All of lore.kernel.org
 help / color / mirror / Atom feed
From: Morten Rasmussen <morten.rasmussen@arm.com>
To: Catalin Marinas <catalin.marinas@arm.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>,
	Peter Zijlstra <peterz@infradead.org>,
	Vincent Guittot <vincent.guittot@linaro.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Ingo Molnar <mingo@kernel.org>, Paul Turner <pjt@google.com>,
	Chris Metcalf <cmetcalf@tilera.com>,
	Tony Luck <tony.luck@intel.com>,
	"alex.shi@intel.com" <alex.shi@intel.com>,
	Preeti U Murthy <preeti@linux.vnet.ibm.com>,
	linaro-kernel <linaro-kernel@lists.linaro.org>,
	"len.brown@intel.com" <len.brown@intel.com>,
	"l.majewski@samsung.com" <l.majewski@samsung.com>,
	Jonathan Corbet <corbet@lwn.net>,
	"Rafael J. Wysocki" <rjw@sisk.pl>,
	Paul McKenney <paulmck@linux.vnet.ibm.com>,
	"linux-pm@vger.kernel.org" <linux-pm@vger.kernel.org>
Subject: Re: [RFC][PATCH v5 00/14] sched: packing tasks
Date: Tue, 12 Nov 2013 12:06:34 +0000	[thread overview]
Message-ID: <20131112120634.GA5762@e103034-lin> (raw)
In-Reply-To: <20131111181805.GE29572@arm.com>

On Mon, Nov 11, 2013 at 06:18:05PM +0000, Catalin Marinas wrote:
> On Mon, Nov 11, 2013 at 04:39:45PM +0000, Arjan van de Ven wrote:
> > having a hardware driver give a prefered CPU ordering for wakes can indeed be useful.
> > (I'm doubtful that changing the recommendation for each idle is going to pay off,
> > but proof is in the pudding; there are certainly long term effects where this can help)
> 
> The ordering is based on the actual C-state, so a simple way is to wake
> up the CPU in the shallowest C-state. With asymmetric configurations
> (big.LITTLE) we have different costs for the same C-state, so this would
> come in handy.

Asymmetric configurations add a bit of extra fun to deal with as you
don't want to pick the cpu in the shallowest C-state if it is the wrong
type of cpu for the task waking up. That goes for both big and little
cpus in big.LITTLE.

So the hardware driver would need to know which cpus that are suitable
targets for the task, or we need to somehow limit the driver query to
suitable cpus, or the driver should return a list of cpus guaranteed to
include cpus of all types (big, little, whatever...).

Morten

  parent reply	other threads:[~2013-11-12 12:07 UTC|newest]

Thread overview: 101+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-10-18 11:52 [RFC][PATCH v5 00/14] sched: packing tasks Vincent Guittot
2013-10-18 11:52 ` [RFC][PATCH v5 01/14] sched: add a new arch_sd_local_flags for sched_domain init Vincent Guittot
2013-11-05 14:06   ` Peter Zijlstra
2013-11-05 14:57     ` Vincent Guittot
2013-11-05 22:27       ` Peter Zijlstra
2013-11-06 10:10         ` Vincent Guittot
2013-11-06 13:53         ` Martin Schwidefsky
2013-11-06 14:08           ` Peter Zijlstra
2013-11-12 17:43             ` Dietmar Eggemann
2013-11-12 18:08               ` Peter Zijlstra
2013-11-13 15:47                 ` Dietmar Eggemann
2013-11-13 16:29                   ` Peter Zijlstra
2013-11-14 10:49                     ` Morten Rasmussen
2013-11-14 12:07                       ` Peter Zijlstra
2013-12-18 13:13         ` [RFC] sched: CPU topology try Vincent Guittot
2013-12-23 17:22           ` Dietmar Eggemann
2014-01-06 13:41             ` Vincent Guittot
2014-01-06 16:31               ` Peter Zijlstra
2014-01-07  8:32                 ` Vincent Guittot
2014-01-07 13:22                   ` Peter Zijlstra
2014-01-07 14:10                     ` Peter Zijlstra
2014-01-07 15:41                       ` Morten Rasmussen
2014-01-07 20:49                         ` Peter Zijlstra
2014-01-08  8:32                           ` Alex Shi
2014-01-08  8:37                             ` Peter Zijlstra
2014-01-08 12:52                               ` Morten Rasmussen
2014-01-08 13:04                                 ` Peter Zijlstra
2014-01-08 13:33                                   ` Morten Rasmussen
2014-01-08 12:35                           ` Morten Rasmussen
2014-01-08 12:42                             ` Peter Zijlstra
2014-01-08 12:45                             ` Peter Zijlstra
2014-01-08 13:27                               ` Morten Rasmussen
2014-01-08 13:32                                 ` Peter Zijlstra
2014-01-08 13:45                                   ` Morten Rasmussen
2014-01-07 14:11                     ` Vincent Guittot
2014-01-07 15:37                       ` Morten Rasmussen
2014-01-08  8:37                         ` Alex Shi
2014-01-06 16:28             ` Peter Zijlstra
2014-01-06 17:15               ` Morten Rasmussen
2014-01-07  9:57                 ` Peter Zijlstra
2014-01-01  5:00           ` Preeti U Murthy
2014-01-06 16:33             ` Peter Zijlstra
2014-01-06 16:37               ` Arjan van de Ven
2014-01-06 16:48                 ` Peter Zijlstra
2014-01-06 16:54                   ` Peter Zijlstra
2014-01-06 17:13                     ` Arjan van de Ven
2014-01-07 12:40             ` Vincent Guittot
2014-01-06 16:21           ` Peter Zijlstra
2014-01-07  8:22             ` Vincent Guittot
2014-01-07  9:40           ` Preeti U Murthy
2014-01-07  9:50             ` Peter Zijlstra
2014-01-07 10:39               ` Preeti U Murthy
2014-01-07 11:13                 ` Peter Zijlstra
2014-01-07 16:31                   ` Preeti U Murthy
2014-01-07 11:20                 ` Morten Rasmussen
2014-01-07 12:31                 ` Vincent Guittot
2014-01-07 16:51                   ` Preeti U Murthy
2013-10-18 11:52 ` [RFC][PATCH v5 03/14] sched: define pack buddy CPUs Vincent Guittot
2013-10-18 11:52 ` [RFC][PATCH v5 04/14] sched: do load balance only with packing cpus Vincent Guittot
2013-10-18 11:52 ` [RFC][PATCH v5 05/14] sched: add a packing level knob Vincent Guittot
2013-11-12 10:32   ` Peter Zijlstra
2013-11-12 10:44     ` Vincent Guittot
2013-11-12 10:55       ` Peter Zijlstra
2013-11-12 10:57         ` Vincent Guittot
2013-10-18 11:52 ` [RFC][PATCH v5 06/14] sched: create a new field with available capacity Vincent Guittot
2013-11-12 10:34   ` Peter Zijlstra
2013-11-12 11:05     ` Vincent Guittot
2013-10-18 11:52 ` [RFC][PATCH v5 07/14] sched: get CPU's activity statistic Vincent Guittot
2013-11-12 10:36   ` Peter Zijlstra
2013-11-12 10:41   ` Peter Zijlstra
2013-10-18 11:52 ` [RFC][PATCH v5 08/14] sched: move load idx selection in find_idlest_group Vincent Guittot
2013-11-12 10:49   ` Peter Zijlstra
2013-11-27 14:10   ` [tip:sched/core] sched/fair: Move " tip-bot for Vincent Guittot
2013-10-18 11:52 ` [RFC][PATCH v5 09/14] sched: update the packing cpu list Vincent Guittot
2013-10-18 11:52 ` [RFC][PATCH v5 10/14] sched: init this_load to max in find_idlest_group Vincent Guittot
2013-10-18 11:52 ` [RFC][PATCH v5 11/14] sched: add a SCHED_PACKING_TASKS config Vincent Guittot
2013-10-18 11:52 ` [RFC][PATCH v5 12/14] sched: create a statistic structure Vincent Guittot
2013-10-18 11:52 ` [RFC][PATCH v5 13/14] sched: differantiate idle cpu Vincent Guittot
2013-10-18 11:52 ` [RFC][PATCH v5 14/14] cpuidle: set the current wake up latency Vincent Guittot
2013-11-11 11:33 ` [RFC][PATCH v5 00/14] sched: packing tasks Catalin Marinas
2013-11-11 16:36   ` Peter Zijlstra
2013-11-11 16:39     ` Arjan van de Ven
2013-11-11 18:18       ` Catalin Marinas
2013-11-11 18:20         ` Arjan van de Ven
2013-11-12 12:06         ` Morten Rasmussen [this message]
2013-11-12 16:48         ` Arjan van de Ven
2013-11-12 23:14           ` Catalin Marinas
2013-11-13 16:13             ` Arjan van de Ven
2013-11-13 16:45               ` Catalin Marinas
2013-11-13 17:56                 ` Arjan van de Ven
2013-11-12 17:40     ` Catalin Marinas
2013-11-25 18:55     ` Daniel Lezcano
2013-11-11 16:38   ` Peter Zijlstra
2013-11-11 16:40     ` Arjan van de Ven
2013-11-12 10:36     ` Vincent Guittot
2013-11-11 16:54   ` Morten Rasmussen
2013-11-11 18:31     ` Catalin Marinas
2013-11-11 19:26       ` Arjan van de Ven
2013-11-11 22:43         ` Nicolas Pitre
2013-11-11 23:43         ` Catalin Marinas
2013-11-12 12:35   ` Vincent Guittot

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20131112120634.GA5762@e103034-lin \
    --to=morten.rasmussen@arm.com \
    --cc=alex.shi@intel.com \
    --cc=arjan@linux.intel.com \
    --cc=catalin.marinas@arm.com \
    --cc=cmetcalf@tilera.com \
    --cc=corbet@lwn.net \
    --cc=l.majewski@samsung.com \
    --cc=len.brown@intel.com \
    --cc=linaro-kernel@lists.linaro.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pm@vger.kernel.org \
    --cc=mingo@kernel.org \
    --cc=paulmck@linux.vnet.ibm.com \
    --cc=peterz@infradead.org \
    --cc=pjt@google.com \
    --cc=preeti@linux.vnet.ibm.com \
    --cc=rjw@sisk.pl \
    --cc=tony.luck@intel.com \
    --cc=vincent.guittot@linaro.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.