From: Benjamin LaHaise <bcrl@kvack.org>
To: Andi Kleen <ak@suse.de>
Cc: dipankar@in.ibm.com, Andrew Morton <akpm@linux-foundation.org>,
linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org
Subject: Re: [PATCH/RFC] synchronize_rcu(): high latency on idle system
Date: Sat, 12 Jan 2008 12:51:35 -0500 [thread overview]
Message-ID: <20080112175135.GK28570@kvack.org> (raw)
In-Reply-To: <20080112023759.GG21068@bingen.suse.de>
On Sat, Jan 12, 2008 at 03:37:59AM +0100, Andi Kleen wrote:
> > And yes, the
> > network stack shouldn't call synchronize_rcu() quite so much, but fixing that
> > is a little more involved.
>
> ... but the correct solution.
There has to be at least 1 synchronize_rcu() or equivalent in the
unregister_netdev() path. I suspect the easiest way to fix it might be to
use call_rcu() to actually free the network device, as anything else will
limit performance of single threaded teardown (ie, when an l2tp daemon
gets terminated via kill -9). This means an API change that exposes
rcu for unregister_netdev().
-ben
--
"Time is of no importance, Mr. President, only life is important."
Don't Email: <zyntrop@kvack.org>.
next prev parent reply other threads:[~2008-01-12 17:51 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-01-12 1:26 [PATCH/RFC] synchronize_rcu(): high latency on idle system Benjamin LaHaise
2008-01-12 2:37 ` Andi Kleen
2008-01-12 17:51 ` Benjamin LaHaise [this message]
2008-01-12 18:35 ` Andi Kleen
2008-01-13 1:52 ` Stephen Hemminger
2008-01-13 15:34 ` Andi Kleen
2008-01-14 17:19 ` Stephen Hemminger
2008-01-12 9:23 ` Peter Zijlstra
2008-01-12 16:55 ` Paul E. McKenney
2008-01-12 17:33 ` Andi Kleen
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=20080112175135.GK28570@kvack.org \
--to=bcrl@kvack.org \
--cc=ak@suse.de \
--cc=akpm@linux-foundation.org \
--cc=dipankar@in.ibm.com \
--cc=linux-arch@vger.kernel.org \
--cc=linux-kernel@vger.kernel.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 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.