RE: [Intel-wired-lan] [PATCH net-next v3] e1000e: Be drop monitor friendly

[Brown, Aaron F]

> From: Intel-wired-lan [mailto:intel-wired-lan-boun...@osuosl.org] On Behalf
> Of Florian Fainelli
> Sent: Friday, August 25, 2017 6:14 PM
> To: netdev@vger.kernel.org
> Cc: eduma...@gmail.com; Florian Fainelli ; open list
> ; moderated list:INTEL ETHERNET DRIVERS
> ; da...@davemloft.net
> Subject: [Intel-wired-lan] [PATCH net-next v3] e1000e: Be drop monitor
> friendly
> 
> 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 
> ---
> 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(-)

Tested-by: Aaron Brown 

Re: [Intel-wired-lan] [PATCH net-next v3] e1000e: Be drop monitor friendly

[Neftin, Sasha]

On 8/26/2017 04:14, Florian Fainelli wrote:

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 
---
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;
}
}


i am ok with this patch