x86: simplify idle selection

default_idle is selected in cpu_idle(), when no other idle routine is
selected. Select it in select_idle_routine() when mwait is not
selected.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 7 insertions, 11 deletions

diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index ba370dc8685b..b3078f4ce25b 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -139,27 +139,23 @@ static int __cpuinit mwait_usable(const struct cpuinfo_x86 *c)
 
 void __cpuinit select_idle_routine(const struct cpuinfo_x86 *c)
 {
-        static int selected;
-
-        if (selected)
-                return;
 #ifdef CONFIG_X86_SMP
         if (pm_idle == poll_idle && smp_num_siblings > 1) {
                 printk(KERN_WARNING "WARNING: polling idle and HT enabled,"
                         " performance may degrade.\n");
         }
 #endif
+        if (pm_idle)
+                return;
+
         if (cpu_has(c, X86_FEATURE_MWAIT) && mwait_usable(c)) {
                 /*
-                 * Skip, if setup has overridden idle.
                  * One CPU supports mwait => All CPUs supports mwait
                  */
-                if (!pm_idle) {
-                        printk(KERN_INFO "using mwait in idle threads.\n");
-                        pm_idle = mwait_idle;
-                }
-        }
-        selected = 1;
+                printk(KERN_INFO "using mwait in idle threads.\n");
+                pm_idle = mwait_idle;
+        } else
+                pm_idle = default_idle;
 }
 
 static int __init idle_setup(char *str)