From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sergei Shtylyov Subject: Re: [net-next 13/20] i40evf: add new write-back mode Date: Sat, 6 Feb 2016 15:38:21 +0300 Message-ID: <56B5E93D.6080709@cogentembedded.com> References: <1454586551-35919-1-git-send-email-jeffrey.t.kirsher@intel.com> <1454586551-35919-14-git-send-email-jeffrey.t.kirsher@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Cc: Anjali Singhai Jain , netdev@vger.kernel.org, nhorman@redhat.com, sassmann@redhat.com, jogreene@redhat.com To: Jeff Kirsher , davem@davemloft.net Return-path: Received: from mail-lb0-f177.google.com ([209.85.217.177]:36217 "EHLO mail-lb0-f177.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752055AbcBFMi0 (ORCPT ); Sat, 6 Feb 2016 07:38:26 -0500 Received: by mail-lb0-f177.google.com with SMTP id dx2so62784269lbd.3 for ; Sat, 06 Feb 2016 04:38:25 -0800 (PST) In-Reply-To: <1454586551-35919-14-git-send-email-jeffrey.t.kirsher@intel.com> Sender: netdev-owner@vger.kernel.org List-ID: Hello. On 2/4/2016 2:49 PM, Jeff Kirsher wrote: > From: Anjali Singhai Jain > > Add write-back on interrupt throttle rate timer expiration support > for the i40evf driver, when running on X722 devices. > > Signed-off-by: Anjali Singhai Jain > Tested-by: Andrew Bowers > Signed-off-by: Jeff Kirsher [...] > diff --git a/drivers/net/ethernet/intel/i40evf/i40e_txrx.c b/drivers/net/ethernet/intel/i40evf/i40e_txrx.c > index 7a00657..7d663fb 100644 > --- a/drivers/net/ethernet/intel/i40evf/i40e_txrx.c > +++ b/drivers/net/ethernet/intel/i40evf/i40e_txrx.c > @@ -252,6 +252,22 @@ static bool i40e_clean_tx_irq(struct i40e_ring *tx_ring, int budget) > tx_ring->q_vector->tx.total_bytes += total_bytes; > tx_ring->q_vector->tx.total_packets += total_packets; > > + if (tx_ring->flags & I40E_TXR_FLAGS_WB_ON_ITR) { > + unsigned int j = 0; Pointless initializer, you override it on the next line. > + /* check to see if there are < 4 descriptors > + * waiting to be written back, then kick the hardware to force > + * them to be written back in case we stay in NAPI. > + * In this mode on X722 we do not enable Interrupt. > + */ > + j = i40evf_get_tx_pending(tx_ring); > + > + if (budget && > + ((j / (WB_STRIDE + 1)) == 0) && (j > 0) && > + !test_bit(__I40E_DOWN, &tx_ring->vsi->state) && > + (I40E_DESC_UNUSED(tx_ring) != tx_ring->count)) > + tx_ring->arm_wb = true; > + } > + > netdev_tx_completed_queue(netdev_get_tx_queue(tx_ring->netdev, > tx_ring->queue_index), > total_packets, total_bytes); [...] MBR, Sergei