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=-7.0 required=3.0 tests=BAYES_00, 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 8A089C433E0 for ; Thu, 23 Jul 2020 01:07:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6684B2080D for ; Thu, 23 Jul 2020 01:07:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1733288AbgGWBHT (ORCPT ); Wed, 22 Jul 2020 21:07:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38168 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728607AbgGWBHT (ORCPT ); Wed, 22 Jul 2020 21:07:19 -0400 Received: from shards.monkeyblade.net (shards.monkeyblade.net [IPv6:2620:137:e000::1:9]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6560DC0619DC for ; Wed, 22 Jul 2020 18:07:19 -0700 (PDT) Received: from localhost (unknown [IPv6:2601:601:9f00:477::3d5]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) (Authenticated sender: davem-davemloft) by shards.monkeyblade.net (Postfix) with ESMTPSA id E9979126B39BC; Wed, 22 Jul 2020 17:50:33 -0700 (PDT) Date: Wed, 22 Jul 2020 18:07:18 -0700 (PDT) Message-Id: <20200722.180718.1511521016153348074.davem@davemloft.net> To: parav@mellanox.com Cc: netdev@vger.kernel.org, kuba@kernel.org, jiri@mellanox.com Subject: Re: [PATCH net-next] devlink: Always use user_ptr[0] for devlink and simplify post_doit From: David Miller In-Reply-To: <20200722155711.976214-1-parav@mellanox.com> References: <20200722155711.976214-1-parav@mellanox.com> X-Mailer: Mew version 6.8 on Emacs 26.3 Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Wed, 22 Jul 2020 17:50:34 -0700 (PDT) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Parav Pandit Date: Wed, 22 Jul 2020 18:57:11 +0300 > Currently devlink instance is searched on all doit() operations. > But it is optionally stored into user_ptr[0]. This requires > rediscovering devlink again doing post_doit(). > > Few devlink commands related to port shared buffers needs 3 pointers > (devlink, devlink_port, and devlink_sb) while executing doit commands. > Though devlink pointer can be derived from the devlink_port during > post_doit() operation when doit() callback has acquired devlink > instance lock, relying on such scheme to access devlik pointer makes > code very fragile. > > Hence, to avoid ambiguity in post_doit() and to avoid searching > devlink instance again, simplify code by always storing devlink > instance in user_ptr[0] and derive devlink_sb pointer in their > respective callback routines. > > Signed-off-by: Parav Pandit > Reviewed-by: Jiri Pirko Applied.