kernel/include/net/gro_cells.h, branch linux-4.1.y

ip_tunnel: Create percpu gro_cell

2015-01-18T06:56:32Z

In the ipip tunnel, the skb->queue_mapping is lost in ipip_rcv(). All skb will be queued to the same cell->napi_skbs. The gro_cell_poll is pinned to one core under load. In production traffic, we also see severe rx_dropped in the tunl iface and it is probably due to this limit: skb_queue_len(&cell->napi_skbs) > netdev_max_backlog. This patch is trying to alloc_percpu(struct gro_cell) and schedule gro_cell_poll to process the skb in the same core. Signed-off-by: Martin KaFai Lau Acked-by: Eric Dumazet Signed-off-by: David S. Miller

gro: Fix kcalloc argument order

2013-01-28T03:46:33Z

First number, then size. Signed-off-by: Joe Perches Signed-off-by: David S. Miller

net: fix a race in gro_cell_poll()

2012-12-11T17:49:53Z

Dmitry Kravkov reported packet drops for GRE packets since GRO support was added. There is a race in gro_cell_poll() because we call napi_complete() without any synchronization with a concurrent gro_cells_receive() Once bug was triggered, we queued packets but did not schedule NAPI poll. We can fix this issue using the spinlock protected the napi_skbs queue, as we have to hold it to perform skb dequeue anyway. As we open-code skb_dequeue(), we no longer need to mask IRQS, as both producer and consumer run under BH context. Bug added in commit c9e6bc644e (net: add gro_cells infrastructure) Reported-by: Dmitry Kravkov Signed-off-by: Eric Dumazet Tested-by: Dmitry Kravkov Signed-off-by: David S. Miller

net: add gro_cells infrastructure

2012-10-01T21:01:46Z

This adds a new include file (include/net/gro_cells.h), to bring GRO (Generic Receive Offload) capability to tunnels, in a modular way. Because tunnels receive path is lockless, and GRO adds a serialization using a napi_struct, I chose to add an array of up to DEFAULT_MAX_NUM_RSS_QUEUES cells, so that multi queue devices wont be slowed down because of GRO layer. skb_get_rx_queue() is used as selector. In the future, we might add optional fanout capabilities, using rxhash for example. With help from Ben Hutchings who reminded me netif_get_num_default_rss_queues() function. Signed-off-by: Eric Dumazet Cc: Ben Hutchings Signed-off-by: David S. Miller