From: Robert Love <rml@tech9.net>
To: Linus Torvalds <torvalds@transmeta.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: [PATCH] set_cpus_allowed() atomicity fix
Date: 09 Oct 2002 21:05:17 -0400 [thread overview]
Message-ID: <1034211918.753.340.camel@phantasy> (raw)
In-Reply-To: <Pine.LNX.4.44.0210091615540.9234-100000@home.transmeta.com>
On Wed, 2002-10-09 at 19:17, Linus Torvalds wrote:
> On 9 Oct 2002, Robert Love wrote:
> >
> > Anyhow, attached patch fixes the atomicity debugging error.
>
> I don't think this is right. You have to be preempt safe over the whole
> time you're holding the "rq" pointer, I think. Otherwise you might move to
> another CPU, at which point the rq state isn't valid any more. Or maybe I
> misunderstood.
I agree. But aren't we?
We are preempt-safe through the entire function (starting at the top
with task_rq_lock()) until the preempt_disable(). The only instruction
outside of the critical section is the wait_for_completion() which
sleeps anyhow.
Or maybe _I_ misunderstood?
Robert Love
prev parent reply other threads:[~2002-10-10 0:59 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2002-10-09 23:05 [PATCH] set_cpus_allowed() atomicity fix Robert Love
2002-10-09 23:17 ` Linus Torvalds
2002-10-10 1:05 ` Robert Love [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 \
--in-reply-to=1034211918.753.340.camel@phantasy \
--to=rml@tech9.net \
--cc=linux-kernel@vger.kernel.org \
--cc=torvalds@transmeta.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox