[S390] kernel: Disable switch_amode by default
authorGerald Schaefer <gerald.schaefer@de.ibm.com>
Thu, 26 Mar 2009 14:24:22 +0000 (15:24 +0100)
committerMartin Schwidefsky <schwidefsky@de.ibm.com>
Thu, 26 Mar 2009 14:24:18 +0000 (15:24 +0100)
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

index 0b8ad7b4f8f36ae713329cb408f8420b0da7d168..dd3c5173627065761e17374db9310292b62eb188 100644 (file)
@@ -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,