Re: [PATCH -v5][RFC]: mutex: implement adaptive spinning

[Peter W. Morreale]

On Wed, 2009-01-07 at 23:33 +0100, Ingo Molnar wrote:
> * Gregory Haskins <ghaskins@xxxxxxxxxx> wrote:
> 
> > Can I ask a simple question in light of all this discussion?
> > 
> > "Is get_task_struct() really that bad?"
> 
> it dirties a cacheline and it also involves atomics.
> 
> Also, it's a small design cleanliness issue to me: get_task_struct() 
> impacts the lifetime of an object - and if a locking primitive has 
> side-effects on object lifetimes that's never nice.
> 

True, but it's for one iteration * NR_CPUS, max.

Best,
-PWM


> 	Ingo
> 

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