From: Jens Axboe <[email protected]>
To: [email protected]
Cc: [email protected]
Subject: Re: [PATCH 3/3] io-wq: ensure free/busy list browsing see all items
Date: Wed, 13 Nov 2019 19:51:21 -0700 [thread overview]
Message-ID: <[email protected]> (raw)
In-Reply-To: <20191113234251.GH2865@paulmck-ThinkPad-P72>
On 11/13/19 4:42 PM, Paul E. McKenney wrote:
> On Wed, Nov 13, 2019 at 02:32:06PM -0700, Jens Axboe wrote:
>> We have two lists for workers in io-wq, a busy and a free list. For
>> certain operations we want to browse all workers, and we currently do
>> that by browsing the two separate lists. But since these lists are RCU
>> protected, we can potentially miss workers if they move between the two
>> lists while we're browsing them.
>>
>> Add a third list, all_list, that simply holds all workers. A worker is
>> added to that list when it starts, and removed when it exits. This makes
>> the worker iteration cleaner, too.
>>
>> Reported-by: Paul E. McKenney <[email protected]>
>> Signed-off-by: Jens Axboe <[email protected]>
>
> H/T to Olof for asking the question, by the way!
>
> Reviewed-by: Paul E. McKenney <[email protected]>
Thanks! And yes, hat tip to Olof for sure.
--
Jens Axboe
prev parent reply other threads:[~2019-11-14 2:51 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-11-13 21:32 [PATCHSET v2] Improve io_uring cancellations Jens Axboe
2019-11-13 21:32 ` [PATCH 1/3] io_wq: add get/put_work handlers to io_wq_create() Jens Axboe
2019-11-13 21:32 ` [PATCH 2/3] io-wq: ensure we have a stable view of ->cur_work for cancellations Jens Axboe
2019-11-13 21:32 ` [PATCH 3/3] io-wq: ensure free/busy list browsing see all items Jens Axboe
2019-11-13 23:42 ` Paul E. McKenney
2019-11-14 2:51 ` Jens Axboe [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 \
[email protected] \
[email protected] \
[email protected] \
[email protected] \
/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