While we enqueue a new timer on a dynticks target, we must send it an IPI so that it reschedules the next tick accordingly.
Now all we need for that is to run irq_exit() on the target. Hence an empty IRQ is way enough. We don't need to run tick_nohz_full_check() and all the overhead that comes with the several cmpxchg() necessary for irq work list and state progress. So lets use a void irq work instead. Cc: Ingo Molnar <[email protected]> Cc: Paul E. McKenney <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Steven Rostedt <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Viresh Kumar <[email protected]> Signed-off-by: Frederic Weisbecker <[email protected]> --- kernel/sched/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 7f3063c..f3e48b8 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -693,7 +693,7 @@ static bool wake_up_full_nohz_cpu(int cpu) if (tick_nohz_full_cpu(cpu)) { if (cpu != smp_processor_id() || tick_nohz_tick_stopped()) - tick_nohz_full_kick_cpu(cpu); + irq_work_void_on(cpu); return true; } -- 1.8.3.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
