From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935082AbYEBM5r (ORCPT ); Fri, 2 May 2008 08:57:47 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1759837AbYEBM5g (ORCPT ); Fri, 2 May 2008 08:57:36 -0400 Received: from mail.ocs.com.au ([203.34.248.175]:17718 "EHLO mail.ocs.com.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760364AbYEBM5f (ORCPT ); Fri, 2 May 2008 08:57:35 -0400 X-Greylist: delayed 406 seconds by postgrey-1.27 at vger.kernel.org; Fri, 02 May 2008 08:57:34 EDT X-Mailer: exmh version 2.7.2 01/07/2005 (debian 1:2.7.2-12) with nmh-1.2 From: Keith Owens To: paulmck@linux.vnet.ibm.com cc: Nick Piggin , Jens Axboe , linux-kernel@vger.kernel.org, peterz@infradead.org, linux-arch@vger.kernel.org, jeremy@goop.org, mingo@elte.hu Subject: Re: [PATCH 1/10] Add generic helpers for arch IPI function calls In-reply-to: Your message of "Fri, 02 May 2008 05:29:55 MST." <20080502122955.GB15522@linux.vnet.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Fri, 02 May 2008 22:50:44 +1000 Message-ID: <27854.1209732644@ocs10w> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org "Paul E. McKenney" (on Fri, 2 May 2008 05:29:55 -0700) wrote: >OK -- for some reason, I was thinking that it was illegal to >invoke smp_call_function() with irqs disabled... > >Ah, I see it -- smp_call_function_mask() says: > > * You must not call this function with disabled interrupts or from a > * hardware interrupt handler or from a bottom half handler. > >So we have no problem with smp_call_function, then. > >OK, so smp_call_function() -can- be invoked with irqs disabled? >Hmmm... I will give this some thought. Doing any smp_call_function with interrupts disabled is a potential deadlock. See http://lkml.org/lkml/2004/5/2/116.