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Date: Fri, 16 Feb 2001 15:29:14 +0100
From: Andrea Arcangeli <andrea@suse.de>
To: Andi Kleen <ak@suse.de>
Cc: Roman Zippel <zippel@fh-brandenburg.de>,
        Timur Tabi <ttabi@interactivesi.com>, linux-kernel@vger.kernel.org
Subject: Re: [ANNOUNCE] Kernel Janitor's TODO list
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In-Reply-To: <20010129213553.A6552@gruyere.muc.suse.de>; from ak@suse.de on Mon, Jan 29, 2001 at 09:35:53PM +0100
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On Mon, Jan 29, 2001 at 09:35:53PM +0100, Andi Kleen wrote:
> On Mon, Jan 29, 2001 at 08:47:50PM +0100, Roman Zippel wrote:
> > You still miss wakeups. :)
> 
> And there was another race in it, I know.  The first __set_task_state
> has to be set_task_state to get the right memory write order on SMP. 

If the wakeup is serialized by the spinlock too (as your code looks like to
assume) you can legally use __set_task_state instead of set_task_state.  An
example of such an usage (where wakeup is serialized by the spinlock) is
lock_sock/unlock_sock.

Andrea