From: Johan Borkhuis <j.borkhuis@dutchspace.nl>
To: Wolfgang Denk <wd@denx.de>
Cc: linuxppc-embedded@ozlabs.org
Subject: Re: Problems enabling NTP on ELDK
Date: Thu, 06 Sep 2007 09:43:13 +0200 [thread overview]
Message-ID: <46DFAF91.3060102@dutchspace.nl> (raw)
In-Reply-To: <20070905184827.26859247AF@gemini.denx.de>
Wolfgang Denk wrote:
> In message <46DE9322.7080901@dutchspace.nl> you wrote:
>
>> I tried enabling NTP on my embedded machine (using ELDK 4.1, ppc_85xx,
>> kernel version 2.6.14 with Xenomai 2.3.2). After I did that I noticed
>> that ksoftirqd/0 suddenly took almost all processor time (> 95%). What
>> is causing this? Is there a way around this, or is this something that
>> does not cause any problems?
>>
>
> You probably have some poroblems in your kernel port - check the RTC
> driver and related modules like I2C etc. Of course this depends on
> the NTP configuration you use, but the only kernel interaction I can
> think of that could cause this is if you interact with the RTC. [I
> guess that normal network traffic is working fine on your board.]
>
All other functions are working fine: no problem with network or other
PCI devices.
I disabled all RTC and I2C devices, and the problem disappeared. After
enabling all items one by one the cause of the problem seems to be the
DS1375 RTC: after I enable this and start NTPD ksoftirqd goes wild
again. I do not see any other special activity: no extra interrupts in
/proc/interrupts, and also no other RTC related errors or messages. Also
OpenPIC does not show any extra interrupts.
Is there a way to find out what interrupt is causing ksoftirqd to be
triggered?
> BTW: ELDK 4.1 comes with a 2.6.19.2 kernel - is there a special
> reason that you use such an obsoletel kernel tree?
>
I am using an MVME3100 board together with Xenomai. This board has
support for version 2.6.14-ppc and 2.6.20-ppc, while Xenomai/Adeos is
supported on 2.6.14 and 2.6.19. I did not yet find time to backport the
support to 2.6.19.
Kind regards,
Johan Borkhuis
prev parent reply other threads:[~2007-09-06 7:43 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-09-05 11:29 Problems enabling NTP on ELDK Johan Borkhuis
2007-09-05 18:48 ` Wolfgang Denk
2007-09-06 7:43 ` Johan Borkhuis [this message]
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=46DFAF91.3060102@dutchspace.nl \
--to=j.borkhuis@dutchspace.nl \
--cc=linuxppc-embedded@ozlabs.org \
--cc=wd@denx.de \
/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.