linux-rt-users.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Kirill Tkhai <tkhai@yandex.ru>
To: Honghui Zhang <zhanghonghui@huawei.com>
Cc: Steven Rostedt <rostedt@goodmis.org>,
	linux-kernel@vger.kernel.org, Ingo Molnar <mingo@kernel.org>,
	Peter Zijlstra <peterz@infradead.org>,
	linux-rt-users <linux-rt-users@vger.kernel.org>
Subject: Re:[PATCH] sched/rt: Decrease number of calls of push_rt_task() in push_rt_tasks()
Date: Tue, 05 Feb 2013 14:27:04 +0400	[thread overview]
Message-ID: <798741360060024@web12h.yandex.ru> (raw)



> On 2013/2/5 15:22, Kirill Tkhai wrote:
> 
>>> Suppose we have a large number of cpus(say 4096), with the last one running
>>> a low-priority task on it. Is it possible with this patch we will never reach
>>> the last cpu in case that previous cpu has complete the pulled task?
>>
>> Yes. But this patch is about several pushable tasks on the same cpu.
>>
>> Kirill
> 
> Maybe I haven't make myself understood, but in that case, there will be a higher-priority
> task in the runqueue of the pushing cpu, and a lower-priority task running in the last cpu
> which could not be preempt by push_rt_task(), I don't think it's acceptable.

Sure, I tried to prevent the fact of call of this function with locks of spinlocks etc. It may
be useful on system like 2 CPU, but it's not necessary for large systems. I'm not persist in this.

Kirill

> 
> Hans
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html


 -- 

             reply	other threads:[~2013-02-05 10:27 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-02-05 10:27 Kirill Tkhai [this message]
  -- strict thread matches above, loose matches on Subject: below --
2013-02-05  7:22 Re:[PATCH] sched/rt: Decrease number of calls of push_rt_task() in push_rt_tasks() Kirill Tkhai

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=798741360060024@web12h.yandex.ru \
    --to=tkhai@yandex.ru \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-rt-users@vger.kernel.org \
    --cc=mingo@kernel.org \
    --cc=peterz@infradead.org \
    --cc=rostedt@goodmis.org \
    --cc=zhanghonghui@huawei.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;
as well as URLs for NNTP newsgroup(s).