From fd2ac4f4a65a7f34b0bc6433fcca1192d7ba8b8e Mon Sep 17 00:00:00 2001 From: Frederic Weisbecker Date: Tue, 18 Mar 2014 21:12:53 +0100 Subject: [PATCH] nohz: Use nohz own full kick on 2nd task enqueue Now that we have a nohz full remote kick based on irq work, lets use it to notify a CPU that it's exiting single task mode. This unbloats a bit the scheduler IPI that the nohz code was abusing for its cool "callable anywhere/anytime" properties. Acked-by: Peter Zijlstra Cc: Andrew Morton Cc: Ingo Molnar Cc: Kevin Hilman Cc: Paul E. McKenney Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Viresh Kumar Signed-off-by: Frederic Weisbecker --- kernel/sched/core.c | 5 +---- kernel/sched/sched.h | 2 +- 2 files changed, 2 insertions(+), 5 deletions(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index feb54965e16f..13f5857a15ba 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -1574,9 +1574,7 @@ void scheduler_ipi(void) */ preempt_fold_need_resched(); - if (llist_empty(&this_rq()->wake_list) - && !tick_nohz_full_cpu(smp_processor_id()) - && !got_nohz_idle_kick()) + if (llist_empty(&this_rq()->wake_list) && !got_nohz_idle_kick()) return; /* @@ -1593,7 +1591,6 @@ void scheduler_ipi(void) * somewhat pessimize the simple resched case. */ irq_enter(); - tick_nohz_full_check(); sched_ttwu_pending(); /* diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index 31cc02ebc54e..599a72aff5ea 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -1223,7 +1223,7 @@ static inline void add_nr_running(struct rq *rq, unsigned count) if (tick_nohz_full_cpu(rq->cpu)) { /* Order rq->nr_running write against the IPI */ smp_wmb(); - smp_send_reschedule(rq->cpu); + tick_nohz_full_kick_cpu(rq->cpu); } } #endif -- 2.20.1