From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from sc8-sf-mx1-b.sourceforge.net ([10.3.1.91] helo=mail.sourceforge.net) by sc8-sf-list1.sourceforge.net with esmtp (Exim 4.30) id 1EUXB4-0005UP-NH for user-mode-linux-devel@lists.sourceforge.net; Tue, 25 Oct 2005 15:21:54 -0700 Received: from cantor2.suse.de ([195.135.220.15] helo=mx2.suse.de) by mail.sourceforge.net with esmtps (TLSv1:AES256-SHA:256) (Exim 4.44) id 1EUXB1-0007u5-UU for user-mode-linux-devel@lists.sourceforge.net; Tue, 25 Oct 2005 15:21:54 -0700 From: Andi Kleen References: <20051025221105.21106.95194.stgit@zion.home.lan> <20051025221351.21106.57194.stgit@zion.home.lan> In-Reply-To: <20051025221351.21106.57194.stgit@zion.home.lan> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200510260022.28095.ak@suse.de> Subject: [uml-devel] Re: [PATCH 6/6] x86_64: enable xchg optimization for x86_64 Sender: user-mode-linux-devel-admin@lists.sourceforge.net Errors-To: user-mode-linux-devel-admin@lists.sourceforge.net List-Unsubscribe: , List-Id: The user-mode Linux development list List-Post: List-Help: List-Subscribe: , List-Archive: Date: Wed, 26 Oct 2005 00:22:27 +0200 To: Paolo 'Blaisorblade' Giarrusso Cc: Andrew Morton , Jeff Dike , linux-kernel@vger.kernel.org, user-mode-linux-devel@lists.sourceforge.net On Wednesday 26 October 2005 00:13, Paolo 'Blaisorblade' Giarrusso wrote: > > I.e. the implementation was written, is present in the tree, but due to > this: > > #ifdef CONFIG_RWSEM_GENERIC_SPINLOCK > #include /* use a generic implementation */ > #else > #include /* use an arch-specific implementation */ > #endif > > it was probably _NEVER_ compiled!!! Actually it was, but we switched it back because there were some doubts on the correctness of the xchg based implementation and the generic one looked much cleaner. So far nobody showed a significant performance different too. I should probably remove asm/rwsem.h. Don't apply please. -Andi ------------------------------------------------------- This SF.Net email is sponsored by the JBoss Inc. Get Certified Today * Register for a JBoss Training Course Free Certification Exam for All Training Attendees Through End of 2005 Visit http://www.jboss.com/services/certification for more information _______________________________________________ User-mode-linux-devel mailing list User-mode-linux-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932425AbVJYWVr (ORCPT ); Tue, 25 Oct 2005 18:21:47 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932431AbVJYWVr (ORCPT ); Tue, 25 Oct 2005 18:21:47 -0400 Received: from ns2.suse.de ([195.135.220.15]:44515 "EHLO mx2.suse.de") by vger.kernel.org with ESMTP id S932425AbVJYWVq (ORCPT ); Tue, 25 Oct 2005 18:21:46 -0400 From: Andi Kleen To: "Paolo 'Blaisorblade' Giarrusso" Subject: Re: [PATCH 6/6] x86_64: enable xchg optimization for x86_64 Date: Wed, 26 Oct 2005 00:22:27 +0200 User-Agent: KMail/1.8 Cc: Andrew Morton , Jeff Dike , linux-kernel@vger.kernel.org, user-mode-linux-devel@lists.sourceforge.net References: <20051025221105.21106.95194.stgit@zion.home.lan> <20051025221351.21106.57194.stgit@zion.home.lan> In-Reply-To: <20051025221351.21106.57194.stgit@zion.home.lan> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200510260022.28095.ak@suse.de> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wednesday 26 October 2005 00:13, Paolo 'Blaisorblade' Giarrusso wrote: > > I.e. the implementation was written, is present in the tree, but due to > this: > > #ifdef CONFIG_RWSEM_GENERIC_SPINLOCK > #include /* use a generic implementation */ > #else > #include /* use an arch-specific implementation */ > #endif > > it was probably _NEVER_ compiled!!! Actually it was, but we switched it back because there were some doubts on the correctness of the xchg based implementation and the generic one looked much cleaner. So far nobody showed a significant performance different too. I should probably remove asm/rwsem.h. Don't apply please. -Andi