public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Al Viro <viro@ZenIV.linux.org.uk>
To: George Spelvin <linux@horizon.com>
Cc: torvalds@linux-foundation.org, aswin@hp.com, john@stoffel.org,
	linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
	scott.norton@hp.com, Waiman.Long@hp.com
Subject: Re: [PATCH v4 1/1] dcache: Translating dentry into pathname without taking rename_lock
Date: Tue, 10 Sep 2013 01:57:54 +0100	[thread overview]
Message-ID: <20130910005754.GV13318@ZenIV.linux.org.uk> (raw)
In-Reply-To: <20130910004020.29299.qmail@science.horizon.com>

On Mon, Sep 09, 2013 at 08:40:20PM -0400, George Spelvin wrote:
> I'm really wondering about only trying once before taking the write lock.
> Yes, using the lsbit is a cute hack, but are we using it for its cuteness
> rather than its effectiveness?
> 
> Renames happen occasionally.  If that causes all the current pathname
> translations to fall back to the write lock, that is fairly heavy.
> Worse, all of those translations will (unnecessarily) bump the write
> seqcount, triggering *other* translations to fail back to the write-lock
> path.

_What_ "pathname translations"?  Pathname resolution doesn't fall back to
seq_writelock() at all.

  reply	other threads:[~2013-09-10  0:58 UTC|newest]

Thread overview: 25+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-09-09 16:18 [PATCH v4 0/1] dcache: Translating dentry into pathname without taking rename_lock Waiman Long
2013-09-09 16:18 ` [PATCH v4 1/1] " Waiman Long
2013-09-09 17:29   ` Al Viro
2013-09-09 17:45     ` Linus Torvalds
2013-09-09 17:56       ` Waiman Long
2013-09-09 18:06       ` Al Viro
2013-09-09 18:15         ` Linus Torvalds
2013-09-09 18:21         ` Al Viro
2013-09-09 18:36           ` Al Viro
2013-09-09 18:46             ` Al Viro
2013-09-09 18:46             ` Waiman Long
2013-09-09 19:10               ` Al Viro
2013-09-09 19:28                 ` Al Viro
2013-09-09 22:57                   ` Waiman Long
2013-09-10  0:40           ` George Spelvin
2013-09-10  0:57             ` Al Viro [this message]
2013-09-10  1:15               ` Ramkumar Ramachandra
2013-09-10  1:34                 ` Linus Torvalds
2013-09-10  2:25                   ` Al Viro
2013-09-10  2:33                     ` Linus Torvalds
2013-09-10  3:12                   ` Ramkumar Ramachandra
2013-09-10  8:24               ` George Spelvin
2013-09-10  3:57             ` Waiman Long
2013-09-09 17:55     ` Waiman Long
2013-09-09 18:07       ` Al Viro

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=20130910005754.GV13318@ZenIV.linux.org.uk \
    --to=viro@zeniv.linux.org.uk \
    --cc=Waiman.Long@hp.com \
    --cc=aswin@hp.com \
    --cc=john@stoffel.org \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux@horizon.com \
    --cc=scott.norton@hp.com \
    --cc=torvalds@linux-foundation.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