Re: [patch] Real-Time Preemption, plist fixes

[Ingo Molnar]

* Thomas Gleixner <tglx@xxxxxxxxxxxxx> wrote:

> + * (C) 2005 Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> + * Tested and made it functional. I'm still pondering if it is
> + * worth the trouble.

you had a long Saturday night debugging session i guess:

> Date: Sun, 05 Jun 2005 02:17:12 +0200

but i think the fundamental question remains even on Sunday mornings -
is the plist overhead worth it? Compared to the simple sorted list we 
exchange O(nr_RT_tasks_running) for O(nr_RT_levels_used) [which is in 
the 1-100 range], is that a significant practical improvement? By 
overhead i dont just mean cycle cost, but also architectural flexibility 
and maintainability.

in any case, i've added most of your fixes and cleanups (changed the
O(N) to O(K) and explained K) and have released the -47-17 patch.
Daniel, do agree with these changes (in particular the __plist_del()
changes?) and is there anything else missing? It looks like we might be
near the end of the tunnel and plists are really stabilizing.

	Ingo
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