All of lore.kernel.org
 help / color / mirror / Atom feed
From: Peter Zijlstra <peterz@infradead.org>
To: Luca Abeni <luca.abeni@unitn.it>
Cc: Kirill Tkhai <tkhai@yandex.ru>, Juri Lelli <juri.lelli@arm.com>,
	Ingo Molnar <mingo@redhat.com>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"juri.lelli@gmail.com" <juri.lelli@gmail.com>
Subject: Re: Another SCHED_DEADLINE bug (with bisection and possible fix)
Date: Thu, 15 Jan 2015 13:23:23 +0100	[thread overview]
Message-ID: <20150115122323.GU23965@worktop.programming.kicks-ass.net> (raw)
In-Reply-To: <54B7A33F.20904@unitn.it>

On Thu, Jan 15, 2015 at 12:23:43PM +0100, Luca Abeni wrote:
> There are some parts of the patch that I do not understand (for example:
> if I understand well, if the task is not throttled you set dl_new to 1...
> And if it is throttled you change its current runtime and scheduling deadline...
> Why?)
> Anyway, I tested the patch and I confirm that it fixes the hang I originally
> reported.

I'll go look at the patch in a wee bit. But Juri, Luca, could you
describe the correct behaviour?

>From what I understand we should either modify the tasks run/sleep stats
when we change its parameters or we should schedule a delayed release of
the bandwidth delta (when it reaches its 0-lag point, if thats in the
future).

Doing neither will allow one to game the reservation system afaict.

  reply	other threads:[~2015-01-15 12:23 UTC|newest]

Thread overview: 26+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-12-29 23:27 Another SCHED_DEADLINE bug (with bisection and possible fix) luca abeni
2015-01-04 22:51 ` Kirill Tkhai
2015-01-05 15:21   ` Luca Abeni
2015-01-05 23:07     ` Kirill Tkhai
2015-01-07  7:01       ` Luca Abeni
2015-01-07 12:29         ` Kirill Tkhai
2015-01-07 12:45           ` Luca Abeni
2015-01-07 13:04             ` Kirill Tkhai
2015-01-07 13:14               ` Luca Abeni
2015-01-09 11:15               ` Luca Abeni
2015-01-09 11:46                 ` Kirill Tkhai
2015-01-13  8:10           ` Juri Lelli
2015-01-13  9:26             ` Kirill Tkhai
2015-01-13 14:04               ` Peter Zijlstra
2015-01-14 12:43                 ` Kirill Tkhai
2015-01-15 11:23                   ` Luca Abeni
2015-01-15 12:23                     ` Peter Zijlstra [this message]
2015-01-15 13:35                       ` Luca Abeni
2015-01-28 14:08                         ` Peter Zijlstra
2015-01-28 14:40                           ` Luca Abeni
2015-01-30 10:25                           ` Luca Abeni
2015-01-30 10:35                           ` Juri Lelli
2015-01-31  9:56                             ` Peter Zijlstra
2015-02-02 11:31                               ` Juri Lelli
2015-02-02 13:57                               ` Luca Abeni
2015-02-04 14:34                           ` [tip:sched/core] sched/deadline: Fix deadline parameter modification handling tip-bot for Peter Zijlstra

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=20150115122323.GU23965@worktop.programming.kicks-ass.net \
    --to=peterz@infradead.org \
    --cc=juri.lelli@arm.com \
    --cc=juri.lelli@gmail.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=luca.abeni@unitn.it \
    --cc=mingo@redhat.com \
    --cc=tkhai@yandex.ru \
    /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.