From: Uladzislau Rezki <urezki@gmail.com>
To: paulmck@kernel.org, "Joel Fernandes (Google)" <joel@joelfernandes.org>
Cc: rcu@vger.kernel.org, linux-kernel@vger.kernel.org,
rushikesh.s.kadam@intel.com, urezki@gmail.com,
neeraj.iitr10@gmail.com, frederic@kernel.org, paulmck@kernel.org,
rostedt@goodmis.org, youssefesmat@google.com, surenb@google.com
Subject: Re: [PATCH v7 02/11] rcu: Make call_rcu() lazy to save power
Date: Tue, 4 Oct 2022 13:41:38 +0200 [thread overview]
Message-ID: <Yzwb8vgYhAvDJzK+@pc636> (raw)
In-Reply-To: <20221004024157.2470238-3-joel@joelfernandes.org>
> trace_rcu_nocb_wake(rcu_state.name, rdp->cpu, TPS("Check"));
> rcu_nocb_lock_irqsave(rdp, flags);
> lockdep_assert_held(&rdp->nocb_lock);
> bypass_ncbs = rcu_cblist_n_cbs(&rdp->nocb_bypass);
> - if (bypass_ncbs &&
> + lazy_ncbs = READ_ONCE(rdp->lazy_len);
> +
> + if (bypass_ncbs && (lazy_ncbs == bypass_ncbs) &&
> + (time_after(j, READ_ONCE(rdp->nocb_bypass_first) + jiffies_till_flush) ||
> + bypass_ncbs > 2 * qhimark)) {
Do you know why we want double "qhimark" threshold? It is not only this
place, there are several. I am asking because it is not expected by the
user.
--
Uladzsislau Rezki
next prev parent reply other threads:[~2022-10-04 11:41 UTC|newest]
Thread overview: 45+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-10-04 2:41 [PATCH v7 00/11] rcu: call_rcu() power improvements Joel Fernandes (Google)
2022-10-04 2:41 ` [PATCH v7 01/11] rcu: Wake up nocb gp thread on rcu_barrier_entrain() Joel Fernandes (Google)
2022-10-04 22:28 ` Frederic Weisbecker
2022-10-04 22:57 ` Joel Fernandes
2022-10-05 10:39 ` Frederic Weisbecker
2022-10-07 2:47 ` Joel Fernandes
2022-10-07 11:26 ` Frederic Weisbecker
2022-10-07 12:46 ` Joel Fernandes
2022-10-04 2:41 ` [PATCH v7 02/11] rcu: Make call_rcu() lazy to save power Joel Fernandes (Google)
2022-10-04 11:41 ` Uladzislau Rezki [this message]
2022-10-04 13:30 ` Paul E. McKenney
2022-10-04 14:53 ` Uladzislau Rezki
2022-10-04 15:58 ` Paul E. McKenney
2022-10-04 16:20 ` Uladzislau Rezki
2022-10-04 18:27 ` Paul E. McKenney
2022-10-05 11:28 ` Uladzislau Rezki
2022-10-04 16:22 ` Joel Fernandes
2022-10-04 18:05 ` Joel Fernandes
2022-10-05 11:21 ` Uladzislau Rezki
2022-10-05 11:44 ` Uladzislau Rezki
2022-10-06 19:11 ` Paul E. McKenney
2022-10-11 17:44 ` Joel Fernandes
2022-10-04 2:41 ` [PATCH v7 03/11] rcu: Refactor code a bit in rcu_nocb_do_flush_bypass() Joel Fernandes (Google)
2022-10-06 19:12 ` Paul E. McKenney
2022-10-04 2:41 ` [PATCH v7 04/11] rcu: shrinker for lazy rcu Joel Fernandes (Google)
2022-10-04 2:41 ` [PATCH v7 05/11] rcuscale: Add laziness and kfree tests Joel Fernandes (Google)
2022-10-06 19:15 ` Paul E. McKenney
2022-10-04 2:41 ` [PATCH v7 06/11] percpu-refcount: Use call_rcu_flush() for atomic switch Joel Fernandes (Google)
2022-10-04 2:41 ` [PATCH v7 07/11] rcu/sync: Use call_rcu_flush() instead of call_rcu Joel Fernandes (Google)
2022-10-04 2:41 ` [PATCH v7 08/11] rcu/rcuscale: Use call_rcu_flush() for async reader test Joel Fernandes (Google)
2022-10-04 2:41 ` [PATCH v7 09/11] rcu/rcutorture: Use call_rcu_flush() where needed Joel Fernandes (Google)
2022-10-04 2:41 ` [PATCH v7 10/11] scsi/scsi_error: Use call_rcu_flush() instead of call_rcu() Joel Fernandes (Google)
2022-10-07 3:18 ` Joel Fernandes
2022-10-07 17:19 ` Joel Fernandes
2022-10-07 17:31 ` Joel Fernandes
2022-10-07 17:52 ` Paul E. McKenney
2022-10-07 19:29 ` Joel Fernandes
2022-10-07 19:56 ` Paul E. McKenney
2022-10-07 20:24 ` Joel Fernandes
2022-10-04 2:41 ` [PATCH v7 11/11] workqueue: Make queue_rcu_work() use call_rcu_flush() Joel Fernandes (Google)
2022-10-06 18:55 ` [PATCH v7 00/11] rcu: call_rcu() power improvements Paul E. McKenney
2022-10-07 14:40 ` Uladzislau Rezki
2022-10-07 14:54 ` Paul E. McKenney
2022-10-07 15:09 ` Joel Fernandes
2022-10-07 18:30 ` Paul E. McKenney
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