Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932275AbVIEHhm (ORCPT ); Mon, 5 Sep 2005 03:37:42 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932276AbVIEHhm (ORCPT ); Mon, 5 Sep 2005 03:37:42 -0400 Received: from caramon.arm.linux.org.uk ([212.18.232.186]:44306 "EHLO caramon.arm.linux.org.uk") by vger.kernel.org with ESMTP id S932275AbVIEHhl (ORCPT ); Mon, 5 Sep 2005 03:37:41 -0400 Date: Mon, 5 Sep 2005 08:37:28 +0100 From: Russell King To: Srivatsa Vaddagiri Cc: Nishanth Aravamudan , Con Kolivas , linux-kernel@vger.kernel.org, akpm@osdl.org, ck list Subject: Re: [PATCH 1/3] dynticks - implement no idle hz for x86 Message-ID: <20050905083728.A24051@flint.arm.linux.org.uk> Mail-Followup-To: Srivatsa Vaddagiri , Nishanth Aravamudan , Con Kolivas , linux-kernel@vger.kernel.org, akpm@osdl.org, ck list References: <20050831165843.GA4974@in.ibm.com> <200509031801.09069.kernel@kolivas.org> <20050903090650.B26998@flint.arm.linux.org.uk> <200509031814.49666.kernel@kolivas.org> <20050904201054.GA4495@us.ibm.com> <20050904212616.B11265@flint.arm.linux.org.uk> <20050905053225.GA4294@in.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5.1i In-Reply-To: <20050905053225.GA4294@in.ibm.com>; from vatsa@in.ibm.com on Mon, Sep 05, 2005 at 11:02:25AM +0530 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1245 Lines: 29 On Mon, Sep 05, 2005 at 11:02:25AM +0530, Srivatsa Vaddagiri wrote: > I don't see provisions for all these in the current ARM implementation. That's because, like x86, we've been ignoring each other. ARM doesn't handle dyntick SMP yet - ARM is fairly young as far as SMP issues goes, and as yet doesn't include a full SMP implementation in mainline. Despite that, the timers as implemented on the hardware are not suitable for dyntick use - attempting to use them, you lose long term precision of the timer interrupts. > 5. Don't see how DYN_TICK_SKIPPING is being used. In SMP scenario, > it doesnt make sense since it will have to be per-cpu. The bitmap > that I talked of exactly tells that (whether a CPU is skipping > ticks or not). What's DYN_TICK_SKIPPING and what's it used for? It looks like a redundant definition left over from Tony's original implementation. -- Russell King Linux kernel 2.6 ARM Linux - http://www.arm.linux.org.uk/ maintainer of: 2.6 Serial core - 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/