pch_gbe: Fixed the issue on which a network freezes

The pch_gbe driver has an issue which a network stops,
when receiving traffic is high.
In the case, The link down and up are necessary to return a network.

This patch fixed this issue.

Signed-off-by: Toshiharu Okada <toshiharu-linux@dsn.okisemi.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/pch_gbe/pch_gbe_main.c b/drivers/net/pch_gbe/pch_gbe_main.c
index 5474189..b8b4ba2 100644 (file)
--- a/drivers/net/pch_gbe/pch_gbe_main.c
+++ b/drivers/net/pch_gbe/pch_gbe_main.c
@@ -1199,6 +1199,8 @@ static irqreturn_t pch_gbe_intr(int irq, void *data)
                        iowrite32((int_en & ~PCH_GBE_INT_RX_FIFO_ERR),
                                  &hw->reg->INT_EN);
                        pch_gbe_stop_receive(adapter);
+                       int_st |= ioread32(&hw->reg->INT_ST);
+                       int_st = int_st & ioread32(&hw->reg->INT_EN);
                }
        if (int_st & PCH_GBE_INT_RX_DMA_ERR)
                adapter->stats.intr_rx_dma_err_count++;
@@ -1218,14 +1220,11 @@ static irqreturn_t pch_gbe_intr(int irq, void *data)
                        /* Set Pause packet */
                        pch_gbe_mac_set_pause_packet(hw);
                }
-               if ((int_en & (PCH_GBE_INT_RX_DMA_CMPLT | PCH_GBE_INT_TX_CMPLT))
-                   == 0) {
-                       return IRQ_HANDLED;
-               }
        }
 
        /* When request status is Receive interruption */
-       if ((int_st & (PCH_GBE_INT_RX_DMA_CMPLT | PCH_GBE_INT_TX_CMPLT))) {
+       if ((int_st & (PCH_GBE_INT_RX_DMA_CMPLT | PCH_GBE_INT_TX_CMPLT)) ||
+           (adapter->rx_stop_flag == true)) {
                if (likely(napi_schedule_prep(&adapter->napi))) {
                        /* Enable only Rx Descriptor empty */
                        atomic_inc(&adapter->irq_sem);
@@ -1385,7 +1384,7 @@ pch_gbe_clean_tx(struct pch_gbe_adapter *adapter,
        struct sk_buff *skb;
        unsigned int i;
        unsigned int cleaned_count = 0;
-       bool cleaned = false;
+       bool cleaned = true;
 
        pr_debug("next_to_clean : %d\n", tx_ring->next_to_clean);
 
@@ -1396,7 +1395,6 @@ pch_gbe_clean_tx(struct pch_gbe_adapter *adapter,
 
        while ((tx_desc->gbec_status & DSC_INIT16) == 0x0000) {
                pr_debug("gbec_status:0x%04x\n", tx_desc->gbec_status);
-               cleaned = true;
                buffer_info = &tx_ring->buffer_info[i];
                skb = buffer_info->skb;
 
@@ -1439,8 +1437,10 @@ pch_gbe_clean_tx(struct pch_gbe_adapter *adapter,
                tx_desc = PCH_GBE_TX_DESC(*tx_ring, i);
 
                /* weight of a sort for tx, to avoid endless transmit cleanup */
-               if (cleaned_count++ == PCH_GBE_TX_WEIGHT)
+               if (cleaned_count++ == PCH_GBE_TX_WEIGHT) {
+                       cleaned = false;
                        break;
+               }
        }
        pr_debug("called pch_gbe_unmap_and_free_tx_resource() %d count\n",
                 cleaned_count);
@@ -2168,7 +2168,6 @@ static int pch_gbe_napi_poll(struct napi_struct *napi, int budget)
 {
        struct pch_gbe_adapter *adapter =
            container_of(napi, struct pch_gbe_adapter, napi);
-       struct net_device *netdev = adapter->netdev;
        int work_done = 0;
        bool poll_end_flag = false;
        bool cleaned = false;
@@ -2176,33 +2175,32 @@ static int pch_gbe_napi_poll(struct napi_struct *napi, int budget)
 
        pr_debug("budget : %d\n", budget);
 
-       /* Keep link state information with original netdev */
-       if (!netif_carrier_ok(netdev)) {
+       pch_gbe_clean_rx(adapter, adapter->rx_ring, &work_done, budget);
+       cleaned = pch_gbe_clean_tx(adapter, adapter->tx_ring);
+
+       if (!cleaned)
+               work_done = budget;
+       /* If no Tx and not enough Rx work done,
+        * exit the polling mode
+        */
+       if (work_done < budget)
                poll_end_flag = true;
-       } else {
-               pch_gbe_clean_rx(adapter, adapter->rx_ring, &work_done, budget);
+
+       if (poll_end_flag) {
+               napi_complete(napi);
+               if (adapter->rx_stop_flag) {
+                       adapter->rx_stop_flag = false;
+                       pch_gbe_start_receive(&adapter->hw);
+               }
+               pch_gbe_irq_enable(adapter);
+       } else
                if (adapter->rx_stop_flag) {
                        adapter->rx_stop_flag = false;
                        pch_gbe_start_receive(&adapter->hw);
                        int_en = ioread32(&adapter->hw.reg->INT_EN);
                        iowrite32((int_en | PCH_GBE_INT_RX_FIFO_ERR),
-                                       &adapter->hw.reg->INT_EN);
+                               &adapter->hw.reg->INT_EN);
                }
-               cleaned = pch_gbe_clean_tx(adapter, adapter->tx_ring);
-
-               if (cleaned)
-                       work_done = budget;
-               /* If no Tx and not enough Rx work done,
-                * exit the polling mode
-                */
-               if (work_done < budget)
-                       poll_end_flag = true;
-       }
-
-       if (poll_end_flag) {
-               napi_complete(napi);
-               pch_gbe_irq_enable(adapter);
-       }
 
        pr_debug("poll_end_flag : %d  work_done : %d  budget : %d\n",
                 poll_end_flag, work_done, budget);