From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Rakib Mullick <rakib.mullick@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>, LKML <linux-kernel@vger.kernel.org>
Subject: Re: [Question] sched: Should nr_uninterruptible be decremented in ttwu_do_activate()?
Date: Wed, 11 Jan 2012 18:29:15 +0100 [thread overview]
Message-ID: <1326302955.2442.174.camel@twins> (raw)
In-Reply-To: <CADZ9YHicin2YjGm_m9B0LMv3NW1Z3cb7HSCaqwycFmVfRpvpWA@mail.gmail.com>
On Wed, 2012-01-11 at 23:22 +0600, Rakib Mullick wrote:
> Hello all,
>
> In ttwu_do_activate(), we're decrementing nr_uninterruptible if
> p->sched_contributes_to_load (for SMP=y). But, we're also decrementing
> nr_uninterruptible from activate_task at the same path. Why we're
> doing it twice for a single task activation path?
activate_task() does:
if (task_contributes_to_load(p))
rq->nr_uninterruptible--;
Now task_contributes_to_load() reads like:
#define task_contributes_to_load(task) \
((task->state & TASK_UNINTERRUPTIBLE) != 0 && \
(task->flags & PF_FREEZING) == 0)
which will be false, since we've set TASK_WAKING.
next prev parent reply other threads:[~2012-01-11 17:29 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-01-11 17:22 [Question] sched: Should nr_uninterruptible be decremented in ttwu_do_activate()? Rakib Mullick
2012-01-11 17:29 ` Peter Zijlstra [this message]
2012-01-12 6:09 ` Rakib Mullick
2012-01-12 7:25 ` Peter Zijlstra
2012-01-12 17:08 ` Rakib Mullick
2012-01-12 20:25 ` Peter Zijlstra
2012-01-16 7:53 ` Michael Wang
2012-01-16 8:27 ` Rakib Mullick
2012-01-16 9:22 ` Michael Wang
2012-01-16 17:22 ` Rakib Mullick
2012-01-16 13:00 ` Hillf Danton
2012-01-16 17:26 ` Rakib Mullick
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=1326302955.2442.174.camel@twins \
--to=a.p.zijlstra@chello.nl \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@elte.hu \
--cc=rakib.mullick@gmail.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