From: NeilBrown <neilb@suse.de>
To: Shaohua Li <shli@kernel.org>
Cc: linux-raid@vger.kernel.org, djbw@fb.com
Subject: Re: [patch 3/3] raid5: relieve lock contention in get_active_stripe()
Date: Wed, 28 Aug 2013 14:32:52 +1000 [thread overview]
Message-ID: <20130828143252.1d48b04b@notabene.brown> (raw)
In-Reply-To: <20130827085330.GA30133@kernel.org>
[-- Attachment #1: Type: text/plain, Size: 760 bytes --]
On Tue, 27 Aug 2013 16:53:30 +0800 Shaohua Li <shli@kernel.org> wrote:
> On Tue, Aug 27, 2013 at 01:17:52PM +1000, NeilBrown wrote:
>
> > Then get_active_stripe wouldn't need to worry about device_lock at all and
> > would only need to get the hash lock for the particular sector. That should
> > make it a lot simpler.
>
> did you mean get_active_stripe() doesn't need device_lock for any code path?
> How could it be safe? device_lock still protects something like handle_list,
> delayed_list, which release_stripe() will use while a get_active_stripe can run
> concurrently.
Yes you will still need device_lock to protect list_del_init(&sh->lru),
as well as the hash lock.
Do you need device_lock anywhere else in there?
NeilBrown
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 828 bytes --]
next prev parent reply other threads:[~2013-08-28 4:32 UTC|newest]
Thread overview: 26+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-08-12 2:24 [patch 0/3] raid5: relieve lock contention of get_active_stripe() Shaohua Li
2013-08-12 2:24 ` [patch 1/3] raid5: rename stripe_hash() Shaohua Li
2013-08-12 2:24 ` [patch 2/3] wait: add wait_event_cmd() Shaohua Li
2013-08-12 2:24 ` [patch 3/3] raid5: relieve lock contention in get_active_stripe() Shaohua Li
2013-08-27 3:17 ` NeilBrown
2013-08-27 8:53 ` Shaohua Li
2013-08-28 4:32 ` NeilBrown [this message]
2013-08-28 6:39 ` Shaohua Li
2013-09-03 6:08 ` NeilBrown
2013-09-03 7:02 ` Shaohua Li
2013-09-04 6:41 ` NeilBrown
2013-09-05 5:40 ` Shaohua Li
2013-09-05 6:29 ` NeilBrown
2013-09-05 9:18 ` Shaohua Li
2013-09-09 4:33 ` Shaohua Li
2013-09-10 1:13 ` NeilBrown
2013-09-10 2:35 ` Shaohua Li
2013-09-10 4:06 ` NeilBrown
2013-09-10 4:24 ` Shaohua Li
2013-09-10 5:20 ` NeilBrown
2013-09-10 6:59 ` Shaohua Li
2013-09-10 7:28 ` NeilBrown
2013-09-10 7:37 ` Shaohua Li
2013-09-11 1:34 ` NeilBrown
2013-09-12 1:55 ` Shaohua Li
2013-09-12 5:38 ` NeilBrown
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=20130828143252.1d48b04b@notabene.brown \
--to=neilb@suse.de \
--cc=djbw@fb.com \
--cc=linux-raid@vger.kernel.org \
--cc=shli@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;
as well as URLs for NNTP newsgroup(s).