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Date: Tue, 3 Feb 2009 07:29:39 +1300
Message-ID: <cfd18e0f0902021029q6ccc5bd1q291582525ca54a2b@mail.gmail.com>
Subject: Re: [Bugme-new] [Bug 12562] New: High overhead while switching or 
	synchronizing threads on different cores
From: Michael Kerrisk <mtk.manpages@googlemail.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>, Thomas Pilarski <thomas.pi@arcor.de>,
       Andrew Morton <akpm@linux-foundation.org>,
       Gregory Haskins <ghaskins@novell.com>, bugme-daemon@bugzilla.kernel.org,
       linux-kernel@vger.kernel.org
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Hi Peter,

On Tue, Feb 3, 2009 at 1:15 AM, Peter Zijlstra <peterz@infradead.org> wrote:
> On Mon, 2009-02-02 at 09:55 +0100, Peter Zijlstra wrote:
>
>> Ah, that was a good clue, apparently all you need to so it use
>> random_r() and provide your own state and all should be well.
>
> Michael, would it make sense to add the random_r() family to the "SEE
> ALSO" section of the random() man page?
>
> (Admittedly, my random() manpage is ancient: 2008-03-07, so it might be
> this is already the case, in which case, ignore me :)

(Up-to-date version of the pages can always be found online at the
location in the .sig.)

Well, the man page already had this text under notes:

       This  function  should  not  be  used  in  cases where multiple
       threads use random() and the behavior should  be  reproducible.
       Use random_r(3) for that purpose.

But it certainly doesn't hurt to have random_r(3) also listed under
the SEE ALSO, and I've added it for man-pages-3.18.

Cheers,

Michael


-- 
Michael Kerrisk
Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/
git://git.kernel.org/pub/scm/docs/man-pages/man-pages.git
man-pages online: http://www.kernel.org/doc/man-pages/online_pages.html
Found a bug? http://www.kernel.org/doc/man-pages/reporting_bugs.html