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$(echo .)nl \
--cc=linuxppc-embedded@ozlabs$(echo .)org \
--cc=wd@denx$(echo .)de \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
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