rcu/nocb: Cancel nocb_timer upon nocb_gp wakeup

When waking up in nocb_gp_wait(), there is no need to keep the nocb_timer
around because this function will traverse the whole rdp list. Any
update performed before the timer was armed will now be visible after
the ->nocb_gp_lock acquire.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Neeraj Upadhyay <neeraju@codeaurora.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit is contained in:
Frederic Weisbecker 2021-02-23 01:10:07 +01:00 committed by Paul E. McKenney
parent 552cac80e6
commit b6e2c4ed35
1 changed files with 4 additions and 0 deletions

View File

@ -2211,6 +2211,10 @@ static void nocb_gp_wait(struct rcu_data *my_rdp)
raw_spin_lock_irqsave(&my_rdp->nocb_gp_lock, flags);
if (bypass)
del_timer(&my_rdp->nocb_bypass_timer);
if (my_rdp->nocb_defer_wakeup > RCU_NOCB_WAKE_NOT) {
WRITE_ONCE(my_rdp->nocb_defer_wakeup, RCU_NOCB_WAKE_NOT);
del_timer(&my_rdp->nocb_timer);
}
WRITE_ONCE(my_rdp->nocb_gp_sleep, true);
raw_spin_unlock_irqrestore(&my_rdp->nocb_gp_lock, flags);
}