Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751238AbWH0WO4 (ORCPT ); Sun, 27 Aug 2006 18:14:56 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751239AbWH0WO4 (ORCPT ); Sun, 27 Aug 2006 18:14:56 -0400 Received: from omx2-ext.sgi.com ([192.48.171.19]:36487 "EHLO omx2.sgi.com") by vger.kernel.org with ESMTP id S1751238AbWH0WOz (ORCPT ); Sun, 27 Aug 2006 18:14:55 -0400 Date: Sun, 27 Aug 2006 15:14:50 -0700 (PDT) From: Christoph Lameter To: Andi Kleen cc: Dong Feng , Paul Mackerras , linux-kernel@vger.kernel.org Subject: Re: Why Semaphore Hardware-Dependent? In-Reply-To: <200608272339.08092.ak@suse.de> Message-ID: References: <200608272252.48946.ak@suse.de> <200608272339.08092.ak@suse.de> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 560 Lines: 14 On Sun, 27 Aug 2006, Andi Kleen wrote: > x86-64 always uses the spinlocked version (vs i386 using the atomic one) > and I haven't heard of anybody complaining. Ia64 has special counters for rwsemaphores. I'd like to see if there is any performance loss. mmap_sem is a rwsemaphore. This is performance critical. - 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/