nohz: Disable the tick when irq resume in full dynticks CPU

Eventually try to disable tick on irq exit, now that the
fundamental infrastructure is in place.

Signed-off-by: Frederic Weisbecker <[email protected]>
Cc: Chris Metcalf <[email protected]>
Cc: Christoph Lameter <[email protected]>
Cc: Geoff Levand <[email protected]>
Cc: Gilad Ben Yossef <[email protected]>
Cc: Hakan Akkan <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Kevin Hilman <[email protected]>
Cc: Li Zhong <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Cc: Paul E. McKenney <[email protected]>
Cc: Paul Gortmaker <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Thomas Gleixner <[email protected]>

1 files changed, 14 insertions, 5 deletions

diff --git a/kernel/softirq.c b/kernel/softirq.c
index de15813f2a66..8b1446d4a4db 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -337,6 +337,19 @@ static inline void invoke_softirq(void)
 	}
 }
 
+static inline void tick_irq_exit(void)
+{
+#ifdef CONFIG_NO_HZ_COMMON
+	int cpu = smp_processor_id();
+
+	/* Make sure that timer wheel updates are propagated */
+	if ((idle_cpu(cpu) && !need_resched()) || tick_nohz_full_cpu(cpu)) {
+		if (!in_interrupt())
+			tick_nohz_irq_exit();
+	}
+#endif
+}
+
 /*
  * Exit an interrupt context. Process softirqs if needed and possible:
  */
@@ -348,11 +361,7 @@ void irq_exit(void)
 	if (!in_interrupt() && local_softirq_pending())
 		invoke_softirq();
 
-#ifdef CONFIG_NO_HZ_COMMON
-	/* Make sure that timer wheel updates are propagated */
-	if (idle_cpu(smp_processor_id()) && !in_interrupt() && !need_resched())
-		tick_nohz_irq_exit();
-#endif
+	tick_irq_exit();
 	rcu_irq_exit();
 	sched_preempt_enable_no_resched();
 }