Re: [Qemu-devel] Do we need CONFIG_AIO?

["Todd T. Fries" <qemu-devel@email.fries.net>]

Penned by Avi Kivity on 20090525 16:47.14, we have:
> 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.

If thats the way things work, great.  I just recall when AIO made its debut
in qemu we had to figure out some strange workarounds..
-- 
Todd Fries .. todd@fries.net

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