All of lore.kernel.org
 help / color / mirror / Atom feed
From: Wolfgang Grandegger <wg@grandegger.com>
To: Wolfram Sang <w.sang@pengutronix.de>
Cc: linuxppc-dev <Linuxppc-dev@ozlabs.org>
Subject: Re: Bestcomm trouble with NAPI for MPC5200 FEC
Date: Fri, 10 Jul 2009 10:26:57 +0200	[thread overview]
Message-ID: <4A56FB51.3050009@grandegger.com> (raw)
In-Reply-To: <20090710080830.GA3241@pengutronix.de>

Wolfram Sang wrote:
> Hello Wolfgang,
> 
>> I'm currently trying to implement NAPI for the FEC on the MPC5200 to
>> solve the well known problem, that network packet storms can cause
>> interrupt flooding, which may totally block the system. The NAPI

Just bombard the FEC with network packets. I use pktgen on the host and
I could send you a script if you like.

> That's great news. Do you happen to have a scenario which reliably triggers the
> problem? Then I could do some testing as well. I haven't seen this on our
> boards for quite a while, but I'd like to verify.
> 
>> - With 2.6.31-rc2, the RFIFO error occurs quickly which does reset the
>>   FEC and Bestcomm (unfortunately, this does trigger an oops because
>>   it's called from the interrupt context, but that's another issue).
> 
> +1 for "error handling resets too much"

Yes, and furthermore it's leaking skb's :-(.

Wolfgang.

      reply	other threads:[~2009-07-10  8:27 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-07-09 20:33 Bestcomm trouble with NAPI for MPC5200 FEC Wolfgang Grandegger
2009-07-09 21:22 ` Grant Likely
2009-07-10  7:37   ` Wolfgang Grandegger
2009-07-10  9:16   ` Wolfgang Grandegger
2009-07-10  8:08 ` Wolfram Sang
2009-07-10  8:26   ` Wolfgang Grandegger [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=4A56FB51.3050009@grandegger.com \
    --to=wg@grandegger.com \
    --cc=Linuxppc-dev@ozlabs.org \
    --cc=w.sang@pengutronix.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.