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=-6.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 D32ADC56201 for ; Fri, 30 Oct 2020 06:41:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5959022203 for ; Fri, 30 Oct 2020 06:41:09 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="FBGZC6KO"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="+McG+/Ep" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725827AbgJ3GlI (ORCPT ); Fri, 30 Oct 2020 02:41:08 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:40254 "EHLO galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725355AbgJ3GlI (ORCPT ); Fri, 30 Oct 2020 02:41:08 -0400 From: Kurt Kanzenbach DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1604040066; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=oGUugxoRy6Kt+rNkQvB6dvhrL/E4cemjCK8GQAqgmeo=; b=FBGZC6KO8YQewVsg+gOZ3GqdRaHi84PjWPwz9Wg9ARlr9fxPnvQ59HQ9rdFH1sdLJSEZPr a1zm1rJvVbhu3baXw3T/IJwCNjys5AveyI7f6BzOh28WfWurrdAhw9YRrVYxdEUWHW89p0 pRPkn/NVO4+vIrxj9rpdCif6pLYnUdyoKvLzkL+ojjedgrk6De1hpIU8eJlU71k8y9HnnU M09yzeFGWXxPgXshERjKESUw1nAlkKnPK//QgblROj+gGCGZ4DY+4bUO8NQaRyRLIV9yyI t/xLhN90CxJaxVp46XXG2ZI9RcSQVaL5Vhhc0BdGfU31pZrY6MkfzsdhMznLoA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1604040066; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=oGUugxoRy6Kt+rNkQvB6dvhrL/E4cemjCK8GQAqgmeo=; b=+McG+/EpqkxBcf83yfuTMOy79MHdqwvF2QFX/F/Op55xOhJkLQF9JlROeAsklykYWV18G8 C/QzG3aiJqEqCGDw== To: Vladimir Oltean , netdev@vger.kernel.org Cc: andrew@lunn.ch, f.fainelli@gmail.com, vivien.didelot@gmail.com, kuba@kernel.org, Christian Eggers Subject: Re: [PATCH v2 net-next 01/12] net: dsa: implement a central TX reallocation procedure In-Reply-To: <20201030014910.2738809-2-vladimir.oltean@nxp.com> References: <20201030014910.2738809-1-vladimir.oltean@nxp.com> <20201030014910.2738809-2-vladimir.oltean@nxp.com> Date: Fri, 30 Oct 2020 07:41:05 +0100 Message-ID: <87imas9pxa.fsf@kurt> MIME-Version: 1.0 Content-Type: multipart/signed; boundary="=-=-="; micalg=pgp-sha512; protocol="application/pgp-signature" Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org --=-=-= Content-Type: text/plain On Fri Oct 30 2020, Vladimir Oltean wrote: > At the moment, taggers are left with the task of ensuring that the skb > headers are writable (which they aren't, if the frames were cloned for > TX timestamping, for flooding by the bridge, etc), and that there is > enough space in the skb data area for the DSA tag to be pushed. > > Moreover, the life of tail taggers is even harder, because they need to > ensure that short frames have enough padding, a problem that normal > taggers don't have. > > The principle of the DSA framework is that everything except for the > most intimate hardware specifics (like in this case, the actual packing > of the DSA tag bits) should be done inside the core, to avoid having > code paths that are very rarely tested. > > So provide a TX reallocation procedure that should cover the known needs > of DSA today. > > Note that this patch also gives the network stack a good hint about the > headroom/tailroom it's going to need. Up till now it wasn't doing that. > So the reallocation procedure should really be there only for the > exceptional cases, and for cloned packets which need to be unshared. > The tx_reallocs counter should prove that. > > Signed-off-by: Vladimir Oltean > Tested-by: Christian Eggers # For tail taggers only Tested-by: Kurt Kanzenbach I'll wait with the hellcreek series until this is merged. Thanks, Kurt --=-=-= Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAEBCgAdFiEEooWgvezyxHPhdEojeSpbgcuY8KYFAl+btYEACgkQeSpbgcuY 8KYabA/+NCN7q/A7Nhv35ni4l+VA0reY/n/2LDVtMmYFmvpYffxhWUiQcZqChimD /u0BEJjdOWOjgu6izOobNtGzl72lMjfVOD2F38NOuWjNz3mFPmIrbx6NgsbTGyBy wmkNIvWwLAB7yfmM7dOo/J8YMncRhUBBiaATpdFyCWH3rkmgiZNcabEVbKnz0iSW uMlqvusQgkwDdqljDdRT1z2AA81pkwCPHGEb5hDx4MINGDsylfTu/xH9E7sVWknw 4PWEjq/gOjc/nlYnmS8bU6w+4qW0RmnTywowIg0/RXAyt0A7Ib5X0umGFlUuGI8d /PBi0AnFUHqK+I0AkFi+MXFBQKBpgQ1DXwavpRo2DymfG+9OzarkbBru7Gtlqbzs 6BPuhFwOku6v+NeHBGcPVEy1zxpsbxCefYTzzpuQT9GDKsLCc9nEygy7eF20djr0 7aDBp2wM97Z/kFTXImMkUGXpBEqwGVM1Ak6GZyF7M45jGqoKYZX8ZT1b+hNsWE1h 9p+n3c4J93iu9tpW1y34RavAJiY/z7Yse4KpSrUC0y0Exb4D2HdSbx+siOT3gMwf 8AO9Uuksq4Ki9IuxPhxZ6E0riuV/e+0jTukmjvW0bsX8TfYjd7AnxugcueCv0bmI II6mx5a50OHL0+cybYTdZfyYcCzqsS5lqjgVPhHAo0dZnSQrXJ4= =dWwU -----END PGP SIGNATURE----- --=-=-=--