diff options
| author | John Fastabend | 2017-03-28 18:47:03 +0200 |
|---|---|---|
| committer | Jeff Kirsher | 2017-04-30 05:01:02 +0200 |
| commit | 7379f97a4fce3c1aa3b80a85cb8440453bf30411 (patch) | |
| tree | a6ec4bd7dd56bd8eaa74d9ce319ee3e38a9789d3 /drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | |
| parent | ixgbe: add support for XDP_TX action (diff) | |
| download | kernel-qcow2-linux-7379f97a4fce3c1aa3b80a85cb8440453bf30411.tar.gz kernel-qcow2-linux-7379f97a4fce3c1aa3b80a85cb8440453bf30411.tar.xz kernel-qcow2-linux-7379f97a4fce3c1aa3b80a85cb8440453bf30411.zip | |
ixgbe: delay tail write to every 'n' packets
Current XDP implementation hits the tail on every XDP_TX return
code. This patch changes driver behavior to only hit the tail after
packet processing is complete.
With this patch I can run XDP drop programs @ 14+Mpps and XDP_TX
programs are at ~13.5Mpps.
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Diffstat (limited to 'drivers/net/ethernet/intel/ixgbe/ixgbe_main.c')
| -rw-r--r-- | drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 28 |
1 files changed, 17 insertions, 11 deletions
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c index cb5be7de2c91..3d7b09100945 100644 --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c @@ -2283,6 +2283,7 @@ static int ixgbe_clean_rx_irq(struct ixgbe_q_vector *q_vector, unsigned int mss = 0; #endif /* IXGBE_FCOE */ u16 cleaned_count = ixgbe_desc_unused(rx_ring); + bool xdp_xmit = false; while (likely(total_rx_packets < budget)) { union ixgbe_adv_rx_desc *rx_desc; @@ -2322,10 +2323,12 @@ static int ixgbe_clean_rx_irq(struct ixgbe_q_vector *q_vector, } if (IS_ERR(skb)) { - if (PTR_ERR(skb) == -IXGBE_XDP_TX) + if (PTR_ERR(skb) == -IXGBE_XDP_TX) { + xdp_xmit = true; ixgbe_rx_buffer_flip(rx_ring, rx_buffer, size); - else + } else { rx_buffer->pagecnt_bias++; + } total_rx_packets++; total_rx_bytes += size; } else if (skb) { @@ -2393,6 +2396,16 @@ static int ixgbe_clean_rx_irq(struct ixgbe_q_vector *q_vector, total_rx_packets++; } + if (xdp_xmit) { + struct ixgbe_ring *ring = adapter->xdp_ring[smp_processor_id()]; + + /* Force memory writes to complete before letting h/w + * know there are new descriptors to fetch. + */ + wmb(); + writel(ring->next_to_use, ring->tail); + } + u64_stats_update_begin(&rx_ring->syncp); rx_ring->stats.packets += total_rx_packets; rx_ring->stats.bytes += total_rx_bytes; @@ -8238,14 +8251,8 @@ static int ixgbe_xmit_xdp_ring(struct ixgbe_adapter *adapter, tx_desc->read.olinfo_status = cpu_to_le32(len << IXGBE_ADVTXD_PAYLEN_SHIFT); - /* Force memory writes to complete before letting h/w know there - * are new descriptors to fetch. (Only applicable for weak-ordered - * memory model archs, such as IA-64). - * - * We also need this memory barrier to make certain all of the - * status bits have been updated before next_to_watch is written. - */ - wmb(); + /* Avoid any potential race with xdp_xmit and cleanup */ + smp_wmb(); /* set next_to_watch value indicating a packet is present */ i++; @@ -8255,7 +8262,6 @@ static int ixgbe_xmit_xdp_ring(struct ixgbe_adapter *adapter, tx_buffer->next_to_watch = tx_desc; ring->next_to_use = i; - writel(i, ring->tail); return IXGBE_XDP_TX; } |