Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754702AbYJBOqU (ORCPT ); Thu, 2 Oct 2008 10:46:20 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753580AbYJBOqM (ORCPT ); Thu, 2 Oct 2008 10:46:12 -0400 Received: from one.firstfloor.org ([213.235.205.2]:33370 "EHLO one.firstfloor.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752514AbYJBOqL (ORCPT ); Thu, 2 Oct 2008 10:46:11 -0400 To: Thomas Gleixner Cc: LKML , Linus Torvalds , Andrew Morton , Ingo Molnar , Arjan van de Veen , Benjamin Herrenschmidt , Steven Rostedt , Jon Masters , Sven Dietrich Subject: Re: [RFC patch 0/5] genirq: add infrastructure for threaded interrupt handlers From: Andi Kleen References: <20081001223213.078984344@linutronix.de> Date: Thu, 02 Oct 2008 16:46:09 +0200 In-Reply-To: <20081001223213.078984344@linutronix.de> (Thomas Gleixner's message of "Wed, 01 Oct 2008 23:02:08 -0000") Message-ID: <873ajfoy1a.fsf@basil.nowhere.org> User-Agent: Gnus/5.1008 (Gnus v5.10.8) Emacs/21.3 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1386 Lines: 41 Thomas Gleixner writes: > > - move long running handlers out of the hard interrupt context I'm not sure I'm really looking forward to this brave new world of very long running interrupt handlers. e.g. what do you do for example when some handler blocks for a very long time? > - improved debugability of the kernel: faulty handlers do not take > down the system. I had an old patch to handle this without threaded interrupts. What normally happens is when a interrupt oopses it tries to kill the idle process which panics. My fix was to just restart another idle process instead of panicing. But back then it was rejected by Linus with the argument that a crashing interrupt handler will typically hold some lock and the next time the interrupt happens it will deadlock on that lock. Has that changed with your threaded interrupts? If it has changed I suspect the restart idle change could be made to work to be equivalent in debuggability. > Comments, reviews, flames as usual. To be honest my opinion is that it will encourage badly written interrupt code longer term. -Andi -- ak@linux.intel.com -- 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/