From mboxrd@z Thu Jan  1 00:00:00 1970
From: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Subject: Re: [net-next 02/13] ixgbe: Fix ixgbe TX hangs with XDP_TX beyond
 queue limit
Date: Thu, 4 Oct 2018 12:08:49 +0300
Message-ID: <393d262e-ce4a-a786-a3bb-82ef73879d4c@cogentembedded.com>
References: <20181003202511.29684-1-jeffrey.t.kirsher@intel.com>
 <20181003202511.29684-3-jeffrey.t.kirsher@intel.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Transfer-Encoding: 7bit
Cc: Radoslaw Tyl <radoslawx.tyl@intel.com>, netdev@vger.kernel.org,
        nhorman@redhat.com, sassmann@redhat.com
To: Jeff Kirsher <jeffrey.t.kirsher@intel.com>, davem@davemloft.net
Return-path: <netdev-owner@vger.kernel.org>
Received: from mail-lf1-f67.google.com ([209.85.167.67]:35841 "EHLO
        mail-lf1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
        with ESMTP id S1726808AbeJDQBK (ORCPT
        <rfc822;netdev@vger.kernel.org>); Thu, 4 Oct 2018 12:01:10 -0400
Received: by mail-lf1-f67.google.com with SMTP id d4-v6so6236209lfa.3
        for <netdev@vger.kernel.org>; Thu, 04 Oct 2018 02:08:51 -0700 (PDT)
In-Reply-To: <20181003202511.29684-3-jeffrey.t.kirsher@intel.com>
Content-Language: en-US
Sender: netdev-owner@vger.kernel.org
List-ID: <netdev.vger.kernel.org>

Hello!

On 10/3/2018 11:25 PM, Jeff Kirsher wrote:

> From: Radoslaw Tyl <radoslawx.tyl@intel.com>
> 
> We have Tx hang when number Tx and XDP queues are more than 64.
                              ^ of

> In XDP always is MTQC == 0x0 (64TxQs). We need more space for Tx queues.
> 
> Signed-off-by: Radoslaw Tyl <radoslawx.tyl@intel.com>
> Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
> ---
>   drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 14 ++++++++++----
>   1 file changed, 10 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
> index 140e87a10ff5..ddc22557155b 100644
> --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
> +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
> @@ -3577,12 +3577,18 @@ static void ixgbe_setup_mtqc(struct ixgbe_adapter *adapter)
>   		else
>   			mtqc |= IXGBE_MTQC_64VF;
>   	} else {
> -		if (tcs > 4)
> +		if (tcs > 4) {
>   			mtqc = IXGBE_MTQC_RT_ENA | IXGBE_MTQC_8TC_8TQ;
> -		else if (tcs > 1)
> +		} else if (tcs > 1) {
>   			mtqc = IXGBE_MTQC_RT_ENA | IXGBE_MTQC_4TC_4TQ;
> -		else
> -			mtqc = IXGBE_MTQC_64Q_1PB;
> +		} else {
> +			u8 max_txq = adapter->num_tx_queues +
> +				adapter->num_xdp_queues;

    Empty line needed here, after declaration.

> +			if (max_txq > 63)
> +				mtqc = IXGBE_MTQC_RT_ENA | IXGBE_MTQC_4TC_4TQ;
> +			else
> +				mtqc = IXGBE_MTQC_64Q_1PB;
> +		}
>   	}
>   
>   	IXGBE_WRITE_REG(hw, IXGBE_MTQC, mtqc);

MBR, Sergei