mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Teresa Remmet <t.remmet@phytec.de>
To: David Laight <David.Laight@ACULAB.COM>
Cc: Igor Plyatov <plyatov@gmail.com>,
	"David S. Miller" <davem@davemloft.net>,
	Florian Fainelli <f.fainelli@gmail.com>,
	"netdev@vger.kernel.org" <netdev@vger.kernel.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: phy: SMSC LAN8710/LAN8720 high load
Date: Fri, 15 Jan 2016 10:18:50 +0100	[thread overview]
Message-ID: <1452849530.3483.30.camel@lws-tremmet.phytec.de> (raw)
In-Reply-To: <063D6719AE5E284EB5DD2968C1650D6D1CCC42AE@AcuExch.aculab.com>

Hello David,

Am Dienstag, den 12.01.2016, 11:33 +0000 schrieb David Laight:
> From: Teresa Remmet
> > Sent: 11 January 2016 07:42
> > we have noticed load issues on our AM335x boards with a LAN8710 phy while
> > cpu is idling using 4.4-rc8.
> > 
> > CPU:   0% usr   0% sys   0% nic  99% idle   0% io   0% irq   0% sirq
> > Load average: 1.21 1.16 1.00 1/84 372
> 
> The 'Load average' value is mostly meaningless.
> It includes any process/thread that is sleeping uninterruptably - even
> if the process is never woken (or is only woken for short periods).
> 
> If you have a kernel thread that you don't want affected by signals
> (exits on some request to the driver) then you end up increasing the
> 'load average'.

thank you for your explanation. But I'm still worried that waiting so
long in this function might be a problem.

When I look at the function duration of lan87xx_read_status it takes in
average about 1277869 us. When disabling the the power detect mode the
time drops down to 555.326 us.

As disabling over device tree does not work correct for lan87xx a patch
follows.

Teresa

> 
> 	David
> 

      reply	other threads:[~2016-01-15  9:20 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-01-11  7:41 net: " Teresa Remmet
2016-01-11  8:09 ` Igor Plyatov
2016-01-12 11:33 ` David Laight
2016-01-15  9:18   ` Teresa Remmet [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=1452849530.3483.30.camel@lws-tremmet.phytec.de \
    --to=t.remmet@phytec.de \
    --cc=David.Laight@ACULAB.COM \
    --cc=davem@davemloft.net \
    --cc=f.fainelli@gmail.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=netdev@vger.kernel.org \
    --cc=plyatov@gmail.com \
    /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

all inboxes | Powered by JetHome®