Re: [PATCH 2/2] lockdep: check that no locks held at freeze time

[Linus Torvalds]

On Mon, May 6, 2013 at 1:55 AM, Peter Zijlstra <a.p.zijlstra@xxxxxxxxx> wrote:
>
> Doesn't i386 have all the funny per-cpu stuff too? So the only reason it still
> does the fugly stack based thing is because nobody could be arsed to do the
> work of converting it.

Umm. That "fugly stack-based" thing is better than the per-cpu crap.

The percpu stuff implies a memory load. The stack based thing gets
thread_info with pure register accesses. Much better.

For "current()" the per-cpu thing may be better, but if you actually
need the thread-info (not the case here, but in other places), the
stack masking is superior when it works (ie when you don't have
multi-stack issues due to irq's etc)

                Linus
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