Re: [PATCH 01/22] x86: add methods for writing of an MSR on severalCPUs

From: Borislav Petkov
Date: Mon May 25 2009 - 07:02:16 EST

On Fri, May 22, 2009 at 09:47:49AM -0700, H. Peter Anvin wrote:
> Borislav Petkov wrote:
> >>>
> >> If nothing else it might matter for boot time. Serializing *anything*
> >> across a large number of CPUs can be very expensive.
> >
> > well, upon a closer look, smp_call_function_many() skips over the CPU
> > it is executing on and there's currently work in that area to extend
> > that API:
> >
> > However, according to Linus' comments, it looks like this would need a
> > bit of work so I guess we should wait with the concurrency stuff a bit,
> > no?
> >
> Well, we can introduce the API now if that's where we intend it to go.

Ok, here it is (patches as a reply to that mail). I've added a temporary
workaround for smp_call_function_many() not running on the CPU we're on.


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