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Date: Mon, 25 May 2009 16:47:14 +0300
From: Avi Kivity <avi@redhat.com>
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Subject: Re: [Qemu-devel] Do we need CONFIG_AIO?
References: <20090525082151.GA4107@lst.de> <4A1A85B4.3060200@eu.citrix.com>
	<20090525133554.GA16351@fries.net>
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To: todd@fries.net
Cc: "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>, Christoph Hellwig <hch@lst.de>, Stefano Stabellini <stefano.stabellini@eu.citrix.com>

Todd T. Fries wrote:
> Penned by Stefano Stabellini on 20090525 12:49.08, we have:
> | Christoph Hellwig wrote:
> | 
> | > Currently all aio code in the raw-posix block driver depends on a
> | > CONFIG_AIO symbol that gets set based on the availability of the
> | > pthreads library.  Beeing able to rely on unconditional aio support
> | > means we could remove the whole code for plain bdrv_read/bdrv_write
> | > in raw-posix.c which is about 300 lines of code and a duplicated code
> | > path.  Is there any Posix-ish platform qemu supports that does not
> | > have pthreads support?
> | > 
> | 
> | MiniOS.
> | I would appreciate if you keep that flag.
>
> You seem to be under the illusion that pthreads implies AIO.
>   

He isn't.

> OpenBSD has two flavors of threads libraries (arguably one is not
> fit for consumption yet) and neither provide AIO.
>
> This flag is most useful for OpenBSD as well.
>   

Qemu's CONFIG_AIO requires thread support from the host, not posix aio 
support.

-- 
error compiling committee.c: too many arguments to function