Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030222AbVLVRRx (ORCPT ); Thu, 22 Dec 2005 12:17:53 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1030221AbVLVRRx (ORCPT ); Thu, 22 Dec 2005 12:17:53 -0500 Received: from pentafluge.infradead.org ([213.146.154.40]:8071 "EHLO pentafluge.infradead.org") by vger.kernel.org with ESMTP id S1030222AbVLVRRw (ORCPT ); Thu, 22 Dec 2005 12:17:52 -0500 Date: Thu, 22 Dec 2005 17:17:47 +0000 From: Christoph Hellwig To: Andrew Morton Cc: Arjan van de Ven , mingo@elte.hu, linux-kernel@vger.kernel.org, torvalds@osdl.org, arjanv@infradead.org, nico@cam.org, jes@trained-monkey.org, zwane@arm.linux.org.uk, oleg@tv-sign.ru, dhowells@redhat.com, alan@lxorguk.ukuu.org.uk, bcrl@kvack.org, rostedt@goodmis.org, hch@infradead.org, ak@suse.de, rmk+lkml@arm.linux.org.uk Subject: Re: [patch 0/9] mutex subsystem, -V4 Message-ID: <20051222171747.GA6038@infradead.org> Mail-Followup-To: Christoph Hellwig , Andrew Morton , Arjan van de Ven , mingo@elte.hu, linux-kernel@vger.kernel.org, torvalds@osdl.org, arjanv@infradead.org, nico@cam.org, jes@trained-monkey.org, zwane@arm.linux.org.uk, oleg@tv-sign.ru, dhowells@redhat.com, alan@lxorguk.ukuu.org.uk, bcrl@kvack.org, rostedt@goodmis.org, ak@suse.de, rmk+lkml@arm.linux.org.uk References: <20051222114147.GA18878@elte.hu> <20051222035443.19a4b24e.akpm@osdl.org> <20051222122011.GA20789@elte.hu> <20051222050701.41b308f9.akpm@osdl.org> <1135257829.2940.19.camel@laptopd505.fenrus.org> <20051222054413.c1789c43.akpm@osdl.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20051222054413.c1789c43.akpm@osdl.org> User-Agent: Mutt/1.4.2.1i X-SRS-Rewrite: SMTP reverse-path rewritten from by pentafluge.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 970 Lines: 21 On Thu, Dec 22, 2005 at 05:44:13AM -0800, Andrew Morton wrote: > > You keep saying 10 times "so please enhance semaphores to do this". > > Well I think diligence requires that we be able to demonstrate why it's not > possible. > > It's plain dumb for us to justify a fancy-pants new system based on > features which we could have added to the old one, no? But why should we add features to the semaphores. There's very little users of those real semaphore semantics, and they could do with a generic, all-C implementation because they are not important fast-pathes. OTOH we have lots of places needing plain mutex semantics, that are important fastpathes. Let's optimize for the common case instead of the corner case. - 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/