i386_ksyms_32.c b/arch/x86/kernel/i386_ksyms_32.c
index 1736c5a..9c3bd4a 100644
--- a/arch/x86/kernel/i386_ksyms_32.c
+++ b/arch/x86/kernel/i386_ksyms_32.c
@@ -15,8 +15,10 @@ EXPORT_SYMBOL(mcount);
* the export, but dont use it from C code, it is used
* by assembly code and is not using C calling convention!
*/
+#ifndef CONFIG_X86_CMPXCHG64
extern void cmpxchg8b_emu(void);
EXPORT_SYMBOL(cmpxchg8b_emu);
+#endif

/* Networking helper routines. */
EXPORT_SYMBOL(csum_partial_copy_generic);
diff --git a/arch/x86/lib/Makefile b/arch/x86/lib/Makefile
index 3e549b8..85f5db9 100644
--- a/arch/x86/lib/Makefile
+++ b/arch/x86/lib/Makefile
@@ -15,8 +15,10 @@ ifeq ($(CONFIG_X86_32),y)
obj-y += atomic64_32.o
lib-y += checksum_32.o
lib-y += strstr_32.o
- lib-y += semaphore_32.o string_32.o cmpxchg8b_emu.o
-
+ lib-y += semaphore_32.o string_32.o
+ifneq ($(CONFIG_X86_CMPXCHG64),y)
+ lib-y += cmpxchg8b_emu.o
+endif
lib-$(CONFIG_X86_USE_3DNOW) += mmx_32.o
else
obj-y += io_64.o iomap_copy_64.o