Messages in this thread | | | Date | Tue, 13 Oct 2009 11:13:15 +0900 | From | Tejun Heo <> | Subject | Re: [this_cpu_xx V6 3/7] Use this_cpu operations in slub |
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Christoph Lameter wrote: > On Mon, 12 Oct 2009, Tejun Heo wrote: > >>> - c = get_cpu_slab(s, smp_processor_id()); >>> + c = __this_cpu_ptr(s->cpu_slab); >> Shouldn't this be this_cpu_ptr() without the double underscore? > > Interrupts are disabled so no concurrent fast path can occur. >
The only difference between this_cpu_ptr() and __this_cpu_ptr() is the usage of my_cpu_offset and __my_cpu_offset which in turn are only different in whether they check preemption status to make sure the cpu is pinned down when called.
The only places where the underbar prefixed versions should be used are places where cpu locality is nice but not critical and preemption debug check wouldn't work properly for whatever reason. The above is none of the two and the conversion is buried in a patch which is supposed to do something else. Am I missing something?
-- tejun
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