Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755095AbZLNBIi (ORCPT ); Sun, 13 Dec 2009 20:08:38 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755555AbZLNBIe (ORCPT ); Sun, 13 Dec 2009 20:08:34 -0500 Received: from mga14.intel.com ([143.182.124.37]:43643 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755366AbZLNBIc (ORCPT ); Sun, 13 Dec 2009 20:08:32 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.47,316,1257148800"; d="scan'208";a="222369833" Date: Mon, 14 Dec 2009 09:08:29 +0800 From: Shaohua Li To: Andrew Morton Cc: "linux-kernel@vger.kernel.org" , "linux-acpi@vger.kernel.org" , "lenb@kernel.org" , "mingo@elte.hu" Subject: Re: [PATCH 2/2]ACPI: assign different lockdep key for acpi works Message-ID: <20091214010829.GA11436@sli10-desk.sh.intel.com> References: <20091211030458.GB7772@sli10-desk.sh.intel.com> <20091211135716.b6d577a1.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20091211135716.b6d577a1.akpm@linux-foundation.org> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2821 Lines: 70 On Sat, Dec 12, 2009 at 05:57:16AM +0800, Andrew Morton wrote: > On Fri, 11 Dec 2009 11:04:58 +0800 > Shaohua Li wrote: > > > Differentiate works for three different workqueue in ACPI. This fixes > > a fase alarm from lockdep, as acpi hotplug workqueue waits other > > workqueues. > > > > http://bugzilla.kernel.org/show_bug.cgi?id=14553 > > > > Signed-off-by: Shaohua Li > > --- > > drivers/acpi/osl.c | 12 +++++++++++- > > 1 file changed, 11 insertions(+), 1 deletion(-) > > > > Index: linux/drivers/acpi/osl.c > > =================================================================== > > --- linux.orig/drivers/acpi/osl.c 2009-12-10 10:40:15.000000000 +0800 > > +++ linux/drivers/acpi/osl.c 2009-12-10 10:43:25.000000000 +0800 > > @@ -729,6 +729,8 @@ static acpi_status __acpi_os_execute(acp > > struct acpi_os_dpc *dpc; > > struct workqueue_struct *queue; > > int ret; > > + static struct lock_class_key hp_key, notify_key, acpid_key; > > + > > ACPI_DEBUG_PRINT((ACPI_DB_EXEC, > > "Scheduling function [%p(%p)] for deferred execution.\n", > > function, context)); > > @@ -758,7 +760,15 @@ static acpi_status __acpi_os_execute(acp > > queue = hp ? kacpi_hotplug_wq : > > (type == OSL_NOTIFY_HANDLER ? kacpi_notify_wq : kacpid_wq); > > dpc->wait = hp ? 1 : 0; > > - INIT_WORK(&dpc->work, acpi_os_execute_deferred); > > + if (queue == kacpi_hotplug_wq) > > + INIT_WORK_KEY(&dpc->work, acpi_os_execute_deferred, > > + hp_key, "acpi_hp_work"); > > + else if (queue == kacpi_notify_wq) > > + INIT_WORK_KEY(&dpc->work, acpi_os_execute_deferred, > > + notify_key, "acpi_notify_work"); > > + else > > + INIT_WORK_KEY(&dpc->work, acpi_os_execute_deferred, > > + acpid_key, "acpi_acpid_work"); > > ret = queue_work(queue, &dpc->work); > > > > if (!ret) { > > Yes, that's a shortcoming in the present INIT_WORK(). However I think > you can solve this more simply, without introducing INIT_WORK_KEY(): > > if (queue == kacpi_hotplug_wq) > INIT_WORK(&dpc->work, acpi_os_execute_deferred); > else if (queue == kacpi_notify_wq) > INIT_WORK(&dpc->work, acpi_os_execute_deferred); > else > INIT_WORK(&dpc->work, acpi_os_execute_deferred); > > it looks silly, but I think the compiler will do the right thing with it > - you'll get a separate lock_class_key at each site. > > Obviously it would need an explanatory comment. Yes, I tried this way before, it centainly works. I just thought maybe others need similar API. If I'm over thinking, let's take your way. Thanks, Shaohua -- 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/