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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id F2382C433FE for ; Mon, 14 Mar 2022 14:59:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241525AbiCNPAJ (ORCPT ); Mon, 14 Mar 2022 11:00:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58356 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232280AbiCNPAI (ORCPT ); Mon, 14 Mar 2022 11:00:08 -0400 Received: from mail-ej1-x62b.google.com (mail-ej1-x62b.google.com [IPv6:2a00:1450:4864:20::62b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 280CA3C73B; Mon, 14 Mar 2022 07:58:58 -0700 (PDT) Received: by mail-ej1-x62b.google.com with SMTP id d10so34591186eje.10; Mon, 14 Mar 2022 07:58:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=OYV4LpH4D3agxsG3V7VyzstSf+lDz7EM5vQa2UkEP7w=; b=MOiHh0CsD3q+iNPxoPSXwT3iZzcB0ZcSFhKkrzBOMCkYSu7aKHbORB3emZtHnfBxYu v3dtH3qbNNm3Vi2nNIdfDrruOItemfOdVViSojC3sXZBM1YHKxbEtvfbb13NoFonpDil IMh6xGHEWuHI6yHyAYaLWJkI7K9IMXYWhHoYorlQAxEoMYom6ad0diEKR+HMICp5/tEX SP3kbCzP1qFzW5bV2gCgiYpimaqSn+c0SXq0O5OG3Pn4HJErrjdswwuRLYvwS0X1z5bL EajKTJDzTYBnw5lZVuhQzYCm25RotqH7PSMdw/AryMk6NHNJaUvcvC/z1eXwAlUn3UGi JdKw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=OYV4LpH4D3agxsG3V7VyzstSf+lDz7EM5vQa2UkEP7w=; b=swIuAx7KOFv/+ED1jBOiCK8IO/0Mf0xjOveXMJGo1CdMBm2ZXyyFGUAJ5XYXLc+nrf kBnU6UC4dA8pKFYAqTCA2jliXZE4dB2eHBH3j7Uch3guNtkPJ9jtjmo1VdcpkkRrNK86 KsExMbWWI7unzS8XgRftVmu0Zbf0ERnywLaSGut1TuaNxfEeRCywaUVATq7gajIlILFI 35kkgI8f9SGlNhyg5OzTD+nPTpPa67OllKj3oMB0xkvrGGW+sb79InwqR9mLCzwS4Yrp /vbmMPf+8adp8BSYNn/AsvEaqDXIS/7G6DtPfeu7jGldXeTJG1eTfJA9+z7N7QyjSJ01 37cQ== X-Gm-Message-State: AOAM531kHk+LSLgLco9oXACCrWb+GJhCwHgCfZYbKasGmQmsZHoMiuyS wvzW81DhCFDB2KQ7iMSC+AU= X-Google-Smtp-Source: ABdhPJwEXXJr7N8/UGnBPerXHkgdsTRUxrmYmjgrx1ZKylhRSvtZpmHi617uiUE4yKGd6/6FaDkQcw== X-Received: by 2002:a17:907:2cc6:b0:6db:7e92:e36 with SMTP id hg6-20020a1709072cc600b006db7e920e36mr18090693ejc.329.1647269936492; Mon, 14 Mar 2022 07:58:56 -0700 (PDT) Received: from skbuf ([188.25.231.156]) by smtp.gmail.com with ESMTPSA id a1-20020aa7d901000000b00416217c99bcsm8157560edr.65.2022.03.14.07.58.55 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 14 Mar 2022 07:58:56 -0700 (PDT) Date: Mon, 14 Mar 2022 16:58:54 +0200 From: Vladimir Oltean To: Tobias Waldekranz Cc: davem@davemloft.net, kuba@kernel.org, Andrew Lunn , Vivien Didelot , Florian Fainelli , Jiri Pirko , Ivan Vecera , Roopa Prabhu , Nikolay Aleksandrov , Russell King , Ido Schimmel , Petr Machata , Cooper Lees , Matt Johnston , linux-kernel@vger.kernel.org, netdev@vger.kernel.org, bridge@lists.linux-foundation.org Subject: Re: [PATCH v3 net-next 03/14] net: bridge: mst: Support setting and reporting MST port states Message-ID: <20220314145854.shtnvetounjfnu4e@skbuf> References: <20220314095231.3486931-1-tobias@waldekranz.com> <20220314095231.3486931-4-tobias@waldekranz.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220314095231.3486931-4-tobias@waldekranz.com> Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Mon, Mar 14, 2022 at 10:52:20AM +0100, Tobias Waldekranz wrote: > +int br_mst_fill_info(struct sk_buff *skb, struct net_bridge_vlan_group *vg) > +{ > + struct net_bridge_vlan *v; > + struct nlattr *nest; > + unsigned long *seen; > + int err = 0; > + > + seen = bitmap_zalloc(VLAN_N_VID, 0); I see there is precedent in the bridge driver for using dynamic allocation as opposed to on-stack declaration using DECLARE_BITMAP(). I imagine this isn't just to be "heapsters", but why? I don't have a very good sense of how much on-stack memory is too much (a lot probably depends on the expected depth of the call stack too, and here it doesn't appear to be too deep), but I see that mlxsw_sp_bridge_vxlan_vlan_is_valid() has a DECLARE_BITMAP(vlans, VLAN_N_VID) too. The comment applies for callers of br_mst_get_info() too. > + if (!seen) > + return -ENOMEM; > + > + list_for_each_entry(v, &vg->vlan_list, vlist) { > + if (test_bit(v->brvlan->msti, seen)) > + continue; > + > + nest = nla_nest_start_noflag(skb, IFLA_BRIDGE_MST_ENTRY); > + if (!nest || > + nla_put_u16(skb, IFLA_BRIDGE_MST_ENTRY_MSTI, v->brvlan->msti) || > + nla_put_u8(skb, IFLA_BRIDGE_MST_ENTRY_STATE, v->state)) { > + err = -EMSGSIZE; > + break; > + } > + nla_nest_end(skb, nest); > + > + set_bit(v->brvlan->msti, seen); > + } > + > + kfree(seen); > + return err; > +}