From mboxrd@z Thu Jan 1 00:00:00 1970 Received: with ECARTIS (v1.0.0; list linux-mips); Thu, 24 Apr 2003 18:03:33 +0100 (BST) Received: from mms2.broadcom.com ([IPv6:::ffff:63.70.210.59]:35851 "EHLO mms2.broadcom.com") by linux-mips.org with ESMTP id ; Thu, 24 Apr 2003 18:03:19 +0100 Received: from 63.70.210.1 by mms2.broadcom.com with ESMTP (Broadcom SMTP Relay (MMS v5.5.2)); Thu, 24 Apr 2003 10:00:01 -0700 Received: from mail-sj1-5.sj.broadcom.com (mail-sj1-5.sj.broadcom.com [10.16.128.236]) by mon-irva-11.broadcom.com (8.9.1/8.9.1) with ESMTP id KAA24260; Thu, 24 Apr 2003 10:02:47 -0700 (PDT) Received: from dt-sj3-158.sj.broadcom.com (dt-sj3-158 [10.21.64.158]) by mail-sj1-5.sj.broadcom.com (8.12.9/8.12.4/SSF) with ESMTP id h3OH35ml000328; Thu, 24 Apr 2003 10:03:05 -0700 (PDT) Received: from broadcom.com (IDENT:kwalker@localhost [127.0.0.1]) by dt-sj3-158.sj.broadcom.com (8.9.3/8.9.3) with ESMTP id KAA30042; Thu, 24 Apr 2003 10:03:05 -0700 Message-ID: <3EA818C9.3E46E560@broadcom.com> Date: Thu, 24 Apr 2003 10:03:05 -0700 From: "Kip Walker" Organization: Broadcom Corp. BPBU X-Mailer: Mozilla 4.79 [en] (X11; U; Linux 2.4.5-beta4va3.20 i686) X-Accept-Language: en MIME-Version: 1.0 To: "Jun Sun" cc: "Ralf Baechle" , linux-mips@linux-mips.org Subject: Re: [pathch] kernel/sched.c bogon? References: <3E67EF64.152CFC6C@broadcom.com> <20030306174001.K26071@mvista.com> <20030310135531.B2206@linux-mips.org> <20030310095907.U26071@mvista.com> X-WSS-ID: 12B6C79B1384662-01-01 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Return-Path: X-Envelope-To: <"|/home/ecartis/ecartis -s linux-mips"> (uid 0) X-Orcpt: rfc822;linux-mips@linux-mips.org Original-Recipient: rfc822;linux-mips@linux-mips.org X-archive-position: 2167 X-ecartis-version: Ecartis v1.0.0 Sender: linux-mips-bounce@linux-mips.org Errors-to: linux-mips-bounce@linux-mips.org X-original-sender: kwalker@broadcom.com Precedence: bulk X-list: linux-mips Jun Sun wrote: > > On Mon, Mar 10, 2003 at 01:55:31PM +0100, Ralf Baechle wrote: > > On Thu, Mar 06, 2003 at 05:40:01PM -0800, Jun Sun wrote: > > > > > I reported this bug last May. Apparently it is still not > > > taken up-stream. Ralf, why don't we fix it here and push > > > it up from you? > > > > > > BTW, this bug actually has effect on real-time performance under > > > preemptible kernel. > > > > < = 2.4.x preemptible kernel is OPP. > > > > > It can delay the execution of the highest > > > priority real-time process from execution up to 1 jiffy. > > > > Quite a number of users get_cycles() in the kernel assume it to return a > > 64-bit number. I guess we'll have to fake a 64-bit counter in software ... > > > > Whether we fake 64-bit or not, oldest_idle is declared as cycles_t. > So comparing it with (cycles_t)-1 should be always be correct. And it > actually makes a correct C program. :-) > > I don't see any possible reason for rejecting the change. My previous > report is probably just lost in the noise. And once again, the patch hasn't made it in. Can we either apply it get a good reason not to? Kip