Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758788AbXERFF4 (ORCPT ); Fri, 18 May 2007 01:05:56 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755179AbXERFFs (ORCPT ); Fri, 18 May 2007 01:05:48 -0400 Received: from gate.crashing.org ([63.228.1.57]:56038 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755107AbXERFFs (ORCPT ); Fri, 18 May 2007 01:05:48 -0400 Subject: Re: [PATCH 2.6.21-rt2] PowerPC: decrementer clockevent driver From: Benjamin Herrenschmidt To: Segher Boessenkool Cc: Sergei Shtylyov , linuxppc-dev@ozlabs.org, tglx@linutronix.de, mingo@elte.hu, linux-kernel@vger.kernel.org In-Reply-To: <97d47c2261fe9cd3f1a6c864278a6ab6@kernel.crashing.org> References: <200705172142.26739.sshtylyov@ru.mvista.com> <464CB071.5050504@ru.mvista.com> <9095839480a9686d9c40aa6143edb804@kernel.crashing.org> <464CB460.40905@ru.mvista.com> <97d47c2261fe9cd3f1a6c864278a6ab6@kernel.crashing.org> Content-Type: text/plain Date: Fri, 18 May 2007 15:04:49 +1000 Message-Id: <1179464690.32247.370.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Evolution 2.10.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 706 Lines: 19 > > Yes, on some implementations there can be other conditions that > make a decrementer exception go away; there is no contradiction > here (thankfully). My wording was sloppy. Some CPUs have the DEC exceptions basically edge triggered (yeah I know it sucks). That's why, among others, the IRQ soft-disable code has code to re-trigger DEC exceptions ASAP (by setting it to 1.. note that we could probably use 0 here, we've been a bit conservative). Ben. - 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/