intel-ethernet: software timestamp skbs as late as possible

Many of the Intel Ethernet drivers call skb_tx_timestamp() earlier than
necessary. Move the calls to this function to the latest point possible,
just prior to notifying hardware of the new Tx packet when we bump the
tail register.

This affects i40e, iavf, igb, igc, and ixgbe.

The e100, e1000, e1000e, fm10k, and ice drivers already call the
skb_tx_timestamp() function just prior to indicating the Tx packet to
hardware, so they do not need to be changed.

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/drivers/net/ethernet/intel/igc/igc_main.c b/drivers/net/ethernet/intel/igc/igc_main.c
index 9d85707e8a81..615a5fcd5a00 100644
--- a/drivers/net/ethernet/intel/igc/igc_main.c
+++ b/drivers/net/ethernet/intel/igc/igc_main.c
@@ -865,6 +865,8 @@ static int igc_tx_map(struct igc_ring *tx_ring,
         /* set the timestamp */
         first->time_stamp = jiffies;
 
+        skb_tx_timestamp(skb);
+
         /* 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).
@@ -959,8 +961,6 @@ static netdev_tx_t igc_xmit_frame_ring(struct sk_buff *skb,
         first->bytecount = skb->len;
         first->gso_segs = 1;
 
-        skb_tx_timestamp(skb);
-
         /* record initial flags and protocol */
         first->tx_flags = tx_flags;
         first->protocol = protocol;