Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752476AbZIQUIh (ORCPT ); Thu, 17 Sep 2009 16:08:37 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751923AbZIQUIf (ORCPT ); Thu, 17 Sep 2009 16:08:35 -0400 Received: from astoria.ccjclearline.com ([64.235.106.9]:51172 "EHLO astoria.ccjclearline.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751769AbZIQUIf (ORCPT ); Thu, 17 Sep 2009 16:08:35 -0400 Date: Thu, 17 Sep 2009 16:08:32 -0400 (EDT) From: "Robert P. J. Day" X-X-Sender: rpjday@localhost To: Cyrill Gorcunov cc: Linux Kernel Mailing List , Thomas Gleixner Subject: Re: test for "spurious" IRQ ignores possible IRQ_WAKE_THREAD value In-Reply-To: <20090917193416.GE8817@lenovo> Message-ID: References: <20090917193416.GE8817@lenovo> User-Agent: Alpine 2.00 (LFD 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - astoria.ccjclearline.com X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - crashcourse.ca X-Source: X-Source-Args: X-Source-Dir: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2587 Lines: 75 On Thu, 17 Sep 2009, Cyrill Gorcunov wrote: > [Robert P. J. Day - Mon, Sep 14, 2009 at 04:34:48PM -0400] > | On Mon, 14 Sep 2009, Robert P. J. Day wrote: > | > | > never ashamed to embarrass myself in public, i just noticed the > | > following. from kernel/irq/spurious.c: > | > > | > ... > | > static void > | > __report_bad_irq(unsigned int irq, struct irq_desc *desc, > | > irqreturn_t action_ret) > | > { > | > struct irqaction *action; > | > > | > if (action_ret != IRQ_HANDLED && action_ret != IRQ_NONE) { > | > printk(KERN_ERR "irq event %d: bogus return value %x\n", > | > irq, action_ret); > | > > | > but from include/linux/irqreturn.h, we see *three* possible return > | > values: > | > > | > enum irqreturn { > | > IRQ_NONE, > | > IRQ_HANDLED, > | > IRQ_WAKE_THREAD, > | > }; > | > > | > typedef enum irqreturn irqreturn_t; > | > #define IRQ_RETVAL(x) ((x) != IRQ_NONE) > | > > | > is there an inconsistency here? > | > ... > > Hi Robert, > > It could that IRQ_WAKE_THREAD is just missed here. I suppose it was > brough there as thread irq merged. But I think only Thomas know for > sure, I definitely miss something :) CC'ed actually, after a bit more reading, i found this in kernel/irq/handle.c: ... switch (ret) { case IRQ_WAKE_THREAD: /* * Set result to handled so the spurious check * does not trigger. */ ret = IRQ_HANDLED; ... so it looks like that value of IRQ_WAKE_THREAD is simply "mapped" to IRQ_HANDLED, and perhaps that's done before __report_bad_irq is ever called so that that latter routine never sees a value of IRQ_WAKE_THREAD. but that's just a guess. rday -- ======================================================================== Robert P. J. Day Waterloo, Ontario, CANADA Linux Consulting, Training and Annoying Kernel Pedantry. Web page: http://crashcourse.ca Twitter: http://twitter.com/rpjday ======================================================================== -- 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/