idle: Implement set/clr functions for need_resched poll

Implement set/clear functions for the idle need_resched poll
implementation.

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>
Link: http://lkml.kernel.org/r/20130321215233.518839807@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

include/linux/sched.h

@@ -2632,13 +2632,34 @@ static inline int tsk_is_polling(struct task_struct *p)
 {
 	return task_thread_info(p)->status & TS_POLLING;
 }
+static inline void current_set_polling(void)
+{
+	current_thread_info()->status |= TS_POLLING;
+}
+
+static inline void current_clr_polling(void)
+{
+	current_thread_info()->status &= ~TS_POLLING;
+	smp_mb__after_clear_bit();
+}
 #elif defined(TIF_POLLING_NRFLAG)
 static inline int tsk_is_polling(struct task_struct *p)
 {
 	return test_tsk_thread_flag(p, TIF_POLLING_NRFLAG);
 }
+static inline void current_set_polling(void)
+{
+	set_thread_flag(TIF_POLLING_NRFLAG);
+}
+
+static inline void current_clr_polling(void)
+{
+	clear_thread_flag(TIF_POLLING_NRFLAG);
+}
 #else
 static inline int tsk_is_polling(struct task_struct *p) { return 0; }
+static inline void current_set_polling(void) { }
+static inline void current_clr_polling(void) { }
 #endif
 
 /*