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 smtp3.osuosl.org (smtp3.osuosl.org [140.211.166.136]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 3AA4010706E4 for ; Sat, 14 Mar 2026 16:35:26 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp3.osuosl.org (Postfix) with ESMTP id F0016607E5; Sat, 14 Mar 2026 16:35:25 +0000 (UTC) X-Virus-Scanned: amavis at osuosl.org Received: from smtp3.osuosl.org ([127.0.0.1]) by localhost (smtp3.osuosl.org [127.0.0.1]) (amavis, port 10024) with ESMTP id KMHBNCS6NhWj; Sat, 14 Mar 2026 16:35:25 +0000 (UTC) X-Comment: SPF check N/A for local connections - client-ip=140.211.166.142; helo=lists1.osuosl.org; envelope-from=intel-wired-lan-bounces@osuosl.org; receiver= DKIM-Filter: OpenDKIM Filter v2.11.0 smtp3.osuosl.org 71C79607F7 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=osuosl.org; s=default; t=1773506125; bh=L/eakVxCmU6z4MfVX/Tn/gRdChsPQgl7sUT4bvaSUng=; h=Date:From:To:Cc:In-Reply-To:References:Subject:List-Id: List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe: From; b=zHpJmiooHL0h3nJp9uJTkd/y1itASvE0F4rnwRYwl3qu7Sip2Dccjr60aQle/Ui26 NlT1HNUCvpHKNG728t8MMaUDxHs4cqKkR/x/2lhGrcroAZGsuhV6mp16s04q5vhFvG s/moTvtAdM+seED9u8y/hcXGzlSapmju89aYnOYoW2J0eWMDRqelF+tnKWDYlTxz6O POabVvy76UW2JD81o4muxcyNHGVrSxlKfGYGPhcSjBUTCX7X6ncLRPMQV9Rtc7N7rF PLUUzlSb6eS3gqhXNYDAJTJYbJE6qcASMMnKXh1kqVZzQHbU40acRd8KkhPzJeSBDo 59OBzigY1FcDg== Received: from lists1.osuosl.org (lists1.osuosl.org [140.211.166.142]) by smtp3.osuosl.org (Postfix) with ESMTP id 71C79607F7; Sat, 14 Mar 2026 16:35:25 +0000 (UTC) Received: from smtp3.osuosl.org (smtp3.osuosl.org [140.211.166.136]) by lists1.osuosl.org (Postfix) with ESMTP id 5BC25201 for ; Sat, 14 Mar 2026 16:35:23 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp3.osuosl.org (Postfix) with ESMTP id 4722A607F7 for ; Sat, 14 Mar 2026 16:35:23 +0000 (UTC) X-Virus-Scanned: amavis at osuosl.org Received: from smtp3.osuosl.org ([127.0.0.1]) by localhost (smtp3.osuosl.org [127.0.0.1]) (amavis, port 10024) with ESMTP id zaRhkqfiusmR for ; Sat, 14 Mar 2026 16:35:22 +0000 (UTC) Received-SPF: Pass (mailfrom) identity=mailfrom; client-ip=172.105.4.254; helo=tor.source.kernel.org; envelope-from=kuba@kernel.org; receiver= DMARC-Filter: OpenDMARC Filter v1.4.2 smtp3.osuosl.org 6EDB8607E5 DKIM-Filter: OpenDKIM Filter v2.11.0 smtp3.osuosl.org 6EDB8607E5 Received: from tor.source.kernel.org (tor.source.kernel.org [172.105.4.254]) by smtp3.osuosl.org (Postfix) with ESMTPS id 6EDB8607E5 for ; Sat, 14 Mar 2026 16:35:22 +0000 (UTC) Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by tor.source.kernel.org (Postfix) with ESMTP id 00E5C60008; Sat, 14 Mar 2026 16:35:20 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9EF82C116C6; Sat, 14 Mar 2026 16:35:19 +0000 (UTC) Date: Sat, 14 Mar 2026 09:35:18 -0700 From: Jakub Kicinski To: netdev@vger.kernel.org Cc: =?UTF-8?B?QmrDtnJuIFTDtnBlbA==?= , Michael Chan , Pavan Chebbi , Andrew Lunn , "David S. Miller" , Eric Dumazet , Paolo Abeni , Simon Horman , linux-kselftest@vger.kernel.org, Willem de Bruijn , Shuah Khan , Maxime Chevallier , Andrew Lunn , intel-wired-lan@lists.osuosl.org, Przemek Kitszel Message-ID: <20260314093518.43b820b7@kernel.org> In-Reply-To: <20260313071322.3489243-1-bjorn@kernel.org> References: <20260313071322.3489243-1-bjorn@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-Mailman-Original-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1773506120; bh=L/eakVxCmU6z4MfVX/Tn/gRdChsPQgl7sUT4bvaSUng=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=Qjg3QaOwYiWXU5CENRLW0EU8+MysNrtBRN2lvo+qCMxW8LYTl2pHBh9iA9403VxSo 5dd8vVB4NmjmecXcm9k3ZqyWASernSVsaMKsS4LoG1EJf9fJ0r2Z9aWWZwd1M2+6eD mO6e5RDg2kBMD04bhJtS/FkC+tsPOiWBthQVCt0c7BYi8ENxytga7jlW2ofHhNCl3A mOu2WXZoc6VyfBoXP5h43Yp+NOy2yWtLyAr9og2MIkYWzJ66gQDdpYxOKfXKCLAq3C i3/TG5kz8TUhyZFL+pmVgsiG0vg7f/ZXhTEhlbe8Iu8M+iUjsRh2NvQMhHhcp8jX5e Z9V5Q4/GbV9tA== X-Mailman-Original-Authentication-Results: smtp3.osuosl.org; dmarc=pass (p=quarantine dis=none) header.from=kernel.org X-Mailman-Original-Authentication-Results: smtp3.osuosl.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=Qjg3QaOw Subject: Re: [Intel-wired-lan] [PATCH net-next v4 0/3] ethtool: Dynamic RSS context indirection table resizing X-BeenThere: intel-wired-lan@osuosl.org X-Mailman-Version: 2.1.30 Precedence: list List-Id: Intel Wired Ethernet Linux Kernel Driver Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-wired-lan-bounces@osuosl.org Sender: "Intel-wired-lan" On Fri, 13 Mar 2026 08:13:12 +0100 Bj=C3=B6rn T=C3=B6pel wrote: > Some NICs (e.g. bnxt) change their RSS indirection table size based on > the queue count, because the hardware table is a shared resource. The > ethtool core locks ctx->indir_size at context creation, so drivers > have to reject channel changes when RSS contexts exist. >=20 > This series adds resize helpers and wires them up in bnxt. Sorry Bjorn, I was typing the explanation below and I realized that=20 we may be violating user intent. We should already record the user_size from rss_set_prep_indir() as part of the context (and presumably some netdev state for the main context?) and don't allow shrinking the context below that mark.. Now for the broader audience - my understanding is that the RSS table is a precious resource for most if not all drivers. The direction of this work is to allow user to explicitly specify what RSS table size they want. The Netlink API for RSS already allows users to send tables smaller than what the device reports (Netlink code just "replicates" the table). So if the user asks for X entries the driver should be able to allocate a table of any size as long as its a multiple of X. This series only support "global" resizing but it should be simple to add the state for the driver to mark in the context what table size it actually allocated. The only reason we haven't added the support for that is that it's quite hard to know how to implement it without docs for the FW/HW.. fbnic has fixed table sizes so we can't even prototype there :S Please reply if you'd like to collaborate on adding support for the user-defined RSS context sizing.