From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Renninger Subject: Re: [PATCH 01/10] ACPI: support acpi_device_ops .notify methods Date: Fri, 3 Apr 2009 11:08:06 +0200 Message-ID: <200904031108.09572.trenn@suse.de> References: <200904021556.32810.trenn@suse.de> <200904020903.21140.bjorn.helgaas@hp.com> <20090403090717.B9BE.E1E9C6FF@jp.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Return-path: Received: from cantor2.suse.de ([195.135.220.15]:33645 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751964AbZDCJIT (ORCPT ); Fri, 3 Apr 2009 05:08:19 -0400 In-Reply-To: <20090403090717.B9BE.E1E9C6FF@jp.fujitsu.com> Content-Disposition: inline Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Yasunori Goto Cc: Bjorn Helgaas , kamezawa.hiroyu@jp.fujitsu.com, Len Brown , Tony Vroon , Alex Chiang , linux-acpi@vger.kernel.org, Carlos Corbacho , Anil S Keshavamurthy , Jonathan Woithe , Zhao Yakui , Mattia Dongili , Harald Welte , Venki Pallipadi , Alexey Starikovskiy , Zhang Rui , Matthew Garrett On Friday 03 April 2009 02:23:16 Yasunori Goto wrote: > > On Thursday 02 April 2009 07:56:28 am Thomas Renninger wrote: > > > On Monday 30 March 2009 19:48:13 Bjorn Helgaas wrote: > > > > This patch adds support for ACPI device driver .notify() methods. If > > > > such a method is present, Linux/ACPI installs a handler for device > > > > notifications (but not for system notifications such as Bus Check, > > > > Device Check, etc). When a device notification occurs, Linux/ACPI > > > > passes it on to the driver's .notify() method. > > > I sent more or less the same some years ago. > > > Thanks a lot for finally cleaning this up! > > > > Hi Thomas, > > > > Oh, sorry, I didn't know that, or I would have given you some credit :-) > > In fact, if you have a URL, I'll add a pointer to the changelog. I > > always like to leave breadcrumbs to help future research. > > > > > > Several drivers install their own handlers for system Bus Check and > > > > Device Check notifications so they can support hot-plug. This patch > > > > doesn't affect that usage. > > > Getting rid of these will be the tricky part. > > > When I looked at it start/stop already was defined, but nobody used it. > > > IMO start/stop is not needed and hotplug capable device drivers can > > > handle things themselves in the relevant notify case. > > > > I'd really like to get rid of the bus/device check notification stuff > > in the drivers eventually. IMHO, the core Linux/ACPI code should > > field those notifications and just call the driver .add() and .remove() > > methods as necessary. > > > > But you're right, it's going to be quite tricky. I'm looking at getting > > rid of .start() right now, because that's a major complication. The > > biggest user looks like acpiphp, and that is going to be a mess to > > straighten out. > > > > > I remember these two guys helped me testing on memory hotplug. > > > They only had a simulator, but might want to give the latest kernel a try if > > > you come to clean up acpi_memhotplug.c: > > > kamezawa.hiroyu@jp.fujitsu.com > > > Yasunori Goto > > I can use real machine which can memory hotplug. > In our case, notify method is called for container device (NUMA node), > and memory and processor devices are added under acpi_bus_scan(). > > I'll book it to test this patch in next week. > It must be good test. :-) Better wait a bit or ask Bjorn. I expect this is only the beginning of his cleanups and the tricky parts will still come. Thanks, Thomas