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 alsa0.perex.cz (alsa0.perex.cz [77.48.224.243]) (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 C9AABC4321E for ; Fri, 2 Dec 2022 13:12:28 +0000 (UTC) Received: from alsa1.perex.cz (alsa1.perex.cz [207.180.221.201]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by alsa0.perex.cz (Postfix) with ESMTPS id 51F251728; Fri, 2 Dec 2022 14:11:36 +0100 (CET) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa0.perex.cz 51F251728 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=alsa-project.org; s=default; t=1669986746; bh=p4GYPrcLemfL1H4zQdK4YSafqKxYl8uzcCcsuNR5Mug=; h=Date:From:To:Subject:References:In-Reply-To:Cc:List-Id: List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe: From; b=CmCYhhI57y0YWALB8N0T4BPAlLJvyI+OoRAPJJCLyqgsJawMyfaCt9S9aLNgsI4+o pYEzQIetaSUk+YbyKHRdJ6R3PS5jBYIUDg7HLrcBTwAAor6ooU+2UY1Q7h2JU102o8 MLgPTVl4yB/qGe1C06qxhN5dnTPdnvv6ox9FN/A0= Received: from alsa1.perex.cz (localhost.localdomain [127.0.0.1]) by alsa1.perex.cz (Postfix) with ESMTP id EDD35F80272; Fri, 2 Dec 2022 14:11:35 +0100 (CET) Received: by alsa1.perex.cz (Postfix, from userid 50401) id 4BCD8F8028D; Thu, 1 Dec 2022 19:43:30 +0100 (CET) Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by alsa1.perex.cz (Postfix) with ESMTPS id 4FDB2F80116 for ; Thu, 1 Dec 2022 19:43:27 +0100 (CET) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa1.perex.cz 4FDB2F80116 Authentication-Results: alsa1.perex.cz; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="a2BoPen0" Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id ADE6A620C3; Thu, 1 Dec 2022 18:43:24 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 208F8C433D6; Thu, 1 Dec 2022 18:43:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1669920204; bh=p4GYPrcLemfL1H4zQdK4YSafqKxYl8uzcCcsuNR5Mug=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=a2BoPen065qBe8Og5canw6L1zfhJNTp7AhJG9KCJ6kiqz0PbaFOGVhFTqYEHLQC/3 txrNOo/kDMMWMmzGqvPwfOzgrz6vwm2Q1DicWoYbq+xwADN5A7BOVkCSHc8BU+fkbm ahiTJmpUWGq4d9z7eAd6F7xiHvrsPEH9AaFENflI= Date: Thu, 1 Dec 2022 19:43:20 +0100 From: Greg Kroah-Hartman To: Matthew Wilcox Subject: Re: [PATCH 3/5] driver core: make struct device_type.uevent() take a const * Message-ID: References: <97be39ed-3cea-d55a-caa6-c2652baef399@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Mailman-Approved-At: Fri, 02 Dec 2022 14:11:34 +0100 Cc: Alexandre Belloni , Heikki Krogerus , Sean Young , "Rafael J. Wysocki" , alsa-devel@alsa-project.org, platform-driver-x86@vger.kernel.org, linux-i2c@vger.kernel.org, Andreas Noever , linux-i3c@lists.infradead.org, linux1394-devel@lists.sourceforge.net, Frank Rowand , Dan Williams , Andy Shevchenko , linux-acpi@vger.kernel.org, Bard Liao , Pierre-Louis Bossart , Jason Gunthorpe , Alan Stern , linux-serial@vger.kernel.org, linux-input@vger.kernel.org, Won Chung , Len Brown , devicetree@vger.kernel.org, Chaitanya Kulkarni , Ira Weiny , Michael Jamet , Ming Lei , Mark Gross , Hans de Goede , Rob Herring , Jiri Slaby , Thomas Gleixner , Mauro Carvalho Chehab , Mika Westerberg , Jens Axboe , linux-block@vger.kernel.org, Jilin Yuan , "Martin K. Petersen" , Dmitry Torokhov , linux-kernel@vger.kernel.org, Wolfram Sang , Vinod Koul , Stefan Richter , Sakari Ailus , Yehezkel Bernat , Sanyog Kale , linux-media@vger.kernel.org, Maximilian Luz , linux-usb@vger.kernel.org X-BeenThere: alsa-devel@alsa-project.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: "Alsa-devel mailing list for ALSA developers - http://www.alsa-project.org" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: "Alsa-devel" On Wed, Nov 23, 2022 at 06:00:23PM +0000, Matthew Wilcox wrote: > On Wed, Nov 23, 2022 at 01:55:42PM -0400, Jason Gunthorpe wrote: > > On Wed, Nov 23, 2022 at 05:49:36PM +0000, Matthew Wilcox wrote: > > > On Wed, Nov 23, 2022 at 01:29:56PM -0400, Jason Gunthorpe wrote: > > > > #define generic_container_of(in_type, in, out_type, out_member) \ > > > > _Generic(in, \ > > > > const in_type *: ((const out_type *)container_of(in, out_type, out_member)), \ > > > > in_type *: ((out_type *)container_of(in, out_type, out_member)) \ > > > > ) > > > > > > There's a neat trick I found in seqlock.h: > > > > > > #define generic_container_of(in_t, in, out_t, m) \ > > > _Generic(*(in), \ > > > const in_t: ((const out_t *)container_of(in, out_t, m)), \ > > > in_t: ((out_t *)container_of(in, out_type, m)) \ > > > ) > > > > > > and now it fits in 80 columns ;-) > > > > Aside from less letters, is their another benifit to using *(in) ? > > I don't think so. It just looks nicer to me than putting the star in > each case. If I'd thought of it, I would have done it to page_folio(), > but I won't change it now. Ah, but your trick will not work, that blows up and will not build. The original one from Jason here does work. _Generic is tricky... thanks, greg k-h