Re: [Qemu-devel] [PATCH 00/10] block: Coroutine support

[Kevin Wolf]

Am 02.08.2011 16:55, schrieb Frediano Ziglio:
> 2011/8/2 Kevin Wolf <address@hidden>:
>> Am 02.08.2011 16:23, schrieb Avi Kivity:
>>> On 07/26/2011 02:48 PM, Kevin Wolf wrote:
>>>> Depends on Stefan's latest coroutine patches. This series makes qcow and 
>>>> qcow2
>>>> take advantage of the new coroutine infrastructure. Both formats used
>>>> synchronous operations for accessing their metadata and blocked the guest 
>>>> CPU
>>>> during that time. With coroutines, the I/O will happen asynchronously in 
>>>> the
>>>> background and the CPU won't be blocked any more.
>>>>
>>>
>>> Do you plan to convert qcow2 to a fully synchronous design?
>>>
>>> IMO that will make it more maintainable.  Cancellation will need some
>>> thought, though.
>>
>> After this patch series, all interesting paths are free of callbacks (I
>> assume this is what you mean by synchronous?). The only thing I can see
>> that is left is qcow2_aio_flush. What is required are some cleanups that
>> eliminate things that still look like AIO code, and yes, that's
>> something that I want to have.
>>
>> Frediano has posted some patches which I haven't fully reviewed yet, but
>> the qcow1 RFC he posted was definitely a step in the right direction.
>>
> 
> Did I send patches for qcow2?
> I just rebased them with your last updates, I'll send them again.

Yes, you did. I just haven't reviewed them yet. But assuming that you're
basically doing the same as in qcow1, they are the right thing to do.

Kevin