Re: #tj-percpu has been rebased

["H. Peter Anvin" <hpa@zytor.com>]

Rusty Russell wrote:
>>>
>> num_possible_cpus() can be very large though, so in many cases the
>> likelihood of finding that many pages approach zero.  Furthermore,
>> num_possible_cpus() may be quite a bit larger than the actual number of
>> CPUs in the system.
> 
> Sure, so we end up at vmalloc.  No worse, but simpler and much better if we
> *can* do it.
> 

If the likelihood is near zero, then you're wasting opportunities to do
it better.  If we have compact per-cpu virtual areas then we can use
large pages if we know we'll have large percpu areas.

	-hpa

-- 
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel.  I don't speak on their behalf.