Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761718AbXLOW7x (ORCPT ); Sat, 15 Dec 2007 17:59:53 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1758912AbXLOW7i (ORCPT ); Sat, 15 Dec 2007 17:59:38 -0500 Received: from gprs189-60.eurotel.cz ([160.218.189.60]:37782 "EHLO amd.ucw.cz" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1757361AbXLOW7h (ORCPT ); Sat, 15 Dec 2007 17:59:37 -0500 Date: Sat, 15 Dec 2007 23:59:43 +0100 From: Pavel Machek To: Ingo Molnar Cc: Rene Herman , "David P. Reed" , Alan Cox , Thomas Gleixner , linux-kernel@vger.kernel.org, Ingo Molnar , "H. Peter Anvin" Subject: Re: [PATCH] x86_64: fix problems due to use of "outb" to port 80 on some AMD64x2 laptops, etc. Message-ID: <20071215225943.GE2434@elf.ucw.cz> References: <469578CD.3080609@reed.com> <1184216528.12353.203.camel@chaos> <1184218962.12353.209.camel@chaos> <46964352.7040301@reed.com> <1184253339.12353.223.camel@chaos> <469697C6.50903@reed.com> <1184274754.12353.254.camel@chaos> <4761F193.7090400@reed.com> <476250D5.8000409@gmail.com> <20071214142355.GA10130@elte.hu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20071214142355.GA10130@elte.hu> X-Warning: Reading this can be dangerous to your mental health. User-Agent: Mutt/1.5.16 (2007-06-11) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1328 Lines: 35 On Fri 2007-12-14 15:23:55, Ingo Molnar wrote: > > * Rene Herman wrote: > > > --- a/init/main.c > > +++ b/init/main.c > > @@ -229,10 +229,9 @@ static int __init obsolete_checksetup(char *line) > > } > > > > /* > > - * This should be approx 2 Bo*oMips to start (note initial shift), and will > > - * still work even if initially too large, it will just take slightly longer > > + * Initial value roughly corresponds to a 1 GHz CPU > > */ > > -unsigned long loops_per_jiffy = (1<<12); > > +unsigned long loops_per_jiffy = 1000000000 / HZ; > > > > EXPORT_SYMBOL(loops_per_jiffy); > > this is a factor of ~2400 increase - this will take an eternity to boot > on any older CPU. I don't think we are using outb_p before loops_per_jiffy are initialized -- I believe I'd see oopsen if we did. Factor 2400 increase is bad, but if it only converts 10x 1usec delay into 10x 24msec delay, it is not _that_ bad. Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html -- 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/