From: Richard Cochran <richardcochran@gmail.com>
To: "Koehrer Mathias (ETAS/ESW5)" <mathias.koehrer@etas.com>
Cc: Julia Cartwright <julia@ni.com>,
"Williams, Mitch A" <mitch.a.williams@intel.com>,
"Kirsher, Jeffrey T" <jeffrey.t.kirsher@intel.com>,
"linux-rt-users@vger.kernel.org" <linux-rt-users@vger.kernel.org>,
Sebastian Andrzej Siewior <sebastian.siewior@linutronix.de>,
"netdev@vger.kernel.org" <netdev@vger.kernel.org>,
"intel-wired-lan@lists.osuosl.org"
<intel-wired-lan@lists.osuosl.org>, Greg <gvrose8192@gmail.com>
Subject: Re: Kernel 4.6.7-rt13: Intel Ethernet driver igb causes huge latencies in cyclictest
Date: Sat, 15 Oct 2016 00:06:33 +0200 [thread overview]
Message-ID: <20161014220633.GA1811@netboy> (raw)
In-Reply-To: <f395ea6cd1274fac83d2744121da7441@FE-MBX1012.de.bosch.com>
On Fri, Oct 14, 2016 at 08:58:22AM +0000, Koehrer Mathias (ETAS/ESW5) wrote:
> @@ -753,7 +756,9 @@ u32 igb_rd32(struct e1000_hw *hw, u32 re
> if (E1000_REMOVED(hw_addr))
> return ~value;
>
> + trace_igb(801);
> value = readl(&hw_addr[reg]);
> + trace_igb(802);
Nothing prevents this code from being preempted between the two trace
points, and so you can't be sure whether the time delta in the trace
is caused by the PCIe read stalling or not.
Thanks,
Richard
next prev parent reply other threads:[~2016-10-14 22:06 UTC|newest]
Thread overview: 34+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-09-22 12:44 Kernel 4.6.7-rt13: Intel Ethernet driver igb causes huge latencies in cyclictest Koehrer Mathias (ETAS/ESW5)
2016-09-22 15:12 ` Sebastian Andrzej Siewior
2016-09-23 6:38 ` AW: " Koehrer Mathias (ETAS/ESW5)
2016-09-23 11:40 ` Koehrer Mathias (ETAS/ESW5)
2016-09-23 12:32 ` Sebastian Andrzej Siewior
2016-09-23 13:23 ` Koehrer Mathias (ETAS/ESW5)
2016-09-23 14:41 ` Sebastian Andrzej Siewior
2016-09-26 11:12 ` Koehrer Mathias (ETAS/ESW5)
2016-09-28 19:45 ` Julia Cartwright
2016-10-04 14:33 ` Koehrer Mathias (ETAS/ESW5)
2016-10-04 19:34 ` Julia Cartwright
2016-10-05 7:02 ` Koehrer Mathias (ETAS/ESW5)
2016-10-05 15:59 ` Julia Cartwright
2016-10-06 7:01 ` Koehrer Mathias (ETAS/ESW5)
2016-10-06 10:12 ` Henri Roosen
2016-10-06 17:58 ` Williams, Mitch A
2016-10-07 8:58 ` Koehrer Mathias (ETAS/ESW5)
2016-10-10 19:39 ` Julia Cartwright
2016-10-13 6:15 ` Koehrer Mathias (ETAS/ESW5)
2016-10-13 10:57 ` Koehrer Mathias (ETAS/ESW5)
2016-10-13 14:02 ` David Laight
2016-10-13 16:18 ` Julia Cartwright
2016-10-14 8:58 ` Koehrer Mathias (ETAS/ESW5)
2016-10-14 19:55 ` Julia Cartwright
2016-10-17 15:00 ` Koehrer Mathias (ETAS/ESW5)
2016-10-17 15:39 ` [Intel-wired-lan] " Alexander Duyck
2016-10-17 18:32 ` Julia Cartwright
2016-10-18 8:43 ` Koehrer Mathias (ETAS/ESW5)
2016-10-14 22:06 ` Richard Cochran [this message]
2016-10-17 18:36 ` Julia Cartwright
2016-10-17 19:03 ` Richard Cochran
2016-09-26 11:48 ` Alexander Stein
2016-09-27 6:29 ` Koehrer Mathias (ETAS/ESW5)
2016-09-27 7:56 ` Mathias Koehrer
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=20161014220633.GA1811@netboy \
--to=richardcochran@gmail.com \
--cc=gvrose8192@gmail.com \
--cc=intel-wired-lan@lists.osuosl.org \
--cc=jeffrey.t.kirsher@intel.com \
--cc=julia@ni.com \
--cc=linux-rt-users@vger.kernel.org \
--cc=mathias.koehrer@etas.com \
--cc=mitch.a.williams@intel.com \
--cc=netdev@vger.kernel.org \
--cc=sebastian.siewior@linutronix.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).