From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759575AbXEYF7X (ORCPT ); Fri, 25 May 2007 01:59:23 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753472AbXEYF7P (ORCPT ); Fri, 25 May 2007 01:59:15 -0400 Received: from mx2.go2.pl ([193.17.41.42]:40555 "EHLO poczta.o2.pl" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752226AbXEYF7P (ORCPT ); Fri, 25 May 2007 01:59:15 -0400 Date: Fri, 25 May 2007 08:06:09 +0200 From: Jarek Poplawski To: Andrew Morton Cc: linux-kernel@vger.kernel.org Subject: Re: [PATCH] smpboot: cachesize comparison fix in smp_tune_scheduling() Message-ID: <20070525060609.GA985@ff.dom.local> References: <20070524103322.GA1920@ff.dom.local> <20070524160207.51a478cd.akpm@linux-foundation.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070524160207.51a478cd.akpm@linux-foundation.org> User-Agent: Mutt/1.4.2.2i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, May 24, 2007 at 04:02:07PM -0700, Andrew Morton wrote: > On Thu, 24 May 2007 12:33:23 +0200 > Jarek Poplawski wrote: > > > > > smpboot: cachesize comparison fix in smp_tune_scheduling() > > > > boot_cpu_data.x86_cache_size is signed int and can be < 0 too. ... > Under what conditions can boot_cpu_data.x86_cache_size be negative? > > Have negative values of boot_cpu_data.x86_cache_size been observed in > practice? Sorry, but IMHO every observations are only kind of illusions, and should have no influence on any serious science, including computer science. But, from smpboot.c history: "[PATCH] i386: Clean up smp_tune_scheduling() Adrian Bunk [Thu, 7 Dec 2006 01:14:19 +0000 (02:14 +0100)] - remove the write-only local variable "bandwidth" - don't set "max_cache_size" in the (cachesize < 0) case: that's already handled in kernel/sched.c:measure_migration_cost()" So, it seems such strange phenomenon could've been observed long time ago... Thanks, Jarek P.