From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4B719C3815B for ; Mon, 20 Apr 2020 12:39:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 277242070B for ; Mon, 20 Apr 2020 12:39:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726825AbgDTMjW (ORCPT ); Mon, 20 Apr 2020 08:39:22 -0400 Received: from correo.us.es ([193.147.175.20]:54906 "EHLO mail.us.es" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726562AbgDTMjT (ORCPT ); Mon, 20 Apr 2020 08:39:19 -0400 Received: from antivirus1-rhel7.int (unknown [192.168.2.11]) by mail.us.es (Postfix) with ESMTP id 1CBEEFB454 for ; Mon, 20 Apr 2020 14:39:18 +0200 (CEST) Received: from antivirus1-rhel7.int (localhost [127.0.0.1]) by antivirus1-rhel7.int (Postfix) with ESMTP id 0D8EDDA736 for ; Mon, 20 Apr 2020 14:39:18 +0200 (CEST) Received: by antivirus1-rhel7.int (Postfix, from userid 99) id E97D9FA52A; Mon, 20 Apr 2020 14:39:17 +0200 (CEST) Received: from antivirus1-rhel7.int (localhost [127.0.0.1]) by antivirus1-rhel7.int (Postfix) with ESMTP id 1315A100A44; Mon, 20 Apr 2020 14:39:16 +0200 (CEST) Received: from 192.168.1.97 (192.168.1.97) by antivirus1-rhel7.int (F-Secure/fsigk_smtp/550/antivirus1-rhel7.int); Mon, 20 Apr 2020 14:39:16 +0200 (CEST) X-Virus-Status: clean(F-Secure/fsigk_smtp/550/antivirus1-rhel7.int) Received: from us.es (unknown [90.77.255.23]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) (Authenticated sender: 1984lsi) by entrada.int (Postfix) with ESMTPSA id E99E842EF42B; Mon, 20 Apr 2020 14:39:15 +0200 (CEST) Date: Mon, 20 Apr 2020 14:39:15 +0200 X-SMTPAUTHUS: auth mail.us.es From: Pablo Neira Ayuso To: Edward Cree Cc: Jiri Pirko , netfilter-devel@vger.kernel.org, davem@davemloft.net, netdev@vger.kernel.org, kuba@kernel.org Subject: Re: [PATCH net] net: flow_offload: skip hw stats check for FLOW_ACTION_HW_STATS_DISABLED Message-ID: <20200420123915.nrqancwjb7226l7e@salvia> References: <20200419115338.659487-1-pablo@netfilter.org> <20200420080200.GA6581@nanopsycho.orion> <20200420090505.pr6wsunozfh7afaj@salvia> <20200420091302.GB6581@nanopsycho.orion> <20200420100341.6qehcgz66wq4ysax@salvia> <20200420115210.GE6581@nanopsycho.orion> <3980eea4-18d8-5e62-2d6d-fce0a7e7ed4c@solarflare.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <3980eea4-18d8-5e62-2d6d-fce0a7e7ed4c@solarflare.com> User-Agent: NeoMutt/20170113 (1.7.2) X-Virus-Scanned: ClamAV using ClamSMTP Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Mon, Apr 20, 2020 at 01:28:22PM +0100, Edward Cree wrote: > On 20/04/2020 12:52, Jiri Pirko wrote: > > However for TC, when user specifies "HW_STATS_DISABLED", the driver > > should not do stats. > > What should a driver do if the user specifies DISABLED, but the stats >  are still needed for internal bookkeeping (e.g. to prod an ARP entry >  that's in use for encapsulation offload, so that it doesn't get >  expired out of the cache)?  Enable the stats on the HW anyway but >  not report them to FLOW_CLS_STATS?  Or return an error? My interpretation is that HW_STATS_DISABLED means that the front-end does not care / does not need counters. The driver can still allocate them if needed. So the enum flow_action_hw_stats flags represent what the front-end requires.