From: "Rafael J. Wysocki" <rjw@rjwysocki.net>
To: Frederic Weisbecker <frederic@kernel.org>
Cc: Linux PM <linux-pm@vger.kernel.org>,
Peter Zijlstra <peterz@infradead.org>,
Frederic Weisbecker <fweisbec@gmail.com>,
Thomas Gleixner <tglx@linutronix.de>,
Paul McKenney <paulmck@linux.vnet.ibm.com>,
Thomas Ilsche <thomas.ilsche@tu-dresden.de>,
Doug Smythies <dsmythies@telus.net>,
Rik van Riel <riel@surriel.com>,
Aubrey Li <aubrey.li@linux.intel.com>,
Mike Galbraith <mgalbraith@suse.de>,
LKML <linux-kernel@vger.kernel.org>,
Len Brown <len.brown@intel.com>
Subject: Re: [PATCH v9 06/10] time: tick-sched: Split tick_nohz_stop_sched_tick()
Date: Sat, 07 Apr 2018 18:36:34 +0200 [thread overview]
Message-ID: <2792573.Q2KagqXIrf@aspire.rjw.lan> (raw)
In-Reply-To: <20180407023623.GA16600@lerouge>
On Saturday, April 7, 2018 4:36:25 AM CEST Frederic Weisbecker wrote:
> On Wed, Apr 04, 2018 at 10:41:13AM +0200, Rafael J. Wysocki wrote:
> > From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> >
> > In order to address the issue with short idle duration predictions
> > by the idle governor after the scheduler tick has been stopped, split
> > tick_nohz_stop_sched_tick() into two separate routines, one computing
> > the time to the next timer event and the other simply stopping the
> > tick when the time to the next timer event is known.
> >
> > Prepare these two routines to be called separately, as one of them
> > will be called by the idle governor in the cpuidle_select() code
> > path after subsequent changes.
> >
> > Update the former callers of tick_nohz_stop_sched_tick() to use
> > the new routines, tick_nohz_next_event() and tick_nohz_stop_tick(),
> > instead of it and move the updates of the sleep_length field in
> > struct tick_sched into __tick_nohz_idle_stop_tick() as it doesn't
> > need to be updated anywhere else.
> >
> > There should be no intentional visible changes in functionality
> > resulting from this change.
> >
> > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
>
> Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
>
> Thanks! And sorry for the slow reviews, the changes are sensitive
Right, very much so.
> and I want to make sure we are not breaking some subtlety.
Thanks a lot for doing that!
next prev parent reply other threads:[~2018-04-07 16:36 UTC|newest]
Thread overview: 40+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-04-04 8:32 [PATCH v9 00/10] sched/cpuidle: Idle loop rework Rafael J. Wysocki
2018-04-04 8:33 ` [PATCH v9 01/10] time: tick-sched: Reorganize idle tick management code Rafael J. Wysocki
2018-04-04 8:34 ` [PATCH v9 02/10] sched: idle: Do not stop the tick upfront in the idle loop Rafael J. Wysocki
2018-04-04 8:36 ` [PATCH v9 03/10] sched: idle: Do not stop the tick before cpuidle_idle_call() Rafael J. Wysocki
2018-04-04 8:38 ` [PATCH v9 04/10] jiffies: Introduce USER_TICK_USEC and redefine TICK_USEC Rafael J. Wysocki
2018-04-06 1:09 ` Frederic Weisbecker
2018-04-06 7:20 ` Rafael J. Wysocki
2018-04-04 8:39 ` [PATCH v9 05/10] cpuidle: Return nohz hint from cpuidle_select() Rafael J. Wysocki
2018-04-06 2:44 ` Frederic Weisbecker
2018-04-06 7:24 ` Rafael J. Wysocki
2018-04-06 14:19 ` Frederic Weisbecker
2018-04-06 7:58 ` Peter Zijlstra
2018-04-06 14:23 ` Frederic Weisbecker
2018-04-06 8:11 ` Rafael J. Wysocki
2018-04-06 12:56 ` Rafael J. Wysocki
2018-04-06 15:28 ` Frederic Weisbecker
2018-04-06 14:28 ` Frederic Weisbecker
2018-04-04 8:41 ` [PATCH v9 06/10] time: tick-sched: Split tick_nohz_stop_sched_tick() Rafael J. Wysocki
2018-04-07 2:36 ` Frederic Weisbecker
2018-04-07 16:36 ` Rafael J. Wysocki [this message]
2018-04-04 8:45 ` [PATCH v9 07/10] time: hrtimer: Introduce hrtimer_next_event_without() Rafael J. Wysocki
2018-04-07 14:46 ` Frederic Weisbecker
2018-04-08 8:20 ` Rafael J. Wysocki
2018-04-08 17:58 ` Frederic Weisbecker
2018-04-04 8:47 ` [PATCH v9 08/10] sched: idle: Select idle state before stopping the tick Rafael J. Wysocki
2018-04-09 2:41 ` Frederic Weisbecker
2018-04-04 8:49 ` [PATCH v9 09/10] cpuidle: menu: Refine idle state selection for running tick Rafael J. Wysocki
2018-04-05 12:27 ` Peter Zijlstra
2018-04-05 13:51 ` Rafael J. Wysocki
2018-04-05 12:32 ` Peter Zijlstra
2018-04-05 13:52 ` Rafael J. Wysocki
2018-04-04 8:50 ` [PATCH v9 10/10] cpuidle: menu: Avoid selecting shallow states with stopped tick Rafael J. Wysocki
2018-04-05 12:47 ` Peter Zijlstra
2018-04-05 13:49 ` Rafael J. Wysocki
2018-04-05 14:11 ` Peter Zijlstra
2018-04-05 14:13 ` Peter Zijlstra
2018-04-05 14:29 ` Rafael J. Wysocki
2018-04-08 16:32 ` [PATCH v9 00/10] sched/cpuidle: Idle loop rework Rafael J. Wysocki
2018-04-09 15:58 ` Thomas Ilsche
2018-04-10 7:03 ` Rafael J. Wysocki
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