On 6/22/21 8:05 PM, Olivier Langlois wrote:
> On Tue, 2021-06-22 at 19:01 +0100, Pavel Begunkov wrote:
>> On 6/22/21 6:54 PM, Pavel Begunkov wrote:
>>> On 6/22/21 1:17 PM, Olivier Langlois wrote:
>>>>
>>>
>>>> static bool __io_poll_remove_one(struct io_kiocb *req,
>>>> @@ -6437,6 +6445,7 @@ static void __io_queue_sqe(struct io_kiocb
>>>> *req)
>>>> struct io_kiocb *linked_timeout =
>>>> io_prep_linked_timeout(req);
>>>> int ret;
>>>>
>>>> +issue_sqe:
>>>> ret = io_issue_sqe(req,
>>>> IO_URING_F_NONBLOCK|IO_URING_F_COMPLETE_DEFER);
>>>>
>>>> /*
>>>> @@ -6456,12 +6465,16 @@ static void __io_queue_sqe(struct
>>>> io_kiocb *req)
>>>> io_put_req(req);
>>>> }
>>>> } else if (ret == -EAGAIN && !(req->flags &
>>>> REQ_F_NOWAIT)) {
>>>> - if (!io_arm_poll_handler(req)) {
>>>> + switch (io_arm_poll_handler(req)) {
>>>> + case IO_APOLL_READY:
>>>> + goto issue_sqe;
>>>> + case IO_APOLL_ABORTED:
>>>> /*
>>>> * Queued up for async execution, worker
>>>> will release
>>>> * submit reference when the iocb is
>>>> actually submitted.
>>>> */
>>>> io_queue_async_work(req);
>>>> + break;
>>>
>>> Hmm, why there is a new break here? It will miscount
>>> @linked_timeout
>>> if you do that. Every io_prep_linked_timeout() should be matched
>>> with
>>> io_queue_linked_timeout().
>>
>> Never mind, I said some nonsense and apparently need some coffee
>
> but this is a pertinant question, imho. I guess that you could get away
It appeared to me that it doesn't go down to the end of the function
but returns or so, that's the nonsense part.
> without it since it is the last case of the switch statement... I am
> not sure what kernel coding standard says about that.
breaks are preferable, and falling through should be explicitly
marked with fallthrough;
> However, I can tell you that there was also a break statement at the
> end of the case for IO_APOLL_READY and checkpatch.pl did complain about
> it saying that it was useless since it was following a goto statement.
> Therefore, I did remove that one.
>
> checkpatch.pl did remain silent about the other remaining break. Hence
> this is why I left it there.
--
Pavel Begunkov
