On 09/07/2020 16:53, Matthew Wilcox wrote:
> On Thu, Jul 09, 2020 at 04:49:51PM +0300, Pavel Begunkov wrote:
>> On 09/07/2020 16:43, Matthew Wilcox wrote:
>>> On Thu, Jul 09, 2020 at 04:37:59PM +0300, Pavel Begunkov wrote:
>>>> Kanchan, could you take a look if you can hide it in req->cflags?
>>>
>>> No, that's not what cflags are for. And besides, there's only 32 bits
>>> there.
>>
>> It's there to temporarily store cqe->cflags, if a request can't completed
>> right away. And req->{result,user_data,cflags} are basically an CQE inside
>> io_kiocb.
>>
>> So, it is there exactly for that reason, and whatever way it's going to be
>> encoded in an CQE, io_kiocb can fit it. That was my point.
>
> But it's not going to be encoded in the CQE. Perhaps you should go back to
> the older thread and read the arguments there.
Ok, if the thread is stopped on the version with indirection. I just looked the
last sent patch.
If so, we can also store offset before adding an CQE and getting by with local
vars only. Just a thought.
--
Pavel Begunkov
