mail archive of the barebox mailing list
 help / color / mirror / Atom feed
From: Sascha Hauer <s.hauer@pengutronix.de>
To: Robert Jarzmik <robert.jarzmik@free.fr>
Cc: barebox@lists.infradead.org
Subject: Re: [PATCH] net: smc1111: fix memory congestions
Date: Mon, 5 Jan 2015 13:11:50 +0100	[thread overview]
Message-ID: <20150105121150.GC4544@pengutronix.de> (raw)
In-Reply-To: <1420142663-6243-2-git-send-email-robert.jarzmik@free.fr>

On Thu, Jan 01, 2015 at 09:04:22PM +0100, Robert Jarzmik wrote:
> As the SMC1111 has a shared pool of 2k memory buckets for both
> transmission and reception, and as there are variants which have as few
> as 4 buckets in total, the memory pool can be hogged by unclaimed
> receptions, and impeed any further transmission.
> 
> This happens on the zylonite pxa board, where 4 packets, most probably
> icmp and arp, fill the 4 buckets, preventing any further ethernet
> transmission, and stalling the driver.
> 
> The fix is rather rough : whenever all the buckets are filled by
> reception packets, and if a transmission is required, the transmission
> code path will empty up all received packets.

I don't know the hardware (not anymore, fortunately ;), but isn't it
possible to dedicate one bucket for transmitting only, so that it will
never be occupied by a received packet?

Sascha

-- 
Pengutronix e.K.                           |                             |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |

_______________________________________________
barebox mailing list
barebox@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/barebox

  reply	other threads:[~2015-01-05 12:12 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-01-01 20:04 [PATCH] commands: loady: fix bug with netconsole Robert Jarzmik
2015-01-01 20:04 ` [PATCH] net: smc1111: fix memory congestions Robert Jarzmik
2015-01-05 12:11   ` Sascha Hauer [this message]
2015-01-05 16:16     ` robert.jarzmik
2015-01-06 13:58       ` Sascha Hauer
2015-01-01 20:04 ` [PATCH] net: smc1111: move print_packet function Robert Jarzmik
2015-01-05 12:12   ` Sascha Hauer
2015-01-05 12:12 ` [PATCH] commands: loady: fix bug with netconsole Sascha Hauer

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=20150105121150.GC4544@pengutronix.de \
    --to=s.hauer@pengutronix.de \
    --cc=barebox@lists.infradead.org \
    --cc=robert.jarzmik@free.fr \
    /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