From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758468Ab3ANTbW (ORCPT ); Mon, 14 Jan 2013 14:31:22 -0500 Received: from g1t0026.austin.hp.com ([15.216.28.33]:13345 "EHLO g1t0026.austin.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757295Ab3ANTbU (ORCPT ); Mon, 14 Jan 2013 14:31:20 -0500 Message-ID: <1358191290.14145.88.camel@misato.fc.hp.com> Subject: Re: [RFC PATCH v2 02/12] ACPI: Add sys_hotplug.h for system device hotplug framework From: Toshi Kani To: "Rafael J. Wysocki" Cc: lenb@kernel.org, gregkh@linuxfoundation.org, akpm@linux-foundation.org, linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, bhelgaas@google.com, isimatu.yasuaki@jp.fujitsu.com, jiang.liu@huawei.com, wency@cn.fujitsu.com, guohanjun@huawei.com, yinghai@kernel.org, srivatsa.bhat@linux.vnet.ibm.com Date: Mon, 14 Jan 2013 12:21:30 -0700 In-Reply-To: <4116384.4pypaK248y@vostro.rjw.lan> References: <1357861230-29549-1-git-send-email-toshi.kani@hp.com> <3236298.SULt2IKQv6@vostro.rjw.lan> <1358188929.14145.69.camel@misato.fc.hp.com> <4116384.4pypaK248y@vostro.rjw.lan> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.4.4 (3.4.4-2.fc17) Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 2013-01-14 at 20:07 +0100, Rafael J. Wysocki wrote: > On Monday, January 14, 2013 11:42:09 AM Toshi Kani wrote: > > On Mon, 2013-01-14 at 19:47 +0100, Rafael J. Wysocki wrote: > > > On Monday, January 14, 2013 08:53:53 AM Toshi Kani wrote: > > > > On Fri, 2013-01-11 at 22:25 +0100, Rafael J. Wysocki wrote: > > > > > On Thursday, January 10, 2013 04:40:20 PM Toshi Kani wrote: > > > > > > Added include/acpi/sys_hotplug.h, which is ACPI-specific system > > > > > > device hotplug header and defines the order values of ACPI-specific > > > > > > handlers. > > > > > > > > > > > > Signed-off-by: Toshi Kani > > > > > > --- > > > > > > include/acpi/sys_hotplug.h | 48 ++++++++++++++++++++++++++++++++++++++++++++ > > > > > > 1 file changed, 48 insertions(+) > > > > > > create mode 100644 include/acpi/sys_hotplug.h > > > > > > > > > > > > diff --git a/include/acpi/sys_hotplug.h b/include/acpi/sys_hotplug.h > > > > > > new file mode 100644 > > > > > > index 0000000..ad80f61 > > > > > > --- /dev/null > > > > > > +++ b/include/acpi/sys_hotplug.h > > > > > > @@ -0,0 +1,48 @@ > > > > > > +/* > > > > > > + * sys_hotplug.h - ACPI System device hot-plug framework > > > > > > + * > > > > > > + * Copyright (C) 2012 Hewlett-Packard Development Company, L.P. > > > > > > + * Toshi Kani > > > > > > + * > > > > > > + * This program is free software; you can redistribute it and/or modify > > > > > > + * it under the terms of the GNU General Public License version 2 as > > > > > > + * published by the Free Software Foundation. > > > > > > + */ > > > > > > + > > > > > > +#ifndef _ACPI_SYS_HOTPLUG_H > > > > > > +#define _ACPI_SYS_HOTPLUG_H > > > > > > + > > > > > > +#include > > > > > > +#include > > > > > > +#include > > > > > > + > > > > > > +/* > > > > > > + * System device hot-plug operation proceeds in the following order. > > > > > > + * Validate phase -> Execute phase -> Commit phase > > > > > > + * > > > > > > + * The order values below define the calling sequence of ACPI-specific > > > > > > + * handlers for each phase in ascending order. The order value of > > > > > > + * platform-neutral handlers are defined in . > > > > > > + */ > > > > > > + > > > > > > +/* Add Validate order values */ > > > > > > +#define SHP_ACPI_BUS_ADD_VALIDATE_ORDER 0 /* must be first */ > > > > > > + > > > > > > +/* Add Execute order values */ > > > > > > +#define SHP_ACPI_BUS_ADD_EXECUTE_ORDER 10 > > > > > > +#define SHP_ACPI_RES_ADD_EXECUTE_ORDER 20 > > > > > > + > > > > > > +/* Add Commit order values */ > > > > > > +#define SHP_ACPI_BUS_ADD_COMMIT_ORDER 10 > > > > > > + > > > > > > +/* Delete Validate order values */ > > > > > > +#define SHP_ACPI_BUS_DEL_VALIDATE_ORDER 0 /* must be first */ > > > > > > +#define SHP_ACPI_RES_DEL_VALIDATE_ORDER 10 > > > > > > + > > > > > > +/* Delete Execute order values */ > > > > > > +#define SHP_ACPI_BUS_DEL_EXECUTE_ORDER 100 > > > > > > + > > > > > > +/* Delete Commit order values */ > > > > > > +#define SHP_ACPI_BUS_DEL_COMMIT_ORDER 100 > > > > > > + > > > > > > +#endif /* _ACPI_SYS_HOTPLUG_H */ > > > > > > -- > > > > > > > > > > Why did you use the particular values above? > > > > > > > > The ordering values above are used to define the relative order among > > > > handlers. For instance, the 100 for SHP_ACPI_BUS_DEL_EXECUTE_ORDER can > > > > potentially be 21 since it is still larger than 20 for > > > > SHP_MEM_DEL_EXECUTE_ORDER defined in linux/sys_hotplug.h. I picked 100 > > > > so that more platform-neutral handlers can be added in between 20 and > > > > 100 in future. > > > > > > I thought so, but I don't think it's a good idea to add gaps like this. > > > > OK, I will use an equal gap of 10 for all values. So, the 100 in the > > above example will be changed to 30. > > I wonder why you want to have those gaps at all. Oh, I see. I think some gap is helpful since it allows a new handler to come between without recompiling other modules. For instance, OEM vendors may want to add their own handlers with loadable modules after the kernel is distributed. > Anyway, this is just a small detail and it doesn't mean I don't have more > comments. I just need some more time to get the big picture idea of how this > is supposed to work and perhaps Greg will have some remarks too. Yes, I am well-aware of that. :-) Please let me know if you have any questions. I'd be happy to explain any details. Thanks a lot for reviewing! -Toshi