From: Al Viro <viro@zeniv.linux.org.uk>
To: Jeff Layton <jlayton@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
Ilya Dryomov <idryomov@gmail.com>,
ceph-devel@vger.kernel.org,
Linux List Kernel Mailing <linux-kernel@vger.kernel.org>
Subject: Re: [GIT PULL] Ceph fixes for 5.1-rc7
Date: Sun, 28 Apr 2019 05:38:12 +0100 [thread overview]
Message-ID: <20190428043801.GE2217@ZenIV.linux.org.uk> (raw)
In-Reply-To: <b175faae4bb98d3379a8642fe5f4e00587c3a734.camel@kernel.org>
On Fri, Apr 26, 2019 at 01:30:53PM -0400, Jeff Layton wrote:
> > I _probably_ would take allocation out of the loop (e.g. make it
> > __getname(), called unconditionally) and turned it into the
> > d_path.c-style read_seqbegin_or_lock()/need_seqretry()/done_seqretry()
> > loop, so that the first pass would go under rcu_read_lock(), while
> > the second (if needed) would just hold rename_lock exclusive (without
> > bumping the refcount). But that's a matter of (theoretical) livelock
> > avoidance, not the locking correctness for ->d_name accesses.
> >
>
> Yeah, that does sound better. I want to think about this code a bit
FWIW, is there any reason to insist that the pathname is put into the
beginning of the buffer? I mean, instead of path + pathlen we might
return path + offset, with the pathname going from path + offset to
path + PATH_MAX - 1 inclusive, with path being the thing eventually
freed.
It's easier to build the string backwards, seeing that we are walking
from leaf to root...
next prev parent reply other threads:[~2019-04-28 4:38 UTC|newest]
Thread overview: 26+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-04-25 17:47 [GIT PULL] Ceph fixes for 5.1-rc7 Ilya Dryomov
2019-04-25 18:02 ` Linus Torvalds
2019-04-25 18:21 ` Al Viro
2019-04-25 18:24 ` Linus Torvalds
2019-04-25 18:31 ` Al Viro
2019-04-25 18:36 ` Jeff Layton
2019-04-25 18:23 ` Jeff Layton
2019-04-25 20:09 ` Al Viro
2019-04-26 16:25 ` Jeff Layton
2019-04-26 16:36 ` Linus Torvalds
2019-04-26 16:43 ` Linus Torvalds
2019-04-26 17:01 ` Al Viro
2019-04-26 17:08 ` Linus Torvalds
2019-04-26 17:11 ` Al Viro
2019-04-26 20:49 ` Jeff Layton
2019-04-26 21:28 ` Al Viro
2019-04-26 16:50 ` Al Viro
2019-04-26 17:30 ` Jeff Layton
2019-04-28 4:38 ` Al Viro [this message]
2019-04-28 13:27 ` Jeff Layton
2019-04-28 14:48 ` Al Viro
2019-04-28 15:47 ` Jeff Layton
2019-04-28 15:52 ` Al Viro
2019-04-28 16:18 ` Jeff Layton
2019-04-28 16:40 ` Al Viro
2019-04-25 18:35 ` pr-tracker-bot
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=20190428043801.GE2217@ZenIV.linux.org.uk \
--to=viro@zeniv.linux.org.uk \
--cc=ceph-devel@vger.kernel.org \
--cc=idryomov@gmail.com \
--cc=jlayton@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--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;
as well as URLs for NNTP newsgroup(s).