Re: [RFC] block/nbd: Move s->ioc on AioContext change

[Vladimir Sementsov-Ogievskiy]

01.02.2022 19:14, Hanna Reitz wrote:
> > > reconnect_delay_timer should exist only during IO request: it's created during 
> > > request if we don't have a connection. And request will not finish until timer 
> > > elapsed or connection established (timer should be removed in this case too). 
> > > So, again, when attaching / detaching the context we should be in a drained 
> > > sections, so no in-flight requests and no reconnect_delay_timer.
> >
> > Got it.  FWIW, other block drivers rely on this, too (e.g. null-aio with 
> > latency-ns set creates a timer in every I/O request and settles the request 
> > once the timer expires).
>
> Looks like the timer isn’t removed when the connection is reestablished.

Oops. And that's wrong.. If connection lost again when old timer is still not 
fired, assertion in reconnect_delay_timer_init() will fail.

I think we just need reconnect_delay_timer_del() call at the end of 
nbd_reconnect_attempt() function (after nbd_co_do_establish_connection() call).


--
Best regards,
Vladimir