Messages in this thread | | | Date | Sat, 15 May 2004 04:59:54 +0200 | From | Pavel Machek <> | Subject | Re: Hotplug events for system suspend/resume |
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Hi!
> >I still do not see the need for this. As a user, you caused the > >suspend/resume event to happen, why get notified of it again? :) > > The idea is to notify the "power management application" of impending > suspend and just-completed resume, regardless of who or what asked for > the suspend. Actions taken at suspend might include dropping network > connections and saving application state to stable storage. > > The reasons for which this was requested of me as a kernel-to-userspace > notifier, that I am aware of, are: > > (a) some embedded platforms currently trigger suspend within kernel > drivers (in response to a button press or some sort of device >timeout).
I believe kernel should userspace "button was pressed", and let userspace ask it for suspend.
> (b) the system designer wants to make sure certain actions are always > taken regardless of the interface used to suspend (not only in the case > of a certain application that incorporates these actions and triggers > the suspend via the standard interfaces at the appropriate time). For > example, a user manually enters a command from a shell prompt.
User should not manually do "echo something > /proc/acpi/sleep". For embedded platforms, it should be rather easy to ensure user does not do that, right?
OTOH, it might make sense to define that /etc/rc.d/suspend/* has to be run before suspend and /etc/rc.d/resume/* has to be run after suspend; by whoever who does suspend.
suspend-vetoing is pretty bad idea if your battery is running down. I believe shutdown does it right: kill -15 -1; sleep 1; kill -9 -1. I.e. let apps know one second before suspend, but do not let them veto it. Pavel -- When do you have heart between your knees? - 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/
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