From: Dave Chinner <david@fromorbit.com>
To: SF Markus Elfring <elfring@users.sourceforge.net>
Cc: Julia Lawall <julia.lawall@lip6.fr>,
kernel-janitors@vger.kernel.org,
LKML <linux-kernel@vger.kernel.org>,
xfs@oss.sgi.com
Subject: Re: [PATCH] XFS: Delete unnecessary checks before the function call "xfs_qm_dqrele"
Date: Tue, 30 Jun 2015 07:43:55 +1000 [thread overview]
Message-ID: <20150629214355.GE7943@dastard> (raw)
In-Reply-To: <558D1833.3080009@users.sourceforge.net>
On Fri, Jun 26, 2015 at 11:15:31AM +0200, SF Markus Elfring wrote:
> From: Markus Elfring <elfring@users.sourceforge.net>
> Date: Fri, 26 Jun 2015 11:05:41 +0200
>
> The xfs_qm_dqrele() function tests whether its argument is NULL and
> then returns immediately.
True.
> Thus the test around the call is not needed.
But wrong.
xfs_dqrele_inode() gets called on every inode in the inode cache,
and this change results in a cacheline in every inode being dirtied
even if they don't have dquots attached. Given the inode cache can
hold tens to hundreds of millions of inodes on large machines, we
don't want to dirty any cachelines we don't need to while walking
the inode cache and releasing dquots...
Cheers,
Dave.
--
Dave Chinner
david@fromorbit.com
_______________________________________________
xfs mailing list
xfs@oss.sgi.com
http://oss.sgi.com/mailman/listinfo/xfs
next prev parent reply other threads:[~2015-06-29 21:44 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <5307CAA2.8060406@users.sourceforge.net>
[not found] ` <alpine.DEB.2.02.1402212321410.2043@localhost6.localdomain6>
[not found] ` <530A086E.8010901@users.sourceforge.net>
[not found] ` <alpine.DEB.2.02.1402231635510.1985@localhost6.localdomain6>
[not found] ` <530A72AA.3000601@users.sourceforge.net>
[not found] ` <alpine.DEB.2.02.1402240658210.2090@localhost6.localdomain6>
[not found] ` <530B5FB6.6010207@users.sourceforge.net>
[not found] ` <alpine.DEB.2.10.1402241710370.2074@hadrien>
[not found] ` <530C5E18.1020800@users.sourceforge.net>
[not found] ` <alpine.DEB.2.10.1402251014170.2080@hadrien>
[not found] ` <530CD2C4.4050903@users.sourceforge.net>
[not found] ` <alpine.DEB.2.10.1402251840450.7035@hadrien>
[not found] ` <530CF8FF.8080600@users.sourceforge.net>
[not found] ` <alpine.DEB.2.02.1402252117150.2047@localhost6.localdomain6>
[not found] ` <530DD06F.4090703@users.sourceforge.net>
[not found] ` <alpine.DEB.2.02.1402262129250.2221@localhost6.localdomain6>
[not found] ` <5317A59D.4@users.sourceforge.net>
2014-11-29 16:45 ` [PATCH 1/1] XFS: Deletion of unnecessary checks before two function calls SF Markus Elfring
2014-11-30 23:09 ` Dave Chinner
2015-06-26 9:15 ` [PATCH] XFS: Delete unnecessary checks before the function call "xfs_qm_dqrele" SF Markus Elfring
2015-06-29 21:43 ` Dave Chinner [this message]
2015-07-01 7:50 ` XFS: Fine-tuning for checks before the function call "xfs_qm_dqrele"? SF Markus Elfring
2015-07-02 0:19 ` Dave Chinner
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=20150629214355.GE7943@dastard \
--to=david@fromorbit.com \
--cc=elfring@users.sourceforge.net \
--cc=julia.lawall@lip6.fr \
--cc=kernel-janitors@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=xfs@oss.sgi.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