Re: [PATCH 2/13] Time: Reduced NTP Rework (part 2)

[Ingo Molnar]

* Ulrich Windl <ulrich.windl@xxxxxxxxxxxxxxxxxxxx> wrote:

> > I'm thinking about moving the leap second handling to a timer, with the 
> > new timer system it would be easy to set a timer for e.g. 23:59.59 and 
> > then set the time. This way it would be gone from the common path and it 
> > wouldn't matter that much anymore whether it's used or not.
> 
> Will the timer solution guarantee consistent and exact updates?

it would still be dependent on system-load situations. It's an 
interesting idea to use a timer for that, but there is no strict 
synchronization between "get time of day" and "timer execution", so any 
timer-based leap-second handling would be fundamentally asynchronous. I 
dont think we want that, leap second handling should be a synchronous 
property of 'time'.

i think the very first step should be the cleanups i did to the NTP 
portions of timer.c. That made all the code (including leap second 
handling) more readable. I think a portion of the inner desire to 
rewrite the NTP code comes from the current spaghetti that accumulated 
over the years.

	Ingo
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