Messages in this thread Patch in this message | | | Date | Wed, 30 Jun 2021 13:47:29 -0000 | From | "tip-bot2 for Frederic Weisbecker" <> | Subject | [tip: core/rcu] rcu/nocb: Cancel nocb_timer upon nocb_gp wakeup |
| |
The following commit has been merged into the core/rcu branch of tip:
Commit-ID: b6e2c4ed35c33d7e55197aa26d99645a690ca467 Gitweb: https://git.kernel.org/tip/b6e2c4ed35c33d7e55197aa26d99645a690ca467 Author: Frederic Weisbecker <frederic@kernel.org> AuthorDate: Tue, 23 Feb 2021 01:10:07 +01:00 Committer: Paul E. McKenney <paulmck@kernel.org> CommitterDate: Wed, 12 May 2021 12:10:23 -07:00
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> --- kernel/rcu/tree_plugin.h | 4 ++++ 1 file changed, 4 insertions(+)
diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h index 015adec..a667551 100644 --- a/kernel/rcu/tree_plugin.h +++ b/kernel/rcu/tree_plugin.h @@ -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); }
| |