sfc: batch up RX delivery

Improves packet rate of 1-byte UDP receives by up to 10%.

Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/sfc/efx.c b/drivers/net/ethernet/sfc/efx.c
index 570ec72266f37cac1626eb8358ffbf21bb536192..b24c2e21db8e9df6eb1abd283c084858113bbe37 100644 (file)
--- a/drivers/net/ethernet/sfc/efx.c
+++ b/drivers/net/ethernet/sfc/efx.c
@@ -264,11 +264,17 @@ static int efx_check_disabled(struct efx_nic *efx)
 static int efx_process_channel(struct efx_channel *channel, int budget)
 {
        struct efx_tx_queue *tx_queue;
+       struct list_head rx_list;
        int spent;
 
        if (unlikely(!channel->enabled))
                return 0;
 
+       /* Prepare the batch receive list */
+       EFX_WARN_ON_PARANOID(channel->rx_list != NULL);
+       INIT_LIST_HEAD(&rx_list);
+       channel->rx_list = &rx_list;
+
        efx_for_each_channel_tx_queue(tx_queue, channel) {
                tx_queue->pkts_compl = 0;
                tx_queue->bytes_compl = 0;
@@ -291,6 +297,10 @@ static int efx_process_channel(struct efx_channel *channel, int budget)
                }
        }
 
+       /* Receive any packets we queued up */
+       netif_receive_skb_list(channel->rx_list);
+       channel->rx_list = NULL;
+
        return spent;
 }
 
@@ -555,6 +565,8 @@ static int efx_probe_channel(struct efx_channel *channel)
                        goto fail;
        }
 
+       channel->rx_list = NULL;
+
        return 0;
 
 fail:

diff --git a/drivers/net/ethernet/sfc/net_driver.h b/drivers/net/ethernet/sfc/net_driver.h
index 65568925c3efe6398d1e26ca1520b53919f60291..961b9297964069440a962e39cd409760b71c073a 100644 (file)
--- a/drivers/net/ethernet/sfc/net_driver.h
+++ b/drivers/net/ethernet/sfc/net_driver.h
@@ -448,6 +448,7 @@ enum efx_sync_events_state {
  *     __efx_rx_packet(), or zero if there is none
  * @rx_pkt_index: Ring index of first buffer for next packet to be delivered
  *     by __efx_rx_packet(), if @rx_pkt_n_frags != 0
+ * @rx_list: list of SKBs from current RX, awaiting processing
  * @rx_queue: RX queue for this channel
  * @tx_queue: TX queues for this channel
  * @sync_events_state: Current state of sync events on this channel
@@ -500,6 +501,8 @@ struct efx_channel {
        unsigned int rx_pkt_n_frags;
        unsigned int rx_pkt_index;
 
+       struct list_head *rx_list;
+
        struct efx_rx_queue rx_queue;
        struct efx_tx_queue tx_queue[EFX_TXQ_TYPES];
 

diff --git a/drivers/net/ethernet/sfc/rx.c b/drivers/net/ethernet/sfc/rx.c
index d2e254f2f72bf0f2fffd0078397da819a676980f..396ff01298cdfd4d8ccc5566e36dba778a7f4e59 100644 (file)
--- a/drivers/net/ethernet/sfc/rx.c
+++ b/drivers/net/ethernet/sfc/rx.c
@@ -634,7 +634,12 @@ static void efx_rx_deliver(struct efx_channel *channel, u8 *eh,
                        return;
 
        /* Pass the packet up */
-       netif_receive_skb(skb);
+       if (channel->rx_list != NULL)
+               /* Add to list, will pass up later */
+               list_add_tail(&skb->list, channel->rx_list);
+       else
+               /* No list, so pass it up now */
+               netif_receive_skb(skb);
 }
 
 /* Handle a received packet.  Second half: Touches packet payload. */