Messages in this thread | | | Subject | Re: [PATCH] I3 sched tweaks... | From | Robert Love <> | Date | 16 Jan 2002 16:10:09 -0500 |
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On Wed, 2002-01-16 at 17:46, Ingo Molnar wrote:
> we pass pointers across functions regularly, even if the pointer could be > calculated within the function. We do this in the timer code too. It's > slightly cheaper to pass an already existing (calculated) 'current' > pointer over to another function, instead of calculating it once more in > that function. This will be especially true once we make 'current' a tiny > bit more expensive (Alan's kernel stack coloring rewrite will do that i > think, it will be one more instruction to get 'current'.)
Maybe we should benchmark it? It is very easy to calculate current.
Certainly I see the benefit if we start coloring the pointer (it adds 2 instructions I believe) but let's make sure it is worth passing another 32-bit argument. It could very well be, schedule_tick is called enough...
> > Moreover, the function doesn't make *sense* if p != current... > > yes - would it be perhaps cleaner then to name the variable 'this_task' or > something like that?
Yes, good idea.
Robert Love
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