Sometimes I see rcu_urgent_qs is not set. This could be when the last IPI was a long time ago, however, the grace period just started. Set rcu_urgent_qs so the tick can indeed be stopped. Signed-off-by: Joel Fernandes (Google) <joel@xxxxxxxxxxxxxxxxx> --- kernel/rcu/tree.c | 1 + 1 file changed, 1 insertion(+) diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 322b1b57967c..856d3c9f1955 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -1091,6 +1091,7 @@ static int rcu_implicit_dynticks_qs(struct rcu_data *rdp) if (tick_nohz_full_cpu(rdp->cpu) && time_after(jiffies, READ_ONCE(rdp->last_fqs_resched) + jtsq * 3)) { + WRITE_ONCE(*ruqp, true); resched_cpu(rdp->cpu); WRITE_ONCE(rdp->last_fqs_resched, jiffies); } -- 2.23.0.rc1.153.gdeed80330f-goog