Re: [Qemu-devel] [RFC 0/8] arm AioContext with its own timer stuff

[Jan Kiszka]

On 2013-07-25 14:35, Paolo Bonzini wrote:
> Il 25/07/2013 14:32, Jan Kiszka ha scritto:
>> On 2013-07-25 14:21, Alex Bligh wrote:
>>>
>>>
>>> --On 25 July 2013 14:05:30 +0200 Stefan Hajnoczi <address@hidden>
>>> wrote:
>>>
>>>> Alex Bligh's series gives each AioContext its own rt_clock.  This avoids
>>>> the need for synchronization in the simple case.  If we require timer
>>>> access between threads then we really need to synchronize.
>>>>
>>>> You pointed out in another email that vm_clock stops when the guest is
>>>> paused.  I think we can find a solution for I/O throttling and QED,
>>>> which use vm_clock in the block layer.  Note that block jobs already use
>>>> rt_clock.
>>>
>>> I would happily at a QEMUClock of each type to AioContext. They are after
>>> all pretty lightweight.
>>
>> What's the point of adding tones of QEMUClock instances? Considering
>> proper abstraction, how are they different for each AioContext? Will
>> they run against different clock sources, start/stop at different times?
>> If the answer is "they have different timer list", then fix this
>> incorrect abstraction.
> 
> s/QEMUClock/QEMUTimerList/ ? :)

What do you mean? If the content of struct QEMUClock remained the same,
that would just paper over a design mistake.

Jan

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