igb: move gso_segs into buffer_info structure

This change moves gso_segs into the buffer_info structure to avoid
a possible cache line miss in clean_tx_irq.

Signed-off-by: Nicholas Nunley <nicholasx.d.nunley@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/igb/igb.h b/drivers/net/igb/igb.h
index 8f07bc0a1d4c72068e913979b5ef1ad058405651..7854b66648c7763b9ae659a9cf0820d361887a75 100644 (file)
--- a/drivers/net/igb/igb.h
+++ b/drivers/net/igb/igb.h
@@ -141,6 +141,7 @@ struct igb_buffer {
                        u16 length;
                        u16 next_to_watch;
                        u16 mapped_as_page;
+                       u16 gso_segs;
                };
                /* RX */
                struct {

diff --git a/drivers/net/igb/igb_main.c b/drivers/net/igb/igb_main.c
index a1fe581febc0baf95066cf3bd76b3d33a8c2ca8c..91c123f9df92f15baa508d7f1ffdfb7ec818c5b5 100644 (file)
--- a/drivers/net/igb/igb_main.c
+++ b/drivers/net/igb/igb_main.c
@@ -3641,6 +3641,7 @@ static inline int igb_tx_map_adv(struct igb_ring *tx_ring, struct sk_buff *skb,
        }
 
        tx_ring->buffer_info[i].skb = skb;
+       tx_ring->buffer_info[i].gso_segs = skb_shinfo(skb)->gso_segs ?: 1;
        tx_ring->buffer_info[first].next_to_watch = i;
 
        return ++count;
@@ -5032,7 +5033,7 @@ static bool igb_clean_tx_irq(struct igb_q_vector *q_vector)
                        if (skb) {
                                unsigned int segs, bytecount;
                                /* gso_segs is currently only valid for tcp */
-                               segs = skb_shinfo(skb)->gso_segs ?: 1;
+                               segs = buffer_info->gso_segs;
                                /* multiply data chunks by size of headers */
                                bytecount = ((segs - 1) * skb_headlen(skb)) +
                                            skb->len;