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Date:   Wed, 8 Jun 2022 12:19:19 +0800
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Subject: Re: [RFC 0/5] support nonblock submission for splice pipe to pipe
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To:     Pavel Begunkov <asml.silence@gmail.com>, io-uring@vger.kernel.org
Cc:     Jens Axboe <axboe@kernel.dk>, linux-fsdevel@vger.kernel.org,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        Andrew Morton <akpm@linux-foundation.org>,
        Luis Chamberlain <mcgrof@kernel.org>,
        Kuniyuki Iwashima <kuniyu@amazon.co.jp>
References: <20220607080619.513187-1-hao.xu@linux.dev>
 <d350c35e-1d73-b2c8-5ae4-e6ead92aebba@gmail.com>
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From:   Hao Xu <hao.xu@linux.dev>
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On 6/7/22 17:27, Pavel Begunkov wrote:
> On 6/7/22 09:06, Hao Xu wrote:
>> From: Hao Xu <howeyxu@tencent.com>
>>
>> splice from pipe to pipe is a trivial case, and we can support nonblock
>> try for it easily. splice depends on iowq at all which is slow. Let's
>> build a fast submission path for it by supporting nonblock.
> 
> fwiw,
> 
> https://www.spinics.net/lists/kernel/msg3652757.html
> 

Thanks, Pavel. Seems it has been discussed for a long time but the
result remains unclear...For me, I think this patch is necessary for 
getting a good SPLICE_F_NONBLOCK user experience.