All of lore.kernel.org
 help / color / mirror / Atom feed
From: caiyuqing <yuqingcaik@gmail.com>
To: Richard Cochran <richardcochran@gmail.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: question about context switch on arm Linux
Date: Sun, 21 Oct 2012 16:19:50 +0800	[thread overview]
Message-ID: <5083B026.1030307@gmail.com> (raw)
In-Reply-To: <20121021074434.GB4735@netboy.at.omicron.at>

于 2012年10月21日 15:44, Richard Cochran 写道:
> On Sun, Oct 21, 2012 at 02:02:42PM +0800, caiyuqing wrote:
>> hi, all.
>> I have some questions about context switch on arm Linux (my target is
>> ARMv7-a).
>> 1. Does arm linux support FCSE to handle the context switch?
> No, mainline Linux does not support FCSE. However, you can use Gilles'
> unoffical (but working) FCSE branches at
>
>    http://git.xenomai.org/?p=ipipe-gch.git;a=summary
>
>> 2. If using FCSE, that means the processes number limit is 128 and the
>> memory limit is 32MB per process, is that right?
> Yes and no.
>
> Gilles' patches offer a "strict mode" and a "best effort" mode. The
> strict mode does have the limitation, but the best effort mode does
> not.
>
> HTH,
> Richard
Richard, thanks for your reply.
mainline Linux doesn't support FCSE, if so, when kernel switch a process 
to another(these two process share the same virtual memory space), that 
means the vitrual-to-physical address should be remaped, TLB shuold be 
invalid, CACHE should be flushed, right?

qing






  reply	other threads:[~2012-10-21  8:19 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-10-21  6:02 question about context switch on arm Linux caiyuqing
2012-10-21  7:44 ` Richard Cochran
2012-10-21  8:19   ` caiyuqing [this message]
2012-10-21 12:00     ` Richard Cochran

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=5083B026.1030307@gmail.com \
    --to=yuqingcaik@gmail.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=richardcochran@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 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.