public inbox for [email protected]
 help / color / mirror / Atom feed
From: Jens Axboe <[email protected]>
To: Hao Xu <[email protected]>
Cc: [email protected], Pavel Begunkov <[email protected]>,
	Joseph Qi <[email protected]>
Subject: Re: [PATCH 1/3] io-wq: clean code of task state setting
Date: Thu, 5 Aug 2021 08:23:55 -0600	[thread overview]
Message-ID: <[email protected]> (raw)
In-Reply-To: <[email protected]>

On 8/5/21 4:05 AM, Hao Xu wrote:
> We don't need to set task state to TASK_INTERRUPTIBLE at the beginning
> of while() in io_wqe_worker(), which causes state resetting to
> TASK_RUNNING in other place. Move it to above schedule_timeout() and
> remove redundant task state settings.

Not sure that is safe - the reason why the state is manipulated is to
guard from races where we do:

A				B
if (!work_available)
				Work inserted
schedule();

As long as setting the task runnable is part of the work being inserted,
then the above race is fine, as the schedule() turns into a no-op.

-- 
Jens Axboe


  reply	other threads:[~2021-08-05 14:25 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-08-05 10:05 [PATCH 0/3] code clean and nr_worker fixes Hao Xu
2021-08-05 10:05 ` [PATCH 1/3] io-wq: clean code of task state setting Hao Xu
2021-08-05 14:23   ` Jens Axboe [this message]
2021-08-05 17:37     ` Hao Xu
2021-08-05 10:05 ` [PATCH 2/3] io-wq: fix no lock protection of acct->nr_worker Hao Xu
2021-08-06 14:27   ` Jens Axboe
2021-08-07  9:56     ` Hao Xu
2021-08-07 13:51       ` Jens Axboe
2021-08-09 20:19         ` Olivier Langlois
2021-08-09 20:34           ` Pavel Begunkov
2021-08-09 20:35           ` Jens Axboe
2021-08-05 10:05 ` [PATCH 3/3] io-wq: fix lack of acct->nr_workers < acct->max_workers judgement Hao Xu
2021-08-05 14:58 ` [PATCH 0/3] code clean and nr_worker fixes Jens Axboe

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] \
    [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