Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761322Ab2KAXjy (ORCPT ); Thu, 1 Nov 2012 19:39:54 -0400 Received: from mail-wi0-f172.google.com ([209.85.212.172]:41424 "EHLO mail-wi0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756360Ab2KAXjw (ORCPT ); Thu, 1 Nov 2012 19:39:52 -0400 MIME-Version: 1.0 In-Reply-To: <1920067.RxMJtDGai1@vostro.rjw.lan> References: <1351668471-31436-1-git-send-email-tangchen@cn.fujitsu.com> <11976302.Ya3MGGIAsU@vostro.rjw.lan> <1920067.RxMJtDGai1@vostro.rjw.lan> Date: Thu, 1 Nov 2012 16:39:50 -0700 X-Google-Sender-Auth: A6wsdj6QXmbwvs3kEG5OTEF79Xg Message-ID: Subject: Re: [PATCH v3 3/3] Improve container_notify_cb() to support container hot-remove. From: Yinghai Lu To: "Rafael J. Wysocki" Cc: Toshi Kani , ZhangRui , Andrew Morton , Len Brown , Tang Chen , bhelgaas@google.com, jiang.liu@huawei.com, izumi.taku@jp.fujitsu.com, isimatu.yasuaki@jp.fujitsu.com, linux-acpi@vger.kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2662 Lines: 70 On Thu, Nov 1, 2012 at 4:15 PM, Rafael J. Wysocki wrote: > From: Rafael J. Wysocki > Subject: ACPI: Make seemingly useless check in osl.c more understandable > > There is a seemingly useless check in drivers/acpi/osl.c added by > commit bc73675 (ACPI: fixes a false alarm from lockdep), which really > is necessary to avoid false positive lockdep complaints. Document > this and rearrange the code related to it so that it makes fewer > checks. > > Signed-off-by: Rafael J. Wysocki > --- > drivers/acpi/osl.c | 21 ++++++++++++++------- > 1 file changed, 14 insertions(+), 7 deletions(-) > > Index: linux/drivers/acpi/osl.c > =================================================================== > --- linux.orig/drivers/acpi/osl.c > +++ linux/drivers/acpi/osl.c > @@ -944,17 +944,24 @@ static acpi_status __acpi_os_execute(acp > * because the hotplug code may call driver .remove() functions, > * which invoke flush_scheduled_work/acpi_os_wait_events_complete > * to flush these workqueues. > + * > + * To prevent lockdep from complaining unnecessarily, make sure that > + * there is a different static lockdep key for each workqueue by using > + * INIT_WORK() for each of them separately. > */ > - queue = hp ? kacpi_hotplug_wq : > - (type == OSL_NOTIFY_HANDLER ? kacpi_notify_wq : kacpid_wq); > - dpc->wait = hp ? 1 : 0; > - > - if (queue == kacpi_hotplug_wq) > + if (hp) { > + queue = kacpi_hotplug_wq; > + dpc->wait = 1; > INIT_WORK(&dpc->work, acpi_os_execute_deferred); > - else if (queue == kacpi_notify_wq) > + } else if (type == OSL_NOTIFY_HANDLER) { > + queue = kacpi_notify_wq; > + dpc->wait = 0; yes, much clear. at the same can you changne dpc allocation from kmalloc with kzalloc instead. then we save two lines for dpc->wait = 0 After that Acked-by: Yinghai Lu > INIT_WORK(&dpc->work, acpi_os_execute_deferred); > - else > + } else { > + queue = kacpid_wq; > + dpc->wait = 0; > INIT_WORK(&dpc->work, acpi_os_execute_deferred); > + } > > /* > * On some machines, a software-initiated SMI causes corruption unless > > -- -- 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/