From: Greg KH <greg@kroah.com>
To: Jerome Marchand <jmarchan@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>, Jens Axboe <jaxboe@fusionio.com>,
Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>,
Linus Torvalds <torvalds@linux-foundation.org>,
Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 2/2] block: fix accounting bug on cross partition merges
Date: Tue, 4 Jan 2011 13:00:11 -0800 [thread overview]
Message-ID: <20110104210011.GB4180@kroah.com> (raw)
In-Reply-To: <4D2342E1.8010405@redhat.com>
On Tue, Jan 04, 2011 at 04:55:13PM +0100, Jerome Marchand wrote:
> Also add a refcount to struct hd_struct to keep the partition in
> memory as long as users exist. We use kref_test_and_get() to ensure
> we don't add a reference to a partition which is going away.
No, don't do this, use a kref correctly and no such function should be
needed.
> + } else {
> + part = disk_map_sector_rcu(rq->rq_disk, blk_rq_pos(rq));
That is the function that should properly increment the reference count
on the object. If the object is "being removed", then it will return
NULL and you need to check that. Do that and you do not need to add:
> + if (!kref_test_and_get(&part->ref)) {
At all.
thanks,
greg k-h
next prev parent reply other threads:[~2011-01-04 21:00 UTC|newest]
Thread overview: 47+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-12-06 9:44 [PATCH 1/2] Don't merge different partition's IOs Yasuaki Ishimatsu
2010-12-06 16:08 ` Linus Torvalds
2010-12-07 7:18 ` Satoru Takeuchi
2010-12-07 18:39 ` Vivek Goyal
2010-12-08 7:33 ` Jens Axboe
2010-12-08 7:59 ` Satoru Takeuchi
2010-12-08 8:06 ` Jens Axboe
2010-12-08 8:11 ` Satoru Takeuchi
2010-12-08 14:46 ` Jens Axboe
2010-12-08 15:51 ` Vivek Goyal
2010-12-08 15:58 ` Vivek Goyal
2010-12-10 11:22 ` Jerome Marchand
2010-12-10 16:12 ` Jerome Marchand
2010-12-10 16:55 ` Vivek Goyal
2010-12-14 20:25 ` Jens Axboe
2010-12-17 13:42 ` [PATCH] block: fix accounting bug on cross partition merges Jerome Marchand
2010-12-17 19:06 ` Jens Axboe
2010-12-17 22:32 ` Vivek Goyal
2010-12-23 15:10 ` Jerome Marchand
2010-12-23 15:39 ` Vivek Goyal
2010-12-23 17:04 ` Jerome Marchand
2010-12-24 19:29 ` Vivek Goyal
2011-01-04 15:52 ` [PATCH 1/2] kref: add kref_test_and_get Jerome Marchand
2011-01-04 15:55 ` [PATCH 2/2] block: fix accounting bug on cross partition merges Jerome Marchand
2011-01-04 21:00 ` Greg KH [this message]
2011-01-05 13:51 ` Jerome Marchand
2011-01-05 16:00 ` Greg KH
2011-01-05 16:19 ` Jerome Marchand
2011-01-05 16:27 ` Greg KH
2011-01-05 13:55 ` Jens Axboe
2011-01-05 15:58 ` Greg KH
2011-01-05 18:46 ` Jens Axboe
2011-01-05 20:08 ` Greg KH
2011-01-05 21:38 ` Jens Axboe
2011-01-05 22:16 ` Greg KH
2011-01-06 9:46 ` Jens Axboe
2011-01-05 14:00 ` Jens Axboe
2011-01-05 14:09 ` Jerome Marchand
2011-01-05 14:17 ` Jens Axboe
2011-01-04 16:05 ` [PATCH 1/2] kref: add kref_test_and_get Eric Dumazet
2011-01-05 15:02 ` [PATCH 1/2 v2] " Jerome Marchand
2011-01-05 15:43 ` Alexey Dobriyan
2011-01-05 15:57 ` Greg KH
2011-01-05 15:56 ` Greg KH
2011-01-04 20:57 ` [PATCH 1/2] " Greg KH
2011-01-05 13:35 ` Jerome Marchand
2011-01-05 15:55 ` Greg KH
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=20110104210011.GB4180@kroah.com \
--to=greg@kroah.com \
--cc=isimatu.yasuaki@jp.fujitsu.com \
--cc=jaxboe@fusionio.com \
--cc=jmarchan@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=takeuchi_satoru@jp.fujitsu.com \
--cc=torvalds@linux-foundation.org \
--cc=vgoyal@redhat.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
all inboxes | Powered by JetHome®