Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261180AbVA0U6Y (ORCPT ); Thu, 27 Jan 2005 15:58:24 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261198AbVA0Uyw (ORCPT ); Thu, 27 Jan 2005 15:54:52 -0500 Received: from gateway-1237.mvista.com ([12.44.186.158]:25078 "EHLO av.mvista.com") by vger.kernel.org with ESMTP id S261197AbVA0Uxk (ORCPT ); Thu, 27 Jan 2005 15:53:40 -0500 Message-ID: <41F954CE.6040504@mvista.com> Date: Thu, 27 Jan 2005 12:53:34 -0800 From: George Anzinger Reply-To: george@mvista.com Organization: MontaVista Software User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.4.2) Gecko/20040308 X-Accept-Language: en-us, en MIME-Version: 1.0 To: george@mvista.com CC: Ingo Molnar , "linux-kernel@vger.kernel.org" , john stultz Subject: Re: [PATCH] to fix xtime lock for in the RT kernel patch References: <41F04573.7070508@mvista.com> <20050121063519.GA19954@elte.hu> <41F0BA56.9000605@mvista.com> <20050121082125.GA28267@elte.hu> <41F0BFA4.5030107@mvista.com> <20050121084557.GA29550@elte.hu> <41F0C33D.60908@mvista.com> <20050121090014.GA30379@elte.hu> <41F0C686.5070903@mvista.com> In-Reply-To: <41F0C686.5070903@mvista.com> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1632 Lines: 40 George Anzinger wrote: > Ingo Molnar wrote: > >> * George Anzinger wrote: >> >> >>> What I am suggesting is spliting the mark code so that it would only >>> grap the offset (current TSC in most systems) during interrupt >>> processing. Applying this would be done later in the thread. Since >>> it is not applying the offset, the xtime_lock would not need to be >>> taken. >> >> >> >> ok, you are right, and this would be fine with me. Wanna take a shot at >> it? I've uploaded the -03 patch which is my most current tree. (with the >> do_timer() moving done already.) I've reviewed the TSC offset codepath >> again and i'm not sure where i got the 10 usecs from ... it's a pretty >> cheap codepath that can be done in the direct interrupt just fine. >> > Tomorrow, uh, later today. Need some sleep now... Ingo, I have been looking at the code being proposed by John Stultz. It looks like it handles all the issues I am talking about here. I think it would be best to leave the RT patch as it is WRT this issue and work on getting John's patch ready for prime time as any work I would do here will just get tossed when his patch hits the steet. Meanwhile, I will (already have) get HRT working on RT and make that available in the next few days. -- George Anzinger george@mvista.com High-res-timers: http://sourceforge.net/projects/high-res-timers/ - 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/