Re: lockdep oddity

[Ingo Molnar]

* Hua Zhong <hzhong@xxxxxxxxx> wrote:

> We are just trading accuracy for speed here.

no, we are trading _both_ accuracy and speed here! a global 'likeliness' 
pointer for commonly executed codepaths is causing global cacheline 
ping-pongs - which is as bad as it gets.

the right approach, which incidentally would also be perfectly accurate, 
is to store an alloc_percpu()-ed pointer at the call site, not the 
counter itself.

the current code needs more work before it can go upstream i think.

	Ingo
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