From: James Bottomley <James.Bottomley@HansenPartnership.com>
To: Tejun Heo <tj@kernel.org>, Jan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@kernel.dk>,
linux-block@vger.kernel.org,
Dan Williams <dan.j.williams@intel.com>,
Omar Sandoval <osandov@osandov.com>,
Arthur Marsh <arthur.marsh@internode.on.net>,
linux-scsi@vger.kernel.org
Subject: Re: [PATCH 1/4] block: Allow bdi re-registration
Date: Wed, 08 Mar 2017 15:17:08 -0800 [thread overview]
Message-ID: <1489015028.24892.17.camel@HansenPartnership.com> (raw)
In-Reply-To: <20170308225542.GB21117@htj.duckdns.org>
On Wed, 2017-03-08 at 17:55 -0500, Tejun Heo wrote:
> Hello,
>
> On Wed, Mar 08, 2017 at 05:48:31PM +0100, Jan Kara wrote:
> > @@ -710,6 +710,11 @@ static void cgwb_bdi_destroy(struct
> > backing_dev_info *bdi)
> > */
> > atomic_dec(&bdi->usage_cnt);
> > wait_event(cgwb_release_wait, !atomic_read(&bdi
> > ->usage_cnt));
> > + /*
> > + * Grab back our reference so that we hold it when @bdi
> > gets
> > + * re-registered.
> > + */
> > + atomic_inc(&bdi->usage_cnt);
>
> So, this is more re-initializing the ref to the initial state so that
> it can be re-used, right? Maybe ATOMIC_INIT() is a better choice
> here just to clarify what's going on?
Seconded. Eventually this is going to get converted to a refcount_t
and it will dump a spurious warning on the 0->1 transition. We can
avoid that by making this a proper initialization.
James
next prev parent reply other threads:[~2017-03-08 23:17 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-03-08 16:48 [PATCH 0/4] block: Fixes for bdi handling Jan Kara
2017-03-08 16:48 ` [PATCH 1/4] block: Allow bdi re-registration Jan Kara
2017-03-08 22:55 ` Tejun Heo
2017-03-08 23:17 ` James Bottomley [this message]
2017-03-09 9:10 ` Jan Kara
2017-03-08 16:48 ` [PATCH 2/4] bdi: Fix use-after-free in wb_congested_put() Jan Kara
2017-03-08 22:56 ` Tejun Heo
2017-03-08 16:48 ` [PATCH 3/4] block: Make del_gendisk() safer for disks without queues Jan Kara
2017-03-08 22:57 ` Tejun Heo
2017-03-08 16:48 ` [PATCH 4/4] Revert "scsi, block: fix duplicate bdi name registration crashes" Jan Kara
2017-03-08 17:12 ` Dan Williams
2017-03-08 16:50 ` [PATCH 0/4] block: Fixes for bdi handling Omar Sandoval
2017-03-08 17:39 ` Omar Sandoval
2017-03-08 16:55 ` Jens Axboe
2017-03-09 9:05 ` Arthur Marsh
-- strict thread matches above, loose matches on Subject: below --
2017-03-09 10:16 [PATCH 0/4 v2] " Jan Kara
2017-03-09 10:16 ` [PATCH 1/4] block: Allow bdi re-registration Jan Kara
2017-03-09 16:39 ` Tejun Heo
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=1489015028.24892.17.camel@HansenPartnership.com \
--to=james.bottomley@hansenpartnership.com \
--cc=arthur.marsh@internode.on.net \
--cc=axboe@kernel.dk \
--cc=dan.j.williams@intel.com \
--cc=jack@suse.cz \
--cc=linux-block@vger.kernel.org \
--cc=linux-scsi@vger.kernel.org \
--cc=osandov@osandov.com \
--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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.