From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S966209AbWKTRBz (ORCPT ); Mon, 20 Nov 2006 12:01:55 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S966210AbWKTRBz (ORCPT ); Mon, 20 Nov 2006 12:01:55 -0500 Received: from h155.mvista.com ([63.81.120.155]:16327 "EHLO imap.sh.mvista.com") by vger.kernel.org with ESMTP id S966207AbWKTRBy (ORCPT ); Mon, 20 Nov 2006 12:01:54 -0500 Message-ID: <4561DFE1.4020708@ru.mvista.com> Date: Mon, 20 Nov 2006 20:03:29 +0300 From: Sergei Shtylyov Organization: MontaVista Software Inc. User-Agent: Mozilla/5.0 (X11; U; Linux i686; rv:1.7.2) Gecko/20040803 X-Accept-Language: ru, en-us, en-gb MIME-Version: 1.0 To: Ingo Molnar Cc: Benjamin Herrenschmidt , linuxppc-dev@ozlabs.org, linux-kernel@vger.kernel.org, dwalker@mvista.com Subject: Re: [PATCH] 2.6.18-rt7: PowerPC: fix breakage in threaded fasteoi type IRQ handlers References: <200611192243.34850.sshtylyov@ru.mvista.com> <1163966437.5826.99.camel@localhost.localdomain> <20061119200650.GA22949@elte.hu> <1163967590.5826.104.camel@localhost.localdomain> <20061119202348.GA27649@elte.hu> <1163985380.5826.139.camel@localhost.localdomain> <20061120100144.GA27812@elte.hu> <4561C9EC.3020506@ru.mvista.com> <20061120165621.GA1504@elte.hu> In-Reply-To: <20061120165621.GA1504@elte.hu> 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 Hello. Ingo Molnar wrote: >>>on PPC64, 'get the vector' initiates an ACK as well - is that done >>>before handle_irq() is done? >> Exactly. How else do_IRQ() would know the vector? > the reason i'm asking is that in this case masking is a bit late at this > point and there's a chance for a repeat interrupt. How's that? Acknowledge != EOI on OpenPIC (as well as 8259). Acknoledging sets the bit in the in-service register preventing all the interrupts with same or lower prioriry from being accepted. > Ingo WBR, Sergei