Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753887AbZI2TML (ORCPT ); Tue, 29 Sep 2009 15:12:11 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753762AbZI2TMK (ORCPT ); Tue, 29 Sep 2009 15:12:10 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:53368 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753572AbZI2TMJ (ORCPT ); Tue, 29 Sep 2009 15:12:09 -0400 Date: Tue, 29 Sep 2009 12:10:50 -0700 (PDT) From: Linus Torvalds X-X-Sender: torvalds@localhost.localdomain To: Arjan van de Ven cc: "H. Peter Anvin" , Roland McGrath , Sukadev Bhattiprolu , Arnd Bergmann , Containers , Nathan Lynch , linux-kernel@vger.kernel.org, "Eric W. Biederman" , mingo@elte.hu, Alexey Dobriyan , Pavel Emelyanov , linux-api@vger.kernel.org, kosaki.motohiro@jp.fujitsu.com Subject: Re: [RFC][v7][PATCH 8/9]: Define clone2() syscall In-Reply-To: <20090929210207.247b94df@infradead.org> Message-ID: References: <20090924165548.GA16586@us.ibm.com> <20090924170308.GH16989@us.ibm.com> <200909242343.59903.arnd@arndb.de> <20090925082346.GB4436@localdomain> <20090925105632.GG12824@hawkmoon.kerlabs.com> <20090929180537.GD4625@us.ibm.com> <20090929184023.532DF34@magilla.sf.frob.com> <4AC255A4.4030002@zytor.com> <20090929210207.247b94df@infradead.org> User-Agent: Alpine 2.01 (LFD 1184 2008-12-16) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1041 Lines: 27 On Tue, 29 Sep 2009, Arjan van de Ven wrote: > > > > We already have a syscall layer which is painful to thunk in places, > > and this would make it much worse. > > syscalls are cheap as well. > cheaper than decades of dealing with such multiplexer mess ;/ Well, I'd agree, except the clone flags really _are_ about multiplexer issues, and the new flag woudln't really change anything. If the new system call actually had appreciably separate code-paths, I'd buy the "multiplexer" argument. But it doesn't really. It's going to call down to the same basic clone functionality, and the core clone code ends up de-multiplexing the cases anyway. So this would not at all be like the socket calls (to pick the traditional Linux system call multiplexing example) in that sense. Linus -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/