On 3/24/22 8:34 AM, Dylan Yudaken wrote: > Do not set REQ_F_NOWAIT if the socket is non blocking. When enabled this > causes the accept to immediately post a CQE with EAGAIN, which means you > cannot perform an accept SQE on a NONBLOCK socket asynchronously. > > By removing the flag if there is no pending accept then poll is armed as > usual and when a connection comes in the CQE is posted. > > note: If multiple accepts are queued up, then when a single connection > comes in they all complete, one with the connection, and the remaining > with EAGAIN. This could be improved in the future but will require a lot > of io_uring changes. Not true - all you'd need to do is have behavior similar to EPOLLEXCLUSIVE, which we already support for separate poll. Could be done for internal poll quite easily, and _probably_ makes sense to do by default for most cases in fact. -- Jens Axboe
