On Sat, Nov 14, 2015 at 11:46:58AM +0300, Slawa Olhovchenkov wrote: > On Fri, Nov 13, 2015 at 03:40:04PM -0800, Luigi Rizzo wrote: > > > On Fri, Nov 13, 2015 at 1:30 PM, Slawa Olhovchenkov <[email protected]> wrote: > > > I am see strange things: like NETMAP stop transmit after `head` and `cur` > > > touch `tail`. > > > > > > But: > > > > > > /* > > > * check if space is available in the ring. > > > */ > > > static inline int > > > nm_ring_empty(struct netmap_ring *ring) > > > { > > > return (ring->cur == ring->tail); > > > } > > > > > > i.e. if cur == (tail-1) mod ring_size -- space is available in the > > > ring and I can put packet in output buffer. > > > > The design requires to leave at least one empty slot in the buffer. > > The name of the function is correct, the comment is probably not, > > unless a bug has creeped in recently the code was very careful > > in not using the free slot that separates the two regions. > > Please, do some clarification, in case for transmit patch: > > - can I put in txring in case cur == (tail-1) mod ring_size? > - can I use poll with only `events |= POLLIN` for transmiting? > > in case for receive patch: > > - can I detect input overflow?
I am asks this questions becaus in may case don't see automatic txsync on poll: device open as np->nr_ringid = NETMAP_DO_RX_POLL; np->nr_flags = NR_REG_ALL_NIC; rc = ioctl(balancer.inside.fd, NIOCREGIF, np); poll do as pollfd[1].fd = thr->inside.fd; pollfd[1].events |= POLLIN; poll(pollfd, nfd, 1000); and I don't see output sysncing w/o pollfd[1].events |= POLLIN | POLLOUT; Only one round packet outputs I see and no slot updates. _______________________________________________ [email protected] mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to "[email protected]"
