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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 9AA71C63708 for ; Fri, 25 Nov 2022 21:21:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=xkm6GY9iFPoyA/fUjVG7SsA3Izhh1G3m/FbTSXx6Eqo=; b=vtXGin5qLDH/1P XaPyi0Qkok61h6t1Bf6FBRAKF/t9XZtLNjpzK9XPulJ5Ko4koqvyZLNzJjsn6bY1x1nko4t7TbG+x MjYuHRfm26fJah3VrAQb0kuc0FEy6YobYTttAHTIcZjo6HdowDwal3Lh28nLBu8R6cOSLlc9s1hY8 oHuk0iefz3VHdr88jI4jdpYY4ewSy6AoykQLwpQLAxuxWkiXv9KcHe/u1+l6Be93fk+qkUp7Boo0J kgO2E1nQmeoid7rKK32SoJbz/RJ0DBFFgSkIqfDRfzvo482OXBONBn2zTMZlSbME6WbLlVhDaRo93 fWifS8phA1r3vQFDK5Zw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1oyg8K-002E6T-3F; Fri, 25 Nov 2022 21:21:16 +0000 Received: from ams.source.kernel.org ([2604:1380:4601:e00::1]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1oxv4j-001sB1-Q0 for linux-i3c@lists.infradead.org; Wed, 23 Nov 2022 19:06:27 +0000 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 ams.source.kernel.org (Postfix) with ESMTPS id 16BBFB82405; Wed, 23 Nov 2022 19:06:24 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D7968C433D6; Wed, 23 Nov 2022 19:06:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1669230382; bh=imibZHjJL9cpBpAGiGFcUllw5xFRNIsDuHu6Y+fwag4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=V2GZdWHPvr+u9NV42kW3apisS1jk4Cp6h19MZ6qfaWIUGIVJV5gV2ha39zpYgwqP7 WIt60wd9b8FvKniDUGYZZUiLCvZQFxPf+YdmrcSFnI46/b/EWX33zlFDz2TQxA125f 2aOS9p5Y/Iiz28acyMaujccSu8U/Ol2yQw6Symkw= Date: Wed, 23 Nov 2022 20:06:20 +0100 From: Greg Kroah-Hartman To: Jason Gunthorpe Cc: Matthew Wilcox , Maximilian Luz , Andy Shevchenko , linux-kernel@vger.kernel.org, Jens Axboe , "Rafael J. Wysocki" , Len Brown , Stefan Richter , Wolfram Sang , Alexandre Belloni , Dmitry Torokhov , Sean Young , Mauro Carvalho Chehab , Rob Herring , Frank Rowand , Hans de Goede , Mark Gross , Vinod Koul , Bard Liao , Pierre-Louis Bossart , Sanyog Kale , Andreas Noever , Michael Jamet , Mika Westerberg , Yehezkel Bernat , Jiri Slaby , Heikki Krogerus , "Martin K. Petersen" , Chaitanya Kulkarni , Ming Lei , Jilin Yuan , Alan Stern , Sakari Ailus , Thomas Gleixner , Ira Weiny , Dan Williams , Won Chung , alsa-devel@alsa-project.org, devicetree@vger.kernel.org, linux-acpi@vger.kernel.org, linux-block@vger.kernel.org, linux-i2c@vger.kernel.org, linux-i3c@lists.infradead.org, linux-input@vger.kernel.org, linux-media@vger.kernel.org, linux-serial@vger.kernel.org, linux-usb@vger.kernel.org, linux1394-devel@lists.sourceforge.net, platform-driver-x86@vger.kernel.org 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-Disposition: inline In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20221123_110626_247361_47A17D7D X-CRM114-Status: GOOD ( 24.24 ) X-Mailman-Approved-At: Fri, 25 Nov 2022 13:21:11 -0800 X-BeenThere: linux-i3c@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-i3c" Errors-To: linux-i3c-bounces+linux-i3c=archiver.kernel.org@lists.infradead.org On Wed, Nov 23, 2022 at 02:25:59PM -0400, Jason Gunthorpe wrote: > On Wed, Nov 23, 2022 at 07:10:49PM +0100, Greg Kroah-Hartman 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 ;-) > > > > Nice trick! Dropping the inline functions is a bit different, let me > > see if that still gives a sane error if we pass an incorrect type or > > mess with the const * the wrong way. I'll run some tests tomorrow > > afternoon... > > The errors in some cases are very verbose, but it is somewhat > understandable - the worst is when _Generic fails to match anything, > but also at least clang partially expanded container_of and it throws > other assertions too. > > I also wonder if this could just be rolled into the normal > container_of. I think we might be able to now, my previous attempts with inline functions prevented that. I'll beat on that tomorrow... > in_type would have to be derived like: > > in_type = typeof((out_type *)NULL)->out_member) > > But I don't know if you can use typeof in a generic type matching expression.. Maybe that is what threw me before, I can't remember. I do know we tried a number of different attempts, can't recall the failed ones... thanks, greg k-h -- linux-i3c mailing list linux-i3c@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-i3c