From f75044a4bcfd04bc14b9b458a7819c2ce2dff967 Mon Sep 17 00:00:00 2001 From: Frederic Weisbecker Date: Tue, 23 Feb 2021 01:10:05 +0100 Subject: [PATCH] rcu/nocb: Directly call __wake_nocb_gp() from bypass timer The bypass timer calls __call_rcu_nocb_wake() instead of directly calling __wake_nocb_gp(). The only difference here is that rdp->qlen_last_fqs_check gets overriden. But resetting the deferred force quiescent state base shouldn't be relevant for that timer. In fact the bypass queue in question can be for any rdp from the group and not necessarily the rdp leader on which the bypass timer is attached. This commit therefore calls __wake_nocb_gp() directly. This way we don't even need to lock the ->nocb_lock. Signed-off-by: Frederic Weisbecker Cc: Josh Triplett Cc: Lai Jiangshan Cc: Joel Fernandes Cc: Neeraj Upadhyay Cc: Boqun Feng Signed-off-by: Paul E. McKenney --- kernel/rcu/tree_plugin.h | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h index 5a2aa9c4e569..82e9ffb92347 100644 --- a/kernel/rcu/tree_plugin.h +++ b/kernel/rcu/tree_plugin.h @@ -2015,9 +2015,10 @@ static void do_nocb_bypass_wakeup_timer(struct timer_list *t) struct rcu_data *rdp = from_timer(rdp, t, nocb_bypass_timer); trace_rcu_nocb_wake(rcu_state.name, rdp->cpu, TPS("Timer")); - rcu_nocb_lock_irqsave(rdp, flags); + + raw_spin_lock_irqsave(&rdp->nocb_gp_lock, flags); smp_mb__after_spinlock(); /* Timer expire before wakeup. */ - __call_rcu_nocb_wake(rdp, true, flags); + __wake_nocb_gp(rdp, rdp, false, flags); } /* -- 2.50.1