From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753523AbdJNDBW (ORCPT ); Fri, 13 Oct 2017 23:01:22 -0400 Received: from one.firstfloor.org ([193.170.194.197]:34910 "EHLO one.firstfloor.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753172AbdJNDBT (ORCPT ); Fri, 13 Oct 2017 23:01:19 -0400 Date: Fri, 13 Oct 2017 20:01:16 -0700 From: Andi Kleen To: Linus Torvalds Cc: Ben Maurer , Mathieu Desnoyers , David Goldblatt , Qi Wang , "Paul E. McKenney" , Boqun Feng , Peter Zijlstra , Paul Turner , Andrew Hunter , Andy Lutomirski , Dave Watson , Josh Triplett , Will Deacon , Linux Kernel Mailing List , Thomas Gleixner , Andi Kleen , Chris Lameter , Ingo Molnar , "H. Peter Anvin" , Steven Rostedt , Andrew Morton , Russell King , Catalin Marinas , Michael Kerrisk , Alexander Viro , Linux API Subject: Re: [RFC PATCH v9 for 4.15 01/14] Restartable sequences system call Message-ID: <20171014030116.GM2482@two.firstfloor.org> References: <20171012230326.19984-1-mathieu.desnoyers@efficios.com> <20171012230326.19984-2-mathieu.desnoyers@efficios.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: 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 > That sounds so obvious and stupid that you might go "What do you > mean?", but for things to work for libraries, they have to work > together with *other* users, and with *independent* users. As far as I can see the current model fundamentally only works for one user per process (because there is only a single range and abort IP) So once malloc started using it noone else could. Since malloc is the primary user it would be pointless to ever try it on something else. It seems fixing that would complicate everything quite a bit -- all ranges would need to be (unlimited?) arrays. -Andi From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andi Kleen Subject: Re: [RFC PATCH v9 for 4.15 01/14] Restartable sequences system call Date: Fri, 13 Oct 2017 20:01:16 -0700 Message-ID: <20171014030116.GM2482@two.firstfloor.org> References: <20171012230326.19984-1-mathieu.desnoyers@efficios.com> <20171012230326.19984-2-mathieu.desnoyers@efficios.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Linus Torvalds Cc: Ben Maurer , Mathieu Desnoyers , David Goldblatt , Qi Wang , "Paul E. McKenney" , Boqun Feng , Peter Zijlstra , Paul Turner , Andrew Hunter , Andy Lutomirski , Dave Watson , Josh Triplett , Will Deacon , Linux Kernel Mailing List , Thomas Gleixner , Andi Kleen , Chris Lameter , Ingo Molnar , "H. Peter Anvin" , Steven Rostedt Andrew List-Id: linux-api@vger.kernel.org > That sounds so obvious and stupid that you might go "What do you > mean?", but for things to work for libraries, they have to work > together with *other* users, and with *independent* users. As far as I can see the current model fundamentally only works for one user per process (because there is only a single range and abort IP) So once malloc started using it noone else could. Since malloc is the primary user it would be pointless to ever try it on something else. It seems fixing that would complicate everything quite a bit -- all ranges would need to be (unlimited?) arrays. -Andi