All of lore.kernel.org
 help / color / mirror / Atom feed
From: Rusty Russell <rusty@rustcorp.com.au>
To: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
	linux-kernel@vger.kernel.org,
	Nick Piggin <nickpiggin@yahoo.com.au>,
	Ingo Molnar <mingo@elte.hu>,
	"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
	Peter Zijlstra <a.p.zijlstra@chello.nl>,
	Andy Whitcroft <apw@shadowen.org>
Subject: Re: [PATCH 1/2] kthread: add a missing memory barrier to kthread_stop()
Date: Mon, 3 Mar 2008 08:50:56 +1100	[thread overview]
Message-ID: <200803030850.57615.rusty@rustcorp.com.au> (raw)
In-Reply-To: <1203543390.6307.24.camel@earth>

On Thursday 21 February 2008 08:36:30 Dmitry Adamushko wrote:
> From: Dmitry Adamushko <dmitry.adamushko@gmail.com>
> Subject: kthread: add a missing memory barrier to kthread_stop()
>
> We must ensure that kthread_stop_info.k has been updated before
> kthread's wakeup. This is required to properly support
> the use of kthread_should_stop() in the main loop of kthread.
>
> wake_up_process() doesn't imply a full memory barrier,
> so we add an explicit one.

I always believed that wake_up_process() implies a write barrier.  It's pretty 
common to set something up then wake the intended recipient.

So I think this patch is overkill, but I'm happy to be corrected.

Thanks!
Rusty.

  reply	other threads:[~2008-03-02 21:51 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-02-20 21:36 [PATCH 1/2] kthread: add a missing memory barrier to kthread_stop() Dmitry Adamushko
2008-03-02 21:50 ` Rusty Russell [this message]
2008-03-02 22:28   ` Dmitry Adamushko

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=200803030850.57615.rusty@rustcorp.com.au \
    --to=rusty@rustcorp.com.au \
    --cc=a.p.zijlstra@chello.nl \
    --cc=akpm@linux-foundation.org \
    --cc=apw@shadowen.org \
    --cc=dmitry.adamushko@gmail.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@elte.hu \
    --cc=nickpiggin@yahoo.com.au \
    --cc=paulmck@linux.vnet.ibm.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 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.