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Date:   Sun, 8 May 2022 06:49:24 -0600
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Subject: Re: [PATCH v3 0/4] fast poll multishot mode
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To:     Hao Xu <haoxu.linux@gmail.com>, io-uring@vger.kernel.org
Cc:     Pavel Begunkov <asml.silence@gmail.com>,
        linux-kernel@vger.kernel.org
References: <20220507140620.85871-1-haoxu.linux@gmail.com>
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 <0b52bbd2-56de-c213-df3f-73f0f83a1f3a@gmail.com>
From:   Jens Axboe <axboe@kernel.dk>
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On 5/7/22 11:21 AM, Hao Xu wrote:
> 在 2022/5/8 上午12:11, Jens Axboe 写道:
>> On 5/7/22 10:05 AM, Hao Xu wrote:
>>>> But we still need to consider direct accept with multishot... Should
>>>> probably be an add-on patch as I think it'd get a bit more complicated
>>>> if we need to be able to cheaply find an available free fixed fd slot.
>>>> I'll try and play with that.
>>>
>>> I'm tending to use a new mail account to send v4 rather than the gmail
>>> account since the git issue seems to be network related.
>>> I'll also think about the fixed fd problem.
>>
>> Two basic attached patches that attempt do just alloc a fixed file
>> descriptor for this case. Not tested at all... We return the fixed file
>> slot in this case since we have to, to let the application know what was
>> picked. I kind of wish we'd done that with direct open/accept to begin
>> with anyway, a bit annoying that fixed vs normal open/accept behave
>> differently.
>>
>> Anyway, something to play with, and I'm sure it can be made better.
>>
> Thanks. I tried to fix the mail account issue, still unclear what is
> wrong, and too late at my timezone now, I'll try to send v4 tomorrow

No worries. IN the meantime, I played with allocated direct descriptors
yesterday and implemented them for openat/openat2/accept:

https://git.kernel.dk/cgit/linux-block/log/?h=fastpoll-mshot

It's independent of multishot accept in the sense that you can use it
without that, but multishot accept requires it with fixed files.


-- 
Jens Axboe