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=-7.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 B1DE5C4361B for ; Thu, 17 Dec 2020 18:32:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 85BF0238E8 for ; Thu, 17 Dec 2020 18:32:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730222AbgLQScf (ORCPT ); Thu, 17 Dec 2020 13:32:35 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45702 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728704AbgLQScf (ORCPT ); Thu, 17 Dec 2020 13:32:35 -0500 Received: from mail-ej1-x629.google.com (mail-ej1-x629.google.com [IPv6:2a00:1450:4864:20::629]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 840AAC061794 for ; Thu, 17 Dec 2020 10:31:54 -0800 (PST) Received: by mail-ej1-x629.google.com with SMTP id j22so21350059eja.13 for ; Thu, 17 Dec 2020 10:31:54 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=PaQLFCPDXYdRBDF0cqZO2lJPciGJZchQccbI7HdVSMU=; b=mFlsIgpstAtaXooJSG7Kd4fb1ctinOQ7VzQPp1I4l11uRT6AUmApLJmpirHM5tprWL 2k224z19mqdGbgpx2tPwUZjSS0pH0pg2JzeFGvflV30iXSJSk7toUiD5MiSwEM0UluX+ IvrGkspnS60FCN5sWfCFQ4BWTi2/h+WRbzkNJrjHIwceTtUZIv4I2trnN1fKiBUaTCvz d9Hd/AyraveG01rA76vxtTV8Orwkw78bEfYHiyz0mHr65W1lgEVwcIFRAeRkrwjuMiIb mCY1B+Cona9zaMsmx/07xzfLBEY5vFqJMKQKA8GPhP6hTR6IwJT+4b+CCXXf+lBZm6tj Ry4A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=PaQLFCPDXYdRBDF0cqZO2lJPciGJZchQccbI7HdVSMU=; b=TZfivmSiUlq6zkGxPt3I6m1LlX/0pbaHG9ijShud2LLxQWPbarrKEiy+byq+G3wj3c qQFYculTGKnbXvWcxd/6+eUWG4xSn0UxP/1T77qZYIQ2U2BTeGZtq2dNIq+Mqw/6VpuW UySsSYyi8zsw0Mb4keE5bp/lF5s2ARoQeXOfVU/ERuSRwZXa6JX4ELCb3YMMROqsoX2K 98wt47URXdSrPgvuSf36UHsd6ptPwRE7BwBuE9FdBPvOWC7hY6xcVatWYvRSqxqjN0mn IZ90N1CEehaOrg5T6MPAoEp5AIXNmGdFtfwyN/eoKAqOYw4+S0rB5eFsCb58YvcWFKcw Bv8A== X-Gm-Message-State: AOAM530feKvBGQmrFRvUwDmaq1A2sU2vOdetucX9VS7wyQ1JvI2fpBJs y24wfXF5YERnsSKRkTge2bg= X-Google-Smtp-Source: ABdhPJzFH3Rqajs7CyBf51+438YGtQv7F9xE3XQ7SkWk2NPRzJ2btx7GnJmCOor4kXTiFcjA+gwS+w== X-Received: by 2002:a17:907:2d0f:: with SMTP id gs15mr276804ejc.455.1608229913179; Thu, 17 Dec 2020 10:31:53 -0800 (PST) Received: from skbuf ([188.25.2.120]) by smtp.gmail.com with ESMTPSA id t12sm23858650edy.49.2020.12.17.10.31.51 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 17 Dec 2020 10:31:51 -0800 (PST) Date: Thu, 17 Dec 2020 20:31:50 +0200 From: Vladimir Oltean To: Tobias Waldekranz Cc: davem@davemloft.net, kuba@kernel.org, andrew@lunn.ch, vivien.didelot@gmail.com, f.fainelli@gmail.com, j.vosburgh@gmail.com, vfalico@gmail.com, andy@greyhouse.net, netdev@vger.kernel.org Subject: Re: [PATCH v4 net-next 3/5] net: dsa: Link aggregation support Message-ID: <20201217183150.utyeibdh7too5rmb@skbuf> References: <20201216160056.27526-1-tobias@waldekranz.com> <20201216160056.27526-4-tobias@waldekranz.com> <20201216184427.amplixitum6x2zui@skbuf> <87k0thbjhl.fsf@waldekranz.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87k0thbjhl.fsf@waldekranz.com> Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Wed, Dec 16, 2020 at 09:09:58PM +0100, Tobias Waldekranz wrote: > On Wed, Dec 16, 2020 at 20:44, Vladimir Oltean wrote: > > On Wed, Dec 16, 2020 at 05:00:54PM +0100, Tobias Waldekranz wrote: > >> diff --git a/net/dsa/dsa2.c b/net/dsa/dsa2.c > >> index 183003e45762..deee4c0ecb31 100644 > >> --- a/net/dsa/dsa2.c > >> +++ b/net/dsa/dsa2.c > >> @@ -21,6 +21,46 @@ > >> static DEFINE_MUTEX(dsa2_mutex); > >> LIST_HEAD(dsa_tree_list); > >> > >> +void dsa_lag_map(struct dsa_switch_tree *dst, struct net_device *lag) > > > > Maybe a small comment here and in dsa_lag_unmap, describing what they're > > for? They look a bit bland. Just a few words about the linear array will > > suffice. > > Not sure I understand why these two are "bland" whereas dsa_switch_find > just below it is not. But sure, I will add a comment. You want a block > comment before each function? What I meant is that if you're just a casual reader carrying on with your day and you see a function called dsa_switch_find, you have a vague idea what it does just by reading the headline - it finds a DSA switch. Whereas dsa_lag_map, I don't know, just doesn't speak to me, it's a very uneventful name with a very uneventful implementation. If we hadn't had the long discussion in the previous version about the linear array, I would have honestly had to ask you what's the purpose of "mapping" and "unmapping" a LAG. So I expect many of the readers ask themselves the same thing, especially since the comments say that some drivers don't use it. I guess this would look more dynamic for me: /* Helpers to add and remove a LAG net_device from this switch tree's * mapping towards a linear ID. These will do nothing for drivers which * don't populate ds->num_lag_ids, and therefore don't need the mapping. */ void dsa_lag_map(struct dsa_switch_tree *dst, struct net_device *lag) { unsigned int id; if (dsa_lag_id(dst, lag) >= 0) /* Already mapped */ return; for (id = 0; id < dst->lags_len; id++) { if (!dsa_lag_dev(dst, id)) { dst->lags[id] = lag; return; } } /* No IDs left, which is OK. Calling dsa_lag_id will return an * error when this device joins a LAG. The driver can then * return -EOPNOTSUPP back to DSA, which will fall back to a * software LAG. */ } void dsa_lag_unmap(struct dsa_switch_tree *dst, struct net_device *lag) { struct dsa_port *dp; unsigned int id; dsa_lag_foreach_port(dp, dst, lag) /* There are remaining users of this mapping */ return; dsa_lags_foreach_id(id, dst) { if (dsa_lag_dev(dst, id) == lag) { dst->lags[id] = NULL; break; } } }