Re: [Qemu-devel] Block layer roadmap

[Stefan Hajnoczi]

On Thu, Jul 28, 2011 at 2:10 PM, Kevin Wolf <address@hidden> wrote:
> Am 28.07.2011 14:54, schrieb Stefan Hajnoczi:
>> On Thu, Jul 28, 2011 at 1:35 PM, Kevin Wolf <address@hidden> wrote:
>>> Am 28.07.2011 14:09, schrieb Christoph Hellwig:
>>>> On Wed, Jul 27, 2011 at 01:37:31PM +0100, Stefan Hajnoczi wrote:
>>>>> Coroutines in the block layer [Kevin]
>>>>>  * Programming model to simplify block drivers without blocking QEMU 
>>>>> threads
>>>>
>>>> Can anyone explain what the whole point of this is?  It really just is
>>>> a bit of syntactic sugar for the current async state machines.  What does
>>>> it buy us over going for real threading?
>>>
>>> The only current block driver that really does everything in an async
>>> state machine is qed. It's definitely not nice code, and having to
>>> convert all of the other block drivers to this would be a lot of work.
>>
>> Thanks Kevin :).
>
> I certainly didn't mean to attack your code or even yourself. It's not
> that qed is done particularly bad or anything. That the code isn't
> really nice is just the natural result of the callback-based programming
> model.

No worries, no offence taken :)

Stefan