Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751082AbVLPKqi (ORCPT ); Fri, 16 Dec 2005 05:46:38 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750939AbVLPKqi (ORCPT ); Fri, 16 Dec 2005 05:46:38 -0500 Received: from mx1.redhat.com ([66.187.233.31]:32185 "EHLO mx1.redhat.com") by vger.kernel.org with ESMTP id S1750938AbVLPKqh (ORCPT ); Fri, 16 Dec 2005 05:46:37 -0500 From: David Howells In-Reply-To: <20051215121817.2abb0166.akpm@osdl.org> References: <20051215121817.2abb0166.akpm@osdl.org> <20051214155432.320f2950.akpm@osdl.org> <1134559121.25663.14.camel@localhost.localdomain> <13820.1134558138@warthog.cambridge.redhat.com> <20051213143147.d2a57fb3.pj@sgi.com> <20051213094053.33284360.pj@sgi.com> <20051212161944.3185a3f9.akpm@osdl.org> <20051213075441.GB6765@elte.hu> <20051213090219.GA27857@infradead.org> <20051213093949.GC26097@elte.hu> <20051213100015.GA32194@elte.hu> <6281.1134498864@warthog.cambridge.redhat.com> <14242.1134558772@warthog.cambridge.redhat.com> <16315.1134563707@warthog.cambridge.redhat.com> <1134568731.4275.4.camel@tglx.tec.linutronix.de> <43A0AD54.6050109@rtr.ca> <4336.1134661053@warthog.cambridge.redhat.com> <20051215112855.31669dc1.akpm@osdl.org> To: Andrew Morton Cc: dhowells@redhat.com, lkml@rtr.ca, tglx@linutronix.de, alan@lxorguk.ukuu.org.uk, pj@sgi.com, mingo@elte.hu, hch@infradead.org, torvalds@osdl.org, arjan@infradead.org, matthew@wil.cx, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org Subject: Re: [PATCH 1/19] MUTEX: Introduce simple mutex implementation X-Mailer: MH-E 7.84; nmh 1.1; GNU Emacs 22.0.50.1 Date: Fri, 16 Dec 2005 10:45:58 +0000 Message-ID: <10838.1134729958@warthog.cambridge.redhat.com> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 819 Lines: 19 Andrew Morton wrote: > Look at it from the POV of major architectures: there's no way the new > mutex code will be faster than down() and up() I'm thinking of making the default implementation of mutexes a straight wrapper around down() and up(). That way it'll be exactly the same as counting semaphores, just with extra constraints when the debugging is enabled _and_ effectively extra inline documentation. But! for archs where it does matter (and we have several - you might not care, but others do), it can be overridden with something faster. David - 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/