From 344756f6e36b056ed361eedbd68244b108bdb1c6 Mon Sep 17 00:00:00 2001 From: Russell King Date: Tue, 8 Jul 2014 13:01:59 +0100 Subject: [PATCH] net: fec: add support for dumping transmit ring on timeout When we timeout on transmit, it would be useful to dump the transmit ring, so we can see the ring state. This can be helpful to diagnose the cause of transmit timeouts. Acked-by: Fugang Duan Signed-off-by: Russell King Signed-off-by: David S. Miller --- drivers/net/ethernet/freescale/fec_main.c | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c index c6b1bf797a39..09fcdc768931 100644 --- a/drivers/net/ethernet/freescale/fec_main.c +++ b/drivers/net/ethernet/freescale/fec_main.c @@ -320,6 +320,27 @@ static void *swap_buffer(void *bufaddr, int len) return bufaddr; } +static void fec_dump(struct net_device *ndev) +{ + struct fec_enet_private *fep = netdev_priv(ndev); + struct bufdesc *bdp = fep->tx_bd_base; + unsigned int index = 0; + + netdev_info(ndev, "TX ring dump\n"); + pr_info("Nr SC addr len SKB\n"); + + do { + pr_info("%3u %c%c 0x%04x 0x%08lx %4u %p\n", + index, + bdp == fep->cur_tx ? 'S' : ' ', + bdp == fep->dirty_tx ? 'H' : ' ', + bdp->cbd_sc, bdp->cbd_bufaddr, bdp->cbd_datlen, + fep->tx_skbuff[index]); + bdp = fec_enet_get_nextdesc(bdp, fep); + index++; + } while (bdp != fep->tx_bd_base); +} + static inline bool is_ipv4_pkt(struct sk_buff *skb) { return skb->protocol == htons(ETH_P_IP) && ip_hdr(skb)->version == 4; @@ -1018,6 +1039,8 @@ fec_timeout(struct net_device *ndev) { struct fec_enet_private *fep = netdev_priv(ndev); + fec_dump(ndev); + ndev->stats.tx_errors++; schedule_work(&fep->tx_timeout_work); -- 2.20.1