mail archive of the barebox mailing list
 help / color / mirror / Atom feed
From: Sascha Hauer <s.hauer@pengutronix.de>
To: barebox@lists.infradead.org
Subject: Re: [PATCH 4/4] net: phy: Use poller for periodic link check
Date: Wed, 24 Sep 2014 07:09:29 +0200	[thread overview]
Message-ID: <20140924050929.GF4958@pengutronix.de> (raw)
In-Reply-To: <1411024275-31766-5-git-send-email-s.hauer@pengutronix.de>

On Thu, Sep 18, 2014 at 09:11:15AM +0200, Sascha Hauer wrote:
> This continuously updates the link status in the background. The networking
> code no longer has to periodically update the link status itself but instead
> can only check for phydev->link.
> With this we also always have link status changes printed to the console.

Nice try, but this doesn't work, so I'll drop this one.

The problem comes with USB network adapters (SPI would be the same).
pollers get called in is_timeout() loops like USB host drivers use
to poll for urb completion. So when network transfers happen and
the network driver issues USB requests it can happen that in the
USB host driver a poller triggers which with the periodic link check
now triggers a USB request itself. barebox can't (and shouldn't) handle
this reentrancy.

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:[~2014-09-24  5:09 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-09-18  7:11 net: phy updates Sascha Hauer
2014-09-18  7:11 ` [PATCH 1/4] net: phy: introduce phy_aneg_done Sascha Hauer
2014-09-18  7:11 ` [PATCH 2/4] net: phy: Use xzalloc for small allocations Sascha Hauer
2014-09-18  7:11 ` [PATCH 3/4] net: phy: don't use 'dev' as name for variables of type struct phy_device Sascha Hauer
2014-09-18  7:11 ` [PATCH 4/4] net: phy: Use poller for periodic link check Sascha Hauer
2014-09-24  5:09   ` Sascha Hauer [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=20140924050929.GF4958@pengutronix.de \
    --to=s.hauer@pengutronix.de \
    --cc=barebox@lists.infradead.org \
    /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