From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757317AbbDPO1Z (ORCPT ); Thu, 16 Apr 2015 10:27:25 -0400 Received: from foss.arm.com ([217.140.101.70]:38207 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757167AbbDPO1I (ORCPT ); Thu, 16 Apr 2015 10:27:08 -0400 Date: Thu, 16 Apr 2015 15:27:03 +0100 From: Catalin Marinas To: "Dr. Philipp Tomsich" Cc: Andreas Kraschitzer , Arnd Bergmann , "Pinski, Andrew" , Andreas Schwab , Alexander Graf , "linux-kernel@vger.kernel.org" , Andrew Pinski , Kumar Sankaran , Benedikt Huber , linux-arm-kernel@lists.infradead.org, Christoph Muellner Subject: Re: [PATCH v4 00/24] ILP32 for ARM64 Message-ID: <20150416142703.GD819@e104818-lin.cambridge.arm.com> References: <025BB233-8D14-457A-B3B2-C6BD6C3B32EF@theobroma-systems.com> <20150415100153.GA11626@localhost> <2243754.JW5bGY74bP@wuerfel> <20150415153800.GG22741@localhost> <20150415172219.GE26099@e104818-lin.cambridge.arm.com> <552EE560.9070205@suse.de> <20150416110325.GB819@e104818-lin.cambridge.arm.com> <09A21550-3538-4A8E-AB12-A9A516D3E866@theobroma-systems.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <09A21550-3538-4A8E-AB12-A9A516D3E866@theobroma-systems.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Apr 16, 2015 at 01:19:14PM +0200, Dr. Philipp Tomsich wrote: > Just for the record (and to avoid anyone wasting their time on what’s available > today): we are migrating this over to option (a) now, even though we would > prefer to see option (b) implemented. > > If we get a consensus on (b) in the next couple of days, we’ll redo things for > option (b). If not, we will have an implementation for option (a) available that > we can hopefully all agree on merging. When you post, please include the libc-alpha list (I think they are fine with cross-posting), maybe only for the cover letter as that's where the useful discussion seems to happen. It's interesting to re-read some older posts on x32 (it's not just time_t affected, though probably that the most visible): https://lwn.net/Articles/457089/ https://sourceware.org/ml/libc-alpha/2012-03/msg00487.html https://sourceware.org/ml/libc-alpha/2012-03/msg00574.html Basically for x32 POSIX compliance doesn't seem too critical. IIUC, the x32 wasn't added to solve a 32-bit compatibility problem but as a potential optimisation for specific cases. On ARM OTOH, (one of?) the main goal for AArch64 ILP32 is to offer a solution for 32-bit code when AArch32 is not present (and potentially slightly more optimal than AArch32 but not necessarily when compared to LP64). -- Catalin From mboxrd@z Thu Jan 1 00:00:00 1970 From: catalin.marinas@arm.com (Catalin Marinas) Date: Thu, 16 Apr 2015 15:27:03 +0100 Subject: [PATCH v4 00/24] ILP32 for ARM64 In-Reply-To: <09A21550-3538-4A8E-AB12-A9A516D3E866@theobroma-systems.com> References: <025BB233-8D14-457A-B3B2-C6BD6C3B32EF@theobroma-systems.com> <20150415100153.GA11626@localhost> <2243754.JW5bGY74bP@wuerfel> <20150415153800.GG22741@localhost> <20150415172219.GE26099@e104818-lin.cambridge.arm.com> <552EE560.9070205@suse.de> <20150416110325.GB819@e104818-lin.cambridge.arm.com> <09A21550-3538-4A8E-AB12-A9A516D3E866@theobroma-systems.com> Message-ID: <20150416142703.GD819@e104818-lin.cambridge.arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Thu, Apr 16, 2015 at 01:19:14PM +0200, Dr. Philipp Tomsich wrote: > Just for the record (and to avoid anyone wasting their time on what?s available > today): we are migrating this over to option (a) now, even though we would > prefer to see option (b) implemented. > > If we get a consensus on (b) in the next couple of days, we?ll redo things for > option (b). If not, we will have an implementation for option (a) available that > we can hopefully all agree on merging. When you post, please include the libc-alpha list (I think they are fine with cross-posting), maybe only for the cover letter as that's where the useful discussion seems to happen. It's interesting to re-read some older posts on x32 (it's not just time_t affected, though probably that the most visible): https://lwn.net/Articles/457089/ https://sourceware.org/ml/libc-alpha/2012-03/msg00487.html https://sourceware.org/ml/libc-alpha/2012-03/msg00574.html Basically for x32 POSIX compliance doesn't seem too critical. IIUC, the x32 wasn't added to solve a 32-bit compatibility problem but as a potential optimisation for specific cases. On ARM OTOH, (one of?) the main goal for AArch64 ILP32 is to offer a solution for 32-bit code when AArch32 is not present (and potentially slightly more optimal than AArch32 but not necessarily when compared to LP64). -- Catalin