From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752995AbbBKOIO (ORCPT ); Wed, 11 Feb 2015 09:08:14 -0500 Received: from v094114.home.net.pl ([79.96.170.134]:51340 "HELO v094114.home.net.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1752576AbbBKOIN (ORCPT ); Wed, 11 Feb 2015 09:08:13 -0500 From: "Rafael J. Wysocki" To: Mark Rutland Cc: Peter Zijlstra , Boris Brezillon , Thomas Gleixner , Jason Cooper , Nicolas Ferre , Jean-Christophe Plagniol-Villard , Alexandre Belloni , Rob Herring , Pawel Moll , Ian Campbell , Kumar Gala , "devicetree@vger.kernel.org" , "Rafael J. Wysocki" , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH v4 3/5] irqchip: Add DT binding doc for the virtual irq demuxer chip Date: Wed, 11 Feb 2015 15:31:18 +0100 Message-ID: <32372622.IiYZ15O7e1@vostro.rjw.lan> User-Agent: KMail/4.11.5 (Linux/3.16.0-rc5+; KDE/4.11.5; x86_64; ; ) In-Reply-To: <20150211111516.GB9154@leverpostej> References: <1422527620-8308-1-git-send-email-boris.brezillon@free-electrons.com> <20150211091159.GE7119@twins.programming.kicks-ass.net> <20150211111516.GB9154@leverpostej> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="utf-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wednesday, February 11, 2015 11:15:17 AM Mark Rutland wrote: > On Wed, Feb 11, 2015 at 09:11:59AM +0000, Peter Zijlstra wrote: > > On Tue, Feb 10, 2015 at 08:48:36PM +0000, Mark Rutland wrote: > > > From f390ccbb31f06efee49b4469943c8d85d963bfb5 Mon Sep 17 00:00:00 2001 > > > From: Mark Rutland > > > Date: Tue, 10 Feb 2015 20:14:33 +0000 > > > Subject: [PATCH] genirq: allow mixed IRQF_NO_SUSPEND requests > > > > > > In some cases a physical IRQ line may be shared between devices from > > > which we expect interrupts during suspend (e.g. timers) and those we do > > > not (e.g. anything we cut the power to). Where a driver did not request > > > the interrupt with IRQF_NO_SUSPEND, it's unlikely that it can handle > > > being called during suspend, and it may bring down the system. > > > > > > This patch adds logic to automatically mark the irqactions for these > > > potentially unsafe handlers as disabled during suspend, leaving actions > > > with IRQF_NO_SUSPEND enabled. If an interrupt is raised on a shared line > > > during suspend, only the handlers requested with IRQF_NO_SUSPEND will be > > > called. The handlers requested without IRQF_NO_SUSPEND will be skipped > > > as if they had immediately returned IRQF_NONE. > > > > > > Cc: Boris Brezillon > > > Cc: Jason Cooper > > > Cc: Nicolas Ferre > > > Cc: Peter Zijlstra > > > Cc: Rafael J. Wysocki > > > Cc: Thomas Gleixner > > > Signed-off-by: Mark Rutland > > > > Aw gawd.. not that again. > > I agree this isn't pretty, but at least it doesn't require the HW > description to know about Linux internals, and it can work for !DT > systems. > > I'm really not happy with placing Linux implementation details into > DTBs. > > > So Rafael and tglx went over this a few months ago I think: > > > > lkml.kernel.org/r/26580319.OZP7jvJnA9@vostro.rjw.lan > > > > is the last series I could find. Maybe Rafael can summarize? > > I can't get at any commentary from that link, unfortunately. > > Rafael? Well, the commentary is not there, because both I and Thomas implicitly agreed on one thing: We cannot add any suspend-related checks to the interrupt handling hot path, because that will affect everyone including people who don't use suspend at all and who *really* care about interrupt handling performance. Rafael