public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Cornelia Huck <cornelia.huck@de.ibm.com>
To: Tejun Heo <tj@kernel.org>
Cc: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Jens Axboe <jens.axboe@oracle.com>, Greg K-H <greg@kroah.com>
Subject: Re: [PATCH] block: fix block_class iteration locking
Date: Mon, 21 Jul 2008 19:34:26 +0200	[thread overview]
Message-ID: <20080721193426.28ad925c@gondolin> (raw)
In-Reply-To: <487B3DA1.7010906@kernel.org>

On Mon, 14 Jul 2008 20:50:57 +0900,
Tejun Heo <tj@kernel.org> wrote:

> > With your patch, you protect against adding/removing devices to/from
> > the class between _start and _stop. This wasn't done previously, and
> > won't be done with Greg's patches (which leaves in the
> > locking/unlocking of block_class_lock). Not sure if I'm missing
> > something here...
> 
> That's mostly the point of this patch.  It wasn't protected properly
> before.  It would be best if there's a safe iterator (maybe use klist?).

Hm, I don't see how a klist would help here since it still allows to
add/remove devices during walking the file.

What we need is more like a "lock/unlock the device list" operation and
a lockless iterator - that would give the same semantics as your patch.

      reply	other threads:[~2008-07-21 17:55 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-07-14  6:06 [PATCH] block: fix block_class iteration locking Tejun Heo
2008-07-14 11:42 ` Cornelia Huck
2008-07-14 11:50   ` Tejun Heo
2008-07-21 17:34     ` Cornelia Huck [this message]

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=20080721193426.28ad925c@gondolin \
    --to=cornelia.huck@de.ibm.com \
    --cc=greg@kroah.com \
    --cc=jens.axboe@oracle.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=tj@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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox