Re: [PATCH v3] io_uring: don't wait when under-submitting

From: Jens Axboe
Date: Sat Dec 14 2019 - 13:43:49 EST


On 12/14/19 7:53 AM, Pavel Begunkov wrote:
> There is no reliable way to submit and wait in a single syscall, as
> io_submit_sqes() may under-consume sqes (in case of an early error).
> Then it will wait for not-yet-submitted requests, deadlocking the user
> in most cases.
>
> In such cases adjust min_complete, so it won't wait for more than
> what have been submitted in the current call to io_uring_enter(). It
> may be less than totally in-flight including previous submissions,
> but this shouldn't do harm and up to a user.

Thanks, applied.

--
Jens Axboe