Re: [PATCH 06/10] x86: reduce memory and stack usage in intel_cacheinfo

[H. Peter Anvin]

Ingo Molnar wrote:
> > The main goal was to avoid allocating 4096 bytes when only 32 would do 
> > (characters needed to represent nr_cpu_ids cpus instead of NR_CPUS 
> > cpus.) But I'll look at cleaning it up a bit more.  It wouldn't have 
> > to be a function if CHUNKSZ in cpumask_scnprintf() were visible (or a 
> > non-changeable constant.)
>
> well, do we care about allocating 4096 bytes, as long as we also free 
> it? It's not like we need to clear all the bytes or something. Am i 
> missing something here?

Well, 32 bytes fits on the stack, whereas 4096 bytes requires allocating 
a page -- which means either taking the risk of failing or blocking.  Of 
course, we're doing this for output, which has the same issue.

	-hpa
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