From mboxrd@z Thu Jan 1 00:00:00 1970 From: Benjamin Herrenschmidt Subject: Re: suspend.c vs driver-model.txt Date: Tue, 30 Jul 2002 20:27:38 +0200 Sender: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Message-ID: <20020730182738.25937@192.168.4.1> References: <20020730190041.GH7567@atrey.karlin.mff.cuni.cz> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20020730190041.GH7567-jyMamyUUXNJG4ohzP4jBZS1Fcj925eT/@public.gmane.org> Errors-To: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Help: List-Post: List-Subscribe: , List-Unsubscribe: , List-Archive: To: Pavel Machek , Patrick Mochel Cc: acpi-devel-pyega4qmqnRoyOMFzWx49A@public.gmane.org List-Id: linux-acpi@vger.kernel.org >Benjamin Herrenschmidt was arguing for doing driver_suspend() while >userspace is still running. If you assumed stopped userspace, you >don't have to add semaphore into device read() etc... And stopping any kernel thread that may do that etc... I really don't like it that much, but well, it can be a working solution for 2.6 for drivers having a direct userspace /dev interface. >> > 2) we are running with just one active CPU. >> >> Sure. We can tie that into subsystem notification, like this: >> >> - The level at which we want to stop requests appears to be at the device >> class level. >> >> - Device classes are coming RSN. >> >> - CPUs belong to a device class. >> >> - We can integrate PM notication into device classes. >> >> - The CPU device class can shut off all APs (application processors [silly >> Intel term]). > >I believe shutting down CPUs should be done outside device_suspend() >so all device_suspends() run on just one CPU... That makes things easier, I tend to agree here. Ben. ------------------------------------------------------- This sf.net email is sponsored by: Dice - The leading online job board for high-tech professionals. Search and apply for tech jobs today! http://seeker.dice.com/seeker.epl?rel_code=31