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Date: Sat, 13 Oct 2007 09:37:15 +0530
Message-ID: <86k5prac98.wl%koshy@unixconsulting.co.in>
To: Alfred Perlstein <alfred@freebsd.org>
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From: Joseph Koshy <jkoshy@FreeBSD.org>
Sender: Joseph Koshy <jkoshy.freebsd@gmail.com>
Cc: jkoshy@freebsd.org, smp@freebsd.org
Subject: Re: hwpmc dealing with sparse cpu systems.
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> One of the engineers here seems to have found a bug in the
> hwpmc_mod.c module.  The problem we have is that cpuids can be
> greater than mp_ncpus due to sparseness.

> Does the fix here make sense?  (replace mp_ncpus with MAXCPU)

No, a simple global substitution would probably be incorrect because
it would allow userland to get hwpmc to attempt operations on
non-existent CPUs.

I will look into this.

Regards,
Koshy
<jkoshy@freebsd.org>