Re: [RFC v3 4/5] KVM: add ioregionfd context

Paolo Bonzini
2021-03-10T14:12:52Z

On 10/03/21 14:20, Elena Afanasova wrote:
> On Tue, 2021-03-09 at 09:01 +0100, Paolo Bonzini wrote:
>> On 09/03/21 08:54, Jason Wang wrote:
>>>> + return;
>>>> +
>>>> + spin_lock(&ctx->wq.lock);
>>>> + wait_event_interruptible_exclusive_locked(ctx->wq, !ctx-
>>>>> busy);
>>>
>>> Any reason that a simple mutex_lock_interruptible() can't work
>>> here?
>>
>> Or alternatively why can't the callers just take the spinlock.
>>
> I'm not sure I understand your question. Do you mean why locked version
> of wait_event() is used?

No, I mean why do you need to use ctx->busy and wait_event, instead of
operating directly on the spinlock or on a mutex.

Paolo