From: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Date: Thu, 26 Mar 2009 14:24:22 +0000 (+0100)
Subject: [S390] kernel: Disable switch_amode by default
X-Git-Tag: v2.6.30-rc1~659^2~40
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=4b2a8b6043979f1e6cc8aaa4116c95b31ae942ec;p=platform%2Fkernel%2Flinux-stable.git

[S390] kernel: Disable switch_amode by default

Disable switch_amode by default because pagetable walk on pre z9
hardware has negative performance impact.

Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
---

diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
index 0b8ad7b..dd3c517 100644
--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -301,11 +301,7 @@ static int __init early_parse_mem(char *p)
 early_param("mem", early_parse_mem);
 
 #ifdef CONFIG_S390_SWITCH_AMODE
-#ifdef CONFIG_PGSTE
-unsigned int switch_amode = 1;
-#else
 unsigned int switch_amode = 0;
-#endif
 EXPORT_SYMBOL_GPL(switch_amode);
 
 static int set_amode_and_uaccess(unsigned long user_amode,