[PATCH net-next v3] e1000e: Be drop monitor friendly

[Florian Fainelli]

e1000e_put_txbuf() can be called from normal reclamation path as well as
when a DMA mapping failure, so we need to differentiate these two cases
when freeing SKBs to be drop monitor friendly. e1000e_tx_hwtstamp_work()
and e1000_remove() are processing TX timestamped SKBs and those should
not be accounted as drops either.

Signed-off-by: Florian Fainelli <f.faine...@gmail.com>
---
Changes in v3:

- differentiate normal reclamation from TX DMA fragment mapping errors
- removed a few invalid dev_kfree_skb() replacements (those are already
  drop monitor friendly)

Changes in v2:

- make it compile

 drivers/net/ethernet/intel/e1000e/netdev.c | 18 +++++++++++-------
 1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c 
b/drivers/net/ethernet/intel/e1000e/netdev.c
index 327dfe5bedc0..cfd21858c095 100644
--- a/drivers/net/ethernet/intel/e1000e/netdev.c
+++ b/drivers/net/ethernet/intel/e1000e/netdev.c
@@ -1071,7 +1071,8 @@ static bool e1000_clean_rx_irq(struct e1000_ring 
*rx_ring, int *work_done,
 }
 
 static void e1000_put_txbuf(struct e1000_ring *tx_ring,
-                           struct e1000_buffer *buffer_info)
+                           struct e1000_buffer *buffer_info,
+                           bool drop)
 {
        struct e1000_adapter *adapter = tx_ring->adapter;
 
@@ -1085,7 +1086,10 @@ static void e1000_put_txbuf(struct e1000_ring *tx_ring,
                buffer_info->dma = 0;
        }
        if (buffer_info->skb) {
-               dev_kfree_skb_any(buffer_info->skb);
+               if (drop)
+                       dev_kfree_skb_any(buffer_info->skb);
+               else
+                       dev_consume_skb_any(buffer_info->skb);
                buffer_info->skb = NULL;
        }
        buffer_info->time_stamp = 0;
@@ -1199,7 +1203,7 @@ static void e1000e_tx_hwtstamp_work(struct work_struct 
*work)
                wmb(); /* force write prior to skb_tstamp_tx */
 
                skb_tstamp_tx(skb, &shhwtstamps);
-               dev_kfree_skb_any(skb);
+               dev_consume_skb_any(skb);
        } else if (time_after(jiffies, adapter->tx_hwtstamp_start
                              + adapter->tx_timeout_factor * HZ)) {
                dev_kfree_skb_any(adapter->tx_hwtstamp_skb);
@@ -1254,7 +1258,7 @@ static bool e1000_clean_tx_irq(struct e1000_ring *tx_ring)
                                }
                        }
 
-                       e1000_put_txbuf(tx_ring, buffer_info);
+                       e1000_put_txbuf(tx_ring, buffer_info, false);
                        tx_desc->upper.data = 0;
 
                        i++;
@@ -2421,7 +2425,7 @@ static void e1000_clean_tx_ring(struct e1000_ring 
*tx_ring)
 
        for (i = 0; i < tx_ring->count; i++) {
                buffer_info = &tx_ring->buffer_info[i];
-               e1000_put_txbuf(tx_ring, buffer_info);
+               e1000_put_txbuf(tx_ring, buffer_info, false);
        }
 
        netdev_reset_queue(adapter->netdev);
@@ -5614,7 +5618,7 @@ static int e1000_tx_map(struct e1000_ring *tx_ring, 
struct sk_buff *skb,
                        i += tx_ring->count;
                i--;
                buffer_info = &tx_ring->buffer_info[i];
-               e1000_put_txbuf(tx_ring, buffer_info);
+               e1000_put_txbuf(tx_ring, buffer_info, true);
        }
 
        return 0;
@@ -7411,7 +7415,7 @@ static void e1000_remove(struct pci_dev *pdev)
        if (adapter->flags & FLAG_HAS_HW_TIMESTAMP) {
                cancel_work_sync(&adapter->tx_hwtstamp_work);
                if (adapter->tx_hwtstamp_skb) {
-                       dev_kfree_skb_any(adapter->tx_hwtstamp_skb);
+                       dev_consume_skb_any(adapter->tx_hwtstamp_skb);
                        adapter->tx_hwtstamp_skb = NULL;
                }
        }
-- 
2.9.3