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Message-ID: <5ce3d6c7-42f9-28c3-0800-4da399adaaea@kernel.dk>
Date:   Fri, 6 May 2022 08:18:59 -0600
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Subject: Re: [PATCH v2 0/5] 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: <20220506070102.26032-1-haoxu.linux@gmail.com>
 <b4d23f42-36f4-353a-1f44-c12178f0a2b3@gmail.com>
From:   Jens Axboe <axboe@kernel.dk>
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On 5/6/22 1:36 AM, Hao Xu wrote:
> Hi All,
> I actually had a question about the current poll code, from the code it
> seems when we cancel a poll-like request, it will ignore the existing
> events and just raise a -ECANCELED cqe though I haven't tested it. Is
> this by design or am I missing something?

That's by design, but honestly I don't think anyone considered the case
where it's being canceled but has events already. For that case, I think
we should follow the usual logic of only returning an error (canceled)
if we don't have events, if we have events just return them. For
multi-shot, obviously also terminate, but same logic there.

Care to do a separate patch for that?

-- 
Jens Axboe