net: stmmac: don't stop NAPI processing when dropping a packet
commit 07b3975352374c3f5ebb4a42ef0b253fe370542d upstream.
Currently, if we drop a packet, we exit from NAPI loop before the budget
is consumed. In some situations this will make the RX processing stall
e.g. when flood pinging the system with oversized packets, as the
errorneous packets are not dropped efficiently.
If we drop a packet, we should just continue to the next one as long as
the budget allows.
Signed-off-by: Aaro Koskinen <aaro.koskinen@nokia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
[acj: backport v4.9 -stable
-adjust context]
Signed-off-by: Aviraj CJ <acj@cisco.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index f184436..5ac48a5 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -2499,8 +2499,7 @@
*/
static int stmmac_rx(struct stmmac_priv *priv, int limit)
{
- unsigned int entry = priv->cur_rx;
- unsigned int next_entry;
+ unsigned int next_entry = priv->cur_rx;
unsigned int count = 0;
int coe = priv->hw->rx_csum;
@@ -2516,10 +2515,12 @@
priv->hw->desc->display_ring(rx_head, DMA_RX_SIZE, true);
}
while (count < limit) {
- int status;
+ int entry, status;
struct dma_desc *p;
struct dma_desc *np;
+ entry = next_entry;
+
if (priv->extend_desc)
p = (struct dma_desc *)(priv->dma_erx + entry);
else
@@ -2584,7 +2585,7 @@
priv->dev->name, frame_len,
priv->dma_buf_sz);
priv->dev->stats.rx_length_errors++;
- break;
+ continue;
}
/* ACS is set; GMAC core strips PAD/FCS for IEEE 802.3
@@ -2615,7 +2616,7 @@
dev_warn(priv->device,
"packet dropped\n");
priv->dev->stats.rx_dropped++;
- break;
+ continue;
}
dma_sync_single_for_cpu(priv->device,
@@ -2638,7 +2639,7 @@
pr_err("%s: Inconsistent Rx chain\n",
priv->dev->name);
priv->dev->stats.rx_dropped++;
- break;
+ continue;
}
prefetch(skb->data - NET_IP_ALIGN);
priv->rx_skbuff[entry] = NULL;
@@ -2672,7 +2673,6 @@
priv->dev->stats.rx_packets++;
priv->dev->stats.rx_bytes += frame_len;
}
- entry = next_entry;
}
stmmac_rx_refill(priv);