From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Graf Subject: Re: [patch net-next 1/4] netdevice: add SW statistics ndo Date: Tue, 17 May 2016 10:39:08 +0200 Message-ID: <20160517083908.GA13823@pox.localdomain> References: <1463053730-14991-1-git-send-email-jiri@resnulli.us> <1463053730-14991-2-git-send-email-jiri@resnulli.us> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: netdev@vger.kernel.org, davem@davemloft.net, nogahf@mellanox.com, idosch@mellanox.com, eladr@mellanox.com, yotamg@mellanox.com, ogerlitz@mellanox.com, roopa@cumulusnetworks.com, nikolay@cumulusnetworks.com, linville@tuxdriver.com, gospo@cumulusnetworks.com, sfeldma@gmail.com, sd@queasysnail.net, eranbe@mellanox.com, ast@plumgrid.com, edumazet@google.com, hannes@stressinduktion.org To: Jiri Pirko Return-path: Received: from mail-wm0-f45.google.com ([74.125.82.45]:37744 "EHLO mail-wm0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750799AbcEQIjM (ORCPT ); Tue, 17 May 2016 04:39:12 -0400 Received: by mail-wm0-f45.google.com with SMTP id a17so17717195wme.0 for ; Tue, 17 May 2016 01:39:11 -0700 (PDT) Content-Disposition: inline In-Reply-To: <1463053730-14991-2-git-send-email-jiri@resnulli.us> Sender: netdev-owner@vger.kernel.org List-ID: On 05/12/16 at 01:48pm, Jiri Pirko wrote: > diff --git a/net/core/dev.c b/net/core/dev.c > index 12436d1..a69e418 100644 > --- a/net/core/dev.c > +++ b/net/core/dev.c > @@ -7376,6 +7376,8 @@ EXPORT_SYMBOL(netdev_stats_to_stats64); > * The device driver may provide its own method by setting > * dev->netdev_ops->get_stats64 or dev->netdev_ops->get_stats; > * otherwise the internal statistics structure is used. > + * If device supports both HW & SW statistics - this function should > + * return the HW statistics. > */ > struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev, > struct rtnl_link_stats64 *storage) Can we clarify in a comment that given HW stats are available whether this would continue to account for something like a memory allocation failure through tx_dropped (for drivers which do skb_realloc_headroom() in xmit) or tx_busy for when the ring is busy? HW would never see such failures Is the expectation that dev_get_stats() continues to include these software failures?