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Re: [Xen-devel] [PATCH] linux: don't bring up CPUs that can never be use

To: Jan Beulich <jbeulich@xxxxxxxxxx>, <xen-devel@xxxxxxxxxxxxxxxxxxx>
Subject: Re: [Xen-devel] [PATCH] linux: don't bring up CPUs that can never be used
From: Keir Fraser <Keir.Fraser@xxxxxxxxxxxx>
Date: Mon, 14 Aug 2006 14:56:18 +0100
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On 14/8/06 2:23 pm, "Jan Beulich" <jbeulich@xxxxxxxxxx> wrote:

>> I'm a little bit wary of the second hunk. Although it's probably okay,
> is it
>> actually required? Looks like the first hunk is what fixes the issue.
> It's probably not strictly required, but sill better than iterating
> over NR_CPUS, as
> that is what mainline is in the process of phasing out. The only
> difference I can
> see to the results of the original code is that for cpu 0 the two array
> members
> now also get (re-)initialized here - but the value stored should be the
> same as
> may have been stored earlier.

If it's true that those maps only get interrogated for CPUs in the
cpu_online_map, could we remove that loop altogether? We initialise the map
entries for CPUs as they're brought online in __cpu_up(): should that

 -- Keir

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