mips: Use generic idle loop

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Link: http://lkml.kernel.org/r/20130321215234.754954871@linutronix.deSigned-off-by: Thomas Gleixner <tglx@linutronix.de>

arch/mips/Kconfig

@@ -34,6 +34,7 @@ config MIPS
 	select HAVE_MEMBLOCK_NODE_MAP
 	select ARCH_DISCARD_MEMBLOCK
 	select GENERIC_SMP_IDLE_THREAD
+	select GENERIC_IDLE_LOOP
 	select BUILDTIME_EXTABLE_SORT
 	select GENERIC_CLOCKEVENTS
 	select GENERIC_CMOS_UPDATE

arch/mips/kernel/process.c

@@ -41,44 +41,26 @@
 #include <asm/inst.h>
 #include <asm/stacktrace.h>
 
-/*
- * The idle thread. There's no useful work to be done, so just try to conserve
- * power and have a low exit latency (ie sit in a loop waiting for somebody to
- * say that they'd like to reschedule)
- */
-void __noreturn cpu_idle(void)
+#ifdef CONFIG_HOTPLUG_CPU
+void arch_cpu_idle_dead(void)
 {
-	int cpu;
-
-	/* CPU is going idle. */
-	cpu = smp_processor_id();
+	/* What the heck is this check doing ? */
+	if (!cpu_isset(smp_processor_id(), cpu_callin_map))
+		play_dead();
+}
+#endif
 
-	/* endless idle loop with no priority at all */
-	while (1) {
-		tick_nohz_idle_enter();
-		rcu_idle_enter();
-		while (!need_resched() && cpu_online(cpu)) {
+void arch_cpu_idle(void)
+{
 #ifdef CONFIG_MIPS_MT_SMTC
 	extern void smtc_idle_loop_hook(void);
 
 	smtc_idle_loop_hook();
 #endif
-
-			if (cpu_wait) {
-				/* Don't trace irqs off for idle */
-				stop_critical_timings();
+	if (cpu_wait)
 		(*cpu_wait)();
-				start_critical_timings();
-			}
-		}
-#ifdef CONFIG_HOTPLUG_CPU
-		if (!cpu_online(cpu) && !cpu_isset(cpu, cpu_callin_map))
-			play_dead();
-#endif
-		rcu_idle_exit();
-		tick_nohz_idle_exit();
-		schedule_preempt_disabled();
-	}
+	else
+		local_irq_enable();
 }
 
 asmlinkage void ret_from_fork(void);

arch/mips/kernel/smp.c

@@ -139,7 +139,7 @@ asmlinkage __cpuinit void start_secondary(void)
 	WARN_ON_ONCE(!irqs_disabled());
 	mp_ops->smp_finish();
 
-	cpu_idle();
+	cpu_startup_entry(CPUHP_ONLINE);
 }
 
 /*