[PATCH] x86: Don't use MWAIT on AMD Family 10
It doesn't put the CPU into deeper sleep states, so it's better to use the standard
idle loop to save power. But allow to reenable it anyways for benchmarking.
I also removed the obsolete idle=halt on i386
Cc: andreas.herrmann@amd.com
Signed-off-by: Andi Kleen <ak@suse.de>
diff --git a/arch/x86_64/kernel/process.c b/arch/x86_64/kernel/process.c
index d8d5ccc..4f21765 100644
--- a/arch/x86_64/kernel/process.c
+++ b/arch/x86_64/kernel/process.c
@@ -288,16 +288,18 @@
static int __init idle_setup (char *str)
{
- if (!strncmp(str, "poll", 4)) {
+ if (!strcmp(str, "poll")) {
printk("using polling idle threads.\n");
pm_idle = poll_idle;
- }
+ } else if (!strcmp(str, "mwait"))
+ force_mwait = 1;
+ else
+ return -1;
boot_option_idle_override = 1;
- return 1;
+ return 0;
}
-
-__setup("idle=", idle_setup);
+early_param("idle", idle_setup);
/* Prints also some state that isn't saved in the pt_regs */
void __show_regs(struct pt_regs * regs)