Re: [markgross@thengar.org: [RFC] wake up notifications and suspendblocking (aka more wakelock stuff)]

[Alan Stern]

On Thu, 13 Oct 2011, NeilBrown wrote:

> Nope, but I'm keen for you to convince me.  Identify a wakeup event that
> cannot be made visible to poll (or to user-space by some other
> mechanism) before the wakeup_source needs to be deactivated.  Or if I've
> misunderstood what sort of notification is problematic, help me understand.

Here's an example (just for kicks, not completely relevant to your
discussion): A USB keyboard key release.  Unlike key presses, key
releases need not generate input events.  If no processes are
monitoring the raw keyboard event queue then the release is not visible
to userspace at all, hence not visible before the wakeup_source needs
to be deactivated.

Alan Stern

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