Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Sat, 16 Mar 2002 07:42:35 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Sat, 16 Mar 2002 07:42:26 -0500 Received: from mail.ocs.com.au ([203.34.97.2]:43025 "HELO mail.ocs.com.au") by vger.kernel.org with SMTP id ; Sat, 16 Mar 2002 07:42:20 -0500 X-Mailer: exmh version 2.2 06/23/2000 with nmh-1.0.4 From: Keith Owens To: Paul Gortmaker Cc: linux-kernel@vger.kernel.org Subject: Re: [PATCH] Speedup SMP kernel on UP box In-Reply-To: Your message of "Sat, 16 Mar 2002 06:51:35 CDT." <3C9331C7.5BDDE3BA@yahoo.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Sat, 16 Mar 2002 23:42:10 +1100 Message-ID: <16495.1016282530@ocs3.intra.ocs.com.au> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 16 Mar 2002 06:51:35 -0500, Paul Gortmaker wrote: >I had a think on this from the perspective of increasing UP performance >of SMP kernels, and came up with the following rather interesting (IMHO) >patch. Executive summary is that when a SMP kernel finds itself on a UP >box, it modifies itself (ooohh!) by going along and essentially doing a >sed '_text,_etext s/lock/nop/' :) > >Details: Address of each relevant lock opcode is stored (similar to >the way an exception table is) Does your patch work with recent binutils? I suspect that any lock code in discarded exit sections will cause binutils to barf (loudly). Look at the out of line changes to the lock code in 2.4.18-pre3, I had to stop using a single lock section because of the more rigorous binutils checks. - 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/