From 41b976414c88016e2c9d9b2f6667ee67a998d388 Mon Sep 17 00:00:00 2001 From: David Woodhouse Date: Wed, 23 Sep 2015 09:45:31 +0100 Subject: [PATCH] 8139cp: Dump contents of descriptor ring on TX timeout We are seeing unexplained TX timeouts under heavy load. Let's try to get a better idea of what's going on. Signed-off-by: David Woodhouse Signed-off-by: David S. Miller --- drivers/net/ethernet/realtek/8139cp.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/realtek/8139cp.c b/drivers/net/ethernet/realtek/8139cp.c index ec6bd86..686334f 100644 --- a/drivers/net/ethernet/realtek/8139cp.c +++ b/drivers/net/ethernet/realtek/8139cp.c @@ -157,6 +157,7 @@ enum { NWayAdvert = 0x66, /* MII ADVERTISE */ NWayLPAR = 0x68, /* MII LPA */ NWayExpansion = 0x6A, /* MII Expansion */ + TxDmaOkLowDesc = 0x82, /* Low 16 bit address of a Tx descriptor. */ Config5 = 0xD8, /* Config5 */ TxPoll = 0xD9, /* Tell chip to check Tx descriptors for work */ RxMaxSize = 0xDA, /* Max size of an Rx packet (8169 only) */ @@ -1234,7 +1235,7 @@ static void cp_tx_timeout(struct net_device *dev) { struct cp_private *cp = netdev_priv(dev); unsigned long flags; - int rc; + int rc, i; netdev_warn(dev, "Transmit timeout, status %2x %4x %4x %4x\n", cpr8(Cmd), cpr16(CpCmd), @@ -1242,6 +1243,17 @@ static void cp_tx_timeout(struct net_device *dev) spin_lock_irqsave(&cp->lock, flags); + netif_dbg(cp, tx_err, cp->dev, "TX ring head %d tail %d desc %x\n", + cp->tx_head, cp->tx_tail, cpr16(TxDmaOkLowDesc)); + for (i = 0; i < CP_TX_RING_SIZE; i++) { + netif_dbg(cp, tx_err, cp->dev, + "TX slot %d @%p: %08x (%08x) %08x %llx %p\n", + i, &cp->tx_ring[i], le32_to_cpu(cp->tx_ring[i].opts1), + cp->tx_opts[i], le32_to_cpu(cp->tx_ring[i].opts2), + le64_to_cpu(cp->tx_ring[i].addr), + cp->tx_skb[i]); + } + cp_stop_hw(cp); cp_clean_rings(cp); rc = cp_init_rings(cp); -- 2.7.4