Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull SMP/hotplug changes from Ingo Molnar:
 "This is a pretty large, multi-arch series unifying and generalizing
  the various disjunct pieces of idle routines that architectures have
  historically copied from each other and have grown in random, wildly
  inconsistent and sometimes buggy directions:

   101 files changed, 455 insertions(+), 1328 deletions(-)

  this went through a number of review and test iterations before it was
  committed, it was tested on various architectures, was exposed to
  linux-next for quite some time - nevertheless it might cause problems
  on architectures that don't read the mailing lists and don't regularly
  test linux-next.

  This cat herding excercise was motivated by the -rt kernel, and was
  brought to you by Thomas "the Whip" Gleixner."

* 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (40 commits)
  idle: Remove GENERIC_IDLE_LOOP config switch
  um: Use generic idle loop
  ia64: Make sure interrupts enabled when we "safe_halt()"
  sparc: Use generic idle loop
  idle: Remove unused ARCH_HAS_DEFAULT_IDLE
  bfin: Fix typo in arch_cpu_idle()
  xtensa: Use generic idle loop
  x86: Use generic idle loop
  unicore: Use generic idle loop
  tile: Use generic idle loop
  tile: Enter idle with preemption disabled
  sh: Use generic idle loop
  score: Use generic idle loop
  s390: Use generic idle loop
  powerpc: Use generic idle loop
  parisc: Use generic idle loop
  openrisc: Use generic idle loop
  mn10300: Use generic idle loop
  mips: Use generic idle loop
  microblaze: Use generic idle loop
  ...

arch/cris/arch-v10/kernel/process.c

@@ -30,8 +30,9 @@ void etrax_gpio_wake_up_check(void); /* drivers/gpio.c */
 void default_idle(void)
 {
 #ifdef CONFIG_ETRAX_GPIO
-  etrax_gpio_wake_up_check();
+	etrax_gpio_wake_up_check();
 #endif
+	local_irq_enable();
 }
 
 /*

arch/cris/arch-v32/kernel/process.c

@@ -20,18 +20,12 @@
 
 extern void stop_watchdog(void);
 
-extern int cris_hlt_counter;
-
 /* We use this if we don't have any better idle routine. */
 void default_idle(void)
 {
-	local_irq_disable();
-	if (!need_resched() && !cris_hlt_counter) {
-	        /* Halt until exception. */
-		__asm__ volatile("ei    \n\t"
-                                 "halt      ");
-	}
-	local_irq_enable();
+	/* Halt until exception. */
+	__asm__ volatile("ei    \n\t"
+			 "halt      ");
 }
 
 /*

arch/cris/arch-v32/kernel/smp.c

@@ -145,8 +145,6 @@ smp_boot_one_cpu(int cpuid, struct task_struct idle)
  * specific stuff such as the local timer and the MMU. */
 void __init smp_callin(void)
 {
-	extern void cpu_idle(void);
-
 	int cpu = cpu_now_booting;
 	reg_intr_vect_rw_mask vect_mask = {0};
 
@@ -170,7 +168,7 @@ void __init smp_callin(void)
 	local_irq_enable();
 
 	set_cpu_online(cpu, true);
-	cpu_idle();
+	cpu_startup_entry(CPUHP_ONLINE);
 }
 
 /* Stop execution on this CPU.*/

arch/cris/include/asm/processor.h

@@ -65,13 +65,6 @@ static inline void release_thread(struct task_struct *dead_task)
 
 #define cpu_relax()     barrier()
 
-/*
- * disable hlt during certain critical i/o operations
- */
-#define HAVE_DISABLE_HLT
-void disable_hlt(void);
-void enable_hlt(void);
-
 void default_idle(void);
 
 #endif /* __ASM_CRIS_PROCESSOR_H */

arch/cris/kernel/process.c

@@ -29,59 +29,14 @@
 
 //#define DEBUG
 
-/*
- * The hlt_counter, disable_hlt and enable_hlt is just here as a hook if
- * there would ever be a halt sequence (for power save when idle) with
- * some largish delay when halting or resuming *and* a driver that can't
- * afford that delay.  The hlt_counter would then be checked before
- * executing the halt sequence, and the driver marks the unhaltable
- * region by enable_hlt/disable_hlt.
- */
-
-int cris_hlt_counter=0;
-
-void disable_hlt(void)
-{
-	cris_hlt_counter++;
-}
-
-EXPORT_SYMBOL(disable_hlt);
-
-void enable_hlt(void)
-{
-	cris_hlt_counter--;
-}
-
-EXPORT_SYMBOL(enable_hlt);
- 
 extern void default_idle(void);
 
 void (*pm_power_off)(void);
 EXPORT_SYMBOL(pm_power_off);
 
-/*
- * 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 cpu_idle (void)
+void arch_cpu_idle(void)
 {
-	/* endless idle loop with no priority at all */
-	while (1) {
-		rcu_idle_enter();
-		while (!need_resched()) {
-			/*
-			 * Mark this as an RCU critical section so that
-			 * synchronize_kernel() in the unload path waits
-			 * for our completion.
-			 */
-			default_idle();
-		}
-		rcu_idle_exit();
-		schedule_preempt_disabled();
-	}
+	default_idle();
 }
 
 void hard_reset_now (void);