net: systemport: log RX buffer allocation and RX/TX DMA failures

To help troubleshoot heavy memory pressure conditions, add a bunch of
statistics counter to log RX buffer allocation and RX/TX DMA mapping
failures. These are reported like any other counters through the ethtool
stats interface.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/broadcom/bcmsysport.c b/drivers/net/ethernet/broadcom/bcmsysport.c
index 3cb2411..c1d2559 100644 (file)
--- a/drivers/net/ethernet/broadcom/bcmsysport.c
+++ b/drivers/net/ethernet/broadcom/bcmsysport.c
@@ -274,6 +274,9 @@ static const struct bcm_sysport_stats bcm_sysport_gstrings_stats[] = {
        /* RBUF misc statistics */
        STAT_RBUF("rbuf_ovflow_cnt", mib.rbuf_ovflow_cnt, RBUF_OVFL_DISC_CNTR),
        STAT_RBUF("rbuf_err_cnt", mib.rbuf_err_cnt, RBUF_ERR_PKT_CNTR),
+       STAT_MIB_RX("alloc_rx_buff_failed", mib.alloc_rx_buff_failed),
+       STAT_MIB_RX("rx_dma_failed", mib.rx_dma_failed),
+       STAT_MIB_TX("tx_dma_failed", mib.tx_dma_failed),
 };
 
 #define BCM_SYSPORT_STATS_LEN  ARRAY_SIZE(bcm_sysport_gstrings_stats)
@@ -477,6 +480,7 @@ static int bcm_sysport_rx_refill(struct bcm_sysport_priv *priv,
                                 RX_BUF_LENGTH, DMA_FROM_DEVICE);
        ret = dma_mapping_error(kdev, mapping);
        if (ret) {
+               priv->mib.rx_dma_failed++;
                bcm_sysport_free_cb(cb);
                netif_err(priv, rx_err, ndev, "DMA mapping failure\n");
                return ret;
@@ -526,6 +530,7 @@ static unsigned int bcm_sysport_desc_rx(struct bcm_sysport_priv *priv,
        unsigned int p_index;
        u16 len, status;
        struct bcm_rsb *rsb;
+       int ret;
 
        /* Determine how much we should process since last call */
        p_index = rdma_readl(priv, RDMA_PROD_INDEX);
@@ -620,7 +625,9 @@ static unsigned int bcm_sysport_desc_rx(struct bcm_sysport_priv *priv,
 
                napi_gro_receive(&priv->napi, skb);
 refill:
-               bcm_sysport_rx_refill(priv, cb);
+               ret = bcm_sysport_rx_refill(priv, cb);
+               if (ret)
+                       priv->mib.alloc_rx_buff_failed++;
        }
 
        return processed;
@@ -973,6 +980,7 @@ static netdev_tx_t bcm_sysport_xmit(struct sk_buff *skb,
 
        mapping = dma_map_single(kdev, skb->data, skb_len, DMA_TO_DEVICE);
        if (dma_mapping_error(kdev, mapping)) {
+               priv->mib.tx_dma_failed++;
                netif_err(priv, tx_err, dev, "DMA map failed at %p (len=%d)\n",
                          skb->data, skb_len);
                ret = NETDEV_TX_OK;

diff --git a/drivers/net/ethernet/broadcom/bcmsysport.h b/drivers/net/ethernet/broadcom/bcmsysport.h
index b08dab8..fc19417 100644 (file)
--- a/drivers/net/ethernet/broadcom/bcmsysport.h
+++ b/drivers/net/ethernet/broadcom/bcmsysport.h
@@ -557,6 +557,9 @@ struct bcm_sysport_mib {
        u32 rxchk_other_pkt_disc;
        u32 rbuf_ovflow_cnt;
        u32 rbuf_err_cnt;
+       u32 alloc_rx_buff_failed;
+       u32 rx_dma_failed;
+       u32 tx_dma_failed;
 };
 
 /* HW maintains a large list of counters */