From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx193.postini.com [74.125.245.193]) by kanga.kvack.org (Postfix) with SMTP id A28236B0007 for ; Wed, 30 Jan 2013 20:48:35 -0500 (EST) Message-ID: <1359596310.15120.102.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 Date: Wed, 30 Jan 2013 18:38:30 -0700 In-Reply-To: <20130130045153.GE30002@kroah.com> 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> <1358191290.14145.88.camel@misato.fc.hp.com> <20130130045153.GE30002@kroah.com> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Greg KH Cc: "Rafael J. Wysocki" , lenb@kernel.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 On Tue, 2013-01-29 at 23:51 -0500, Greg KH wrote: > On Mon, Jan 14, 2013 at 12:21:30PM -0700, Toshi Kani wrote: > > 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. > > No, we don't support such a model, sorry, just make it a sequence of > numbers and go from there. If a vendor wants to modify the kernel to > add new values, they can rebuild the core code as well. > > I really don't like the whole idea of values in the first place, can't > we just do things in the correct order in the code, and not be driven by > random magic values? OK, I will define all the values with enum, which is something like below. I think it is more manageable in this way as we do not have to define magic values. enum shp_add_order { /* Validate Phase */ SHP_FW_BUS_ADD_VALIDATE_ORDER, /* Execute Phase */ SHP_FW_BUS_ADD_EXECUTE_ORDER, SHP_FW_RES_ADD_EXECUTE_ORDER, SHP_MEM_ADD_EXECUTE_ORDER, SHP_CPU_ADD_EXECUTE_ORDER, /* Commit Phase */ SHP_ADD_COMMIT_BASE_ORDER, SHP_FW_BUS_ADD_COMMIT_ORDER, }; Thanks, -Toshi -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org