From 4b2a8b6043979f1e6cc8aaa4116c95b31ae942ec Mon Sep 17 00:00:00 2001
From: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Date: Thu, 26 Mar 2009 15:24:22 +0100
Subject: [PATCH] [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>
---
arch/s390/kernel/setup.c | 4 ----
1 file changed, 4 deletions(-)
diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
index 0b8ad7b4f8f36..dd3c517362706 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,
--
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