Re: [Xen-devel] [PATCH v2 09/13] xen/pvcalls: implement recvmsg

From: Boris Ostrovsky
Date: Wed Jul 26 2017 - 17:32:12 EST



>> + while (!(flags & MSG_DONTWAIT) && !pvcalls_front_read_todo(map)) {
>> + if (count < PVCALLS_FRONT_MAX_SPIN)
>> + count++;
>> + else
>> + wait_event_interruptible(map->active.inflight_conn_req,
>> + pvcalls_front_read_todo(map));
>> + }
> Should we be using PVCALLS_FRONT_MAX_SPIN here? In sendmsg it is
> counting non-sleeping iterations but here we are sleeping so
> PVCALLS_FRONT_MAX_SPIN (5000) may take a while.
>
> In fact, what shouldn't this waiting be a function of MSG_DONTWAIT

err, which it already is. But the question still stands (except for
MSG_DONTWAIT).

-boris

> and/or socket's O_NONBLOCK?