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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 1EEEDC64E7B for ; Mon, 30 Nov 2020 16:15:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A32922076E for ; Mon, 30 Nov 2020 16:15:41 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="vl61i7wZ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728668AbgK3QPZ (ORCPT ); Mon, 30 Nov 2020 11:15:25 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35868 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727395AbgK3QPZ (ORCPT ); Mon, 30 Nov 2020 11:15:25 -0500 Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [IPv6:2001:4b98:dc2:55:216:3eff:fef7:d647]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id ED57CC0613CF; Mon, 30 Nov 2020 08:14:44 -0800 (PST) Received: from pendragon.ideasonboard.com (62-78-145-57.bb.dnainternet.fi [62.78.145.57]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id F3056B26; Mon, 30 Nov 2020 17:14:42 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1606752883; bh=hA1p7XG8OVMcXeYwF/6YL9wO3z01pSCZWxtyGUu6fyo=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=vl61i7wZjVlTraR4543dMM1TqEbfuwMkcocmenWCQgTQCWRuOo+3bNx1r7yB6I1+R TwmthV3GEpVkRU4hixPInkky0BiL1s+ssGA6U6uJm+ah6nUmTvhwDcTbIpoEJyCKCh kut3u9JA4dwhiKUD3YdMBfS3efTLOxY9noHrCbvo= Date: Mon, 30 Nov 2020 18:14:34 +0200 From: Laurent Pinchart To: Daniel Scally Cc: linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, linux-gpio@vger.kernel.org, linux-i2c@vger.kernel.org, linux-media@vger.kernel.org, devel@acpica.org, rjw@rjwysocki.net, lenb@kernel.org, gregkh@linuxfoundation.org, mika.westerberg@linux.intel.com, andriy.shevchenko@linux.intel.com, linus.walleij@linaro.org, bgolaszewski@baylibre.com, wsa@kernel.org, yong.zhi@intel.com, sakari.ailus@linux.intel.com, bingbu.cao@intel.com, tian.shu.qiu@intel.com, mchehab@kernel.org, robert.moore@intel.com, erik.kaneda@intel.com, pmladek@suse.com, rostedt@goodmis.org, sergey.senozhatsky@gmail.com, linux@rasmusvillemoes.dk, kieran.bingham+renesas@ideasonboard.com, jacopo+renesas@jmondi.org, laurent.pinchart+renesas@ideasonboard.com, jorhand@linux.microsoft.com, kitakar@gmail.com, heikki.krogerus@linux.intel.com Subject: Re: [PATCH 05/18] software_node: Alter software_node_unregister_nodes() to unregister the array in reverse order Message-ID: <20201130161434.GI14465@pendragon.ideasonboard.com> References: <20201130133129.1024662-1-djrscally@gmail.com> <20201130133129.1024662-6-djrscally@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20201130133129.1024662-6-djrscally@gmail.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Daniel, Thank you for the patch. On Mon, Nov 30, 2020 at 01:31:16PM +0000, Daniel Scally wrote: > Software nodes that are children of another software node should be > unregistered before their parent. To allow easy unregistering of an array > of software_nodes ordered parent to child, reverse the order in which > this function unregisters software_nodes. > > Suggested-by: Andy Shevchenko > Signed-off-by: Daniel Scally Reviewed-by: Laurent Pinchart > --- > Changes since RFC v3: > > Switched this functionality from a new function to replacing > the existing software_nodes_unregister_nodes() > > drivers/base/swnode.c | 19 ++++++++++++------- > 1 file changed, 12 insertions(+), 7 deletions(-) > > diff --git a/drivers/base/swnode.c b/drivers/base/swnode.c > index af7930b3679e..d39e1c76d98d 100644 > --- a/drivers/base/swnode.c > +++ b/drivers/base/swnode.c > @@ -720,20 +720,25 @@ EXPORT_SYMBOL_GPL(software_node_register_nodes); > > /** > * software_node_unregister_nodes - Unregister an array of software nodes > - * @nodes: Zero terminated array of software nodes to be unregistered > + * @nodes: Zero terminated array of software nodes to be unregistered. If > + * parent pointers are set up in any of the software nodes then the array > + * MUST be ordered such that parents come before their children. > * > * Unregister multiple software nodes at once. > * > - * NOTE: Be careful using this call if the nodes had parent pointers set up in > - * them before registering. If so, it is wiser to remove the nodes > - * individually, in the correct order (child before parent) instead of relying > - * on the sequential order of the list of nodes in the array. > + * NOTE: If you are uncertain whether the array is ordered such that > + * parents will be unregistered before their children, it is wiser to > + * remove the nodes individually, in the correct order (child before > + * parent). > */ > void software_node_unregister_nodes(const struct software_node *nodes) > { > - int i; > + unsigned int i = 0; > + > + while (nodes[i].name) > + i++; > > - for (i = 0; nodes[i].name; i++) > + while (i--) > software_node_unregister(&nodes[i]); > } > EXPORT_SYMBOL_GPL(software_node_unregister_nodes); -- Regards, Laurent Pinchart