Subject: Re: ixgbe question

From: Eric Dumazet <[email-masked]>
Date: Tue, 24 Nov 2009 10:55:50 +0100

Peter P Waskiewicz Jr a écrit :

> You might have this elsewhere, but it sounds like you're connecting back
> to back with another 82599 NIC.  Our optics in that NIC are dual-rate,
> and the software mechanism that tries to "autoneg" link speed gets out
> of sync easily in back-to-back setups.
> 
> If it's really annoying, and you're willing to run with a local patch to
> disable the autotry mechanism, try this:
> 
> diff --git a/drivers/net/ixgbe/ixgbe_main.c
> b/drivers/net/ixgbe/ixgbe_main.c
> index a5036f7..62c0915 100644
> --- a/drivers/net/ixgbe/ixgbe_main.c
> +++ b/drivers/net/ixgbe/ixgbe_main.c
> @@ -4670,6 +4670,10 @@ static void ixgbe_multispeed_fiber_task(struct
> work_struct *work)
>         autoneg = hw->phy.autoneg_advertised;
>         if ((!autoneg) && (hw->mac.ops.get_link_capabilities))
>                 hw->mac.ops.get_link_capabilities(hw, &autoneg,
> &negotiation);
> +
> +       /* force 10G only */
> +       autoneg = IXGBE_LINK_SPEED_10GB_FULL;
> +
>         if (hw->mac.ops.setup_link)
>                 hw->mac.ops.setup_link(hw, autoneg, negotiation, true);
>         adapter->flags |= IXGBE_FLAG_NEED_LINK_UPDATE;

Thanks ! This did the trick :)

If I am not mistaken, number of TX queues should be capped by number of possible cpus ?

Its currently a fixed 128 value, allocating 128*128 = 16384 bytes,
and polluting "tc -s -d class show dev fiber0" output.

[PATCH net-next-2.6] ixgbe: Do not allocate too many netdev txqueues

Instead of allocating 128 struct netdev_queue per device, use the minimum
value between 128 and number of possible cpus, to reduce ram usage and
"tc -s -d class show dev ..." output

diff --git a/drivers/net/ixgbe/ixgbe_main.c b/drivers/net/ixgbe/ixgbe_main.c
index ebcec30..ec2508d 100644
--- a/drivers/net/ixgbe/ixgbe_main.c
+++ b/drivers/net/ixgbe/ixgbe_main.c
@@ -5582,7 +5583,10 @@ static int __devinit ixgbe_probe(struct pci_dev *pdev,
 	pci_set_master(pdev);
 	pci_save_state(pdev);
 
-	netdev = alloc_etherdev_mq(sizeof(struct ixgbe_adapter), MAX_TX_QUEUES);
+	netdev = alloc_etherdev_mq(sizeof(struct ixgbe_adapter),
+				   min_t(unsigned int,
+					 MAX_TX_QUEUES,
+					 num_possible_cpus()));
 	if (!netdev) {
 		err = -ENOMEM;
 		goto err_alloc_etherdev;