From 46d075be585eae2b74265e4e64ca38dde16a09c6 Mon Sep 17 00:00:00 2001
From: Nick Piggin <npiggin@suse.de>
Date: Tue, 11 Nov 2008 17:50:48 +0000
Subject: powerpc: Optimise smp_wmb

Change 2d1b2027626d5151fff8ef7c06ca8e7876a1a510 ("powerpc: Fixup
lwsync at runtime") removed __SUBARCH_HAS_LWSYNC, causing smp_wmb to
revert back to eieio for all CPUs.  This restores the behaviour
intorduced in 74f0609526afddd88bef40b651da24f3167b10b2 ("powerpc:
Optimise smp_wmb on 64-bit processors").

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>
---
 arch/powerpc/include/asm/synch.h | 4 ++++
 1 file changed, 4 insertions(+)

(limited to 'arch/powerpc/include/asm/synch.h')

diff --git a/arch/powerpc/include/asm/synch.h b/arch/powerpc/include/asm/synch.h
index 45963e80f557..28f6ddbff4cf 100644
--- a/arch/powerpc/include/asm/synch.h
+++ b/arch/powerpc/include/asm/synch.h
@@ -5,6 +5,10 @@
 #include <linux/stringify.h>
 #include <asm/feature-fixups.h>
 
+#if defined(__powerpc64__) || defined(CONFIG_PPC_E500MC)
+#define __SUBARCH_HAS_LWSYNC
+#endif
+
 #ifndef __ASSEMBLY__
 extern unsigned int __start___lwsync_fixup, __stop___lwsync_fixup;
 extern void do_lwsync_fixups(unsigned long value, void *fixup_start,
-- 
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