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Date: Tue, 16 Sep 2008 20:50:27 +0300
From: "Blue Swirl" <blauwirbel@gmail.com>
Subject: Re: [Qemu-devel] [PATCH] Refactor AIO to allow multiple AIO
	implementations
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To: qemu-devel@nongnu.org
Cc: Anthony Liguori <aliguori@us.ibm.com>, Ryan Harper <ryanh@us.ibm.com>, kvm@vger.kernel.org

On 9/16/08, Anthony Liguori <aliguori@us.ibm.com> wrote:
> This patch refactors the AIO layer to allow multiple AIO implementations.  It's
>  only possible because of the recent signalfd() patch.

>  +/* This is a simple lock used to protect the aio_handlers list.  Specifically,
>  + * it's used to ensure that no callbacks are removed while we're walking and
>  + * dispatching callbacks.
>  + */
>  +static int walking_handlers;

Shouldn't this be volatile and/or atomic_t?

Just wondering, why don't you use real locking operations, for example
those in qemu-lock.h?