public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Peter Zijlstra <peterz@infradead.org>
To: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: LKML <linux-kernel@vger.kernel.org>,
	Rafael Wysocki <rafael.j.wysocki@intel.com>,
	Len Brown <len.brown@intel.com>,
	Andi Kleen <andi.kleen@intel.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Paul Turner <pjt@google.com>,
	Tim Chen <tim.c.chen@linux.intel.com>,
	Dietmar Eggemann <dietmar.eggemann@arm.com>,
	Eduardo Valentin <edubezval@gmail.com>,
	Punit Agrawal <punit.agrawal@arm.com>,
	Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Subject: Re: [RFC PATCH v2 3/3] sched: introduce synchronized idle injection
Date: Tue, 10 Nov 2015 15:58:23 +0100	[thread overview]
Message-ID: <20151110145823.GD17308@twins.programming.kicks-ass.net> (raw)
In-Reply-To: <20151110060116.26cd5ff8@yairi>

On Tue, Nov 10, 2015 at 06:01:16AM -0800, Jacob Pan wrote:
> On Tue, 10 Nov 2015 14:23:24 +0100
> Peter Zijlstra <peterz@infradead.org> wrote:

> > It looks like what you want is:
> > 
> > 	hrtimer_forward(hrt, period);
> > 
> > unconditionally.

> In the ideal world yes. But my thinking was that timers may not be so
> accurate to deliver interrupts, over the time the timeout error may
> accumulate so that eventually timers will be out of sync.

Timers have a global time base. Even if individual deliveries have an
error, there is no accumulated error.


  reply	other threads:[~2015-11-10 14:58 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-11-10  0:21 [RFC PATCH v2 0/3] CFS idle injection Jacob Pan
2015-11-10  0:21 ` [RFC PATCH v2 1/3] ktime: add a roundup function Jacob Pan
2015-11-10  0:21 ` [RFC PATCH v2 2/3] timer: relax tick stop in idle entry Jacob Pan
2015-11-10  0:21 ` [RFC PATCH v2 3/3] sched: introduce synchronized idle injection Jacob Pan
2015-11-10 13:23   ` Peter Zijlstra
2015-11-10 14:01     ` Jacob Pan
2015-11-10 14:58       ` Peter Zijlstra [this message]
2015-11-10 16:28         ` Jacob Pan
2015-11-10 16:36           ` Peter Zijlstra
2015-11-10 16:50             ` Jacob Pan
2015-11-10 17:00               ` Peter Zijlstra
2015-11-10 17:14                 ` Jacob Pan
2015-11-10 18:41     ` Jacob Pan

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=20151110145823.GD17308@twins.programming.kicks-ass.net \
    --to=peterz@infradead.org \
    --cc=andi.kleen@intel.com \
    --cc=dietmar.eggemann@arm.com \
    --cc=edubezval@gmail.com \
    --cc=jacob.jun.pan@linux.intel.com \
    --cc=len.brown@intel.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=pjt@google.com \
    --cc=punit.agrawal@arm.com \
    --cc=rafael.j.wysocki@intel.com \
    --cc=srinivas.pandruvada@linux.intel.com \
    --cc=tglx@linutronix.de \
    --cc=tim.c.chen@linux.intel.com \
    /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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox