Re: [Qemu-devel] [RFC] create a single workqueue for each vm to update vm irq routing table

Avi Kivity
2013-11-28T11:33:22Z

On 11/28/2013 01:31 PM, Paolo Bonzini wrote:
> Il 28/11/2013 12:23, Gleb Natapov ha scritto:
>>>>>> Unless what ? :) Unless reader is scheduled out?
>>>> Yes. Or unless my brain is scheduled out in the middle of a sentence.
>>>>
>> So we will have to disable preemption in a reader to prevent big latencies for
>> a writer, no?
> I don't think that's necessary. The writer itself could also be
> scheduled out, and the reader critical sections are really small. Let's
> wait for Zhang to try SRCU and report back.
>

I think readers have preemption disabled already in that context (irqfd
writes).