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Message-ID: <8e9bf420-0405-fd71-826d-7924528f2d09@kernel.dk>
Date:   Fri, 6 May 2022 15:29:26 -0600
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Subject: Re: [PATCH 5/5] io_uring: implement multishot mode for accept
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From:   Jens Axboe <axboe@kernel.dk>
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>
 <20220506070102.26032-6-haoxu.linux@gmail.com>
 <3b302e60-cb5a-a193-db13-5ca0ef5603cc@kernel.dk>
In-Reply-To: <3b302e60-cb5a-a193-db13-5ca0ef5603cc@kernel.dk>
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On 5/6/22 2:50 PM, Jens Axboe wrote:
> On 5/6/22 1:01 AM, Hao Xu wrote:
>> @@ -5748,8 +5758,12 @@ static int io_accept(struct io_kiocb *req, unsigned int issue_flags)
>>  		if (!fixed)
>>  			put_unused_fd(fd);
>>  		ret = PTR_ERR(file);
>> -		if (ret == -EAGAIN && force_nonblock)
>> -			return -EAGAIN;
>> +		if (ret == -EAGAIN && force_nonblock) {
>> +			if ((req->flags & REQ_F_APOLL_MULTI_POLLED) ==
>> +			    REQ_F_APOLL_MULTI_POLLED)
>> +				ret = 0;
>> +			return ret;
> 
> FWIW, this
> 
> 	if ((req->flags & REQ_F_APOLL_MULTI_POLLED) == REQ_F_APOLL_MULTI_POLLED)
> 
> is identical to
> 
> 	if (req->flags & REQ_F_APOLL_MULTI_POLLED)
> 
> but I suspect this used to check more flags (??), because as it stands
> it seems a bit nonsensical.

Looking deeper, it is indeed a mask and not a single flag! So the check
looks fine.

-- 
Jens Axboe