Messages in this thread Patch in this message | | | Subject | Re: [PATCH net-next v7 8/9] xen-netback: Timeout packets in RX path | From | Ian Campbell <> | Date | Thu, 13 Mar 2014 10:39:03 +0000 |
| |
On Thu, 2014-03-06 at 21:48 +0000, Zoltan Kiss wrote: > @@ -557,12 +577,25 @@ void xenvif_disconnect(struct xenvif *vif) > void xenvif_free(struct xenvif *vif) > { > int i, unmap_timeout = 0; > + /* Here we want to avoid timeout messages if an skb can be legitimatly
"legitimately"
> + * stucked somewhere else. Realisticly this could be an another vif's
"stuck" and "Realistically"
> + * internal or QDisc queue. That another vif also has this > + * rx_drain_timeout_msecs timeout, but the timer only ditches the > + * internal queue. After that, the QDisc queue can put in worst case > + * XEN_NETIF_RX_RING_SIZE / MAX_SKB_FRAGS skbs into that another vif's > + * internal queue, so we need several rounds of such timeouts until we > + * can be sure that no another vif should have skb's from us. We are > + * not sending more skb's, so newly stucked packets are not interesting
"stuck" again.
> diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c > index 560950e..bb65c7c 100644 > --- a/drivers/net/xen-netback/netback.c > +++ b/drivers/net/xen-netback/netback.c > @@ -63,6 +63,13 @@ module_param(separate_tx_rx_irq, bool, 0644); > static unsigned int fatal_skb_slots = FATAL_SKB_SLOTS_DEFAULT; > module_param(fatal_skb_slots, uint, 0444); > > +/* When guest ring is filled up, qdisc queues the packets for us, but we have > + * to timeout them, otherwise other guests' packets can get stucked there
"stuck"
Ian.
| |