[RFC PATCH v2 net-next 02/12] sfc: batch up RX delivery
From: Edward Cree <hidden>
Date: 2018-06-26 18:17:39
Subsystem:
networking drivers, sfc network driver, the rest · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Edward Cree, Linus Torvalds
Improves packet rate of 1-byte UDP receives by up to 10%. Signed-off-by: Edward Cree <redacted> --- drivers/net/ethernet/sfc/efx.c | 12 ++++++++++++ drivers/net/ethernet/sfc/net_driver.h | 3 +++ drivers/net/ethernet/sfc/rx.c | 7 ++++++- 3 files changed, 21 insertions(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/sfc/efx.c b/drivers/net/ethernet/sfc/efx.c
index ad4a354ce570..e84e4437dbbd 100644
--- 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 sk_buff_head rx_list; int spent; if (unlikely(!channel->enabled)) return 0; + /* Prepare the batch receive list */ + EFX_WARN_ON_PARANOID(channel->rx_list != NULL); + channel->rx_list = &rx_list; + __skb_queue_head_init(channel->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 65568925c3ef..e1d3ca3b90b5 100644
--- 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 sk_buff_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 d2e254f2f72b..3e4d67d2d45d 100644
--- 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 */ + __skb_queue_tail(channel->rx_list, skb); + else + /* No list, so pass it up now */ + netif_receive_skb(skb); } /* Handle a received packet. Second half: Touches packet payload. */