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Subject: Re: [tip:perfcounters/core] perf_counter: x86: Fix call-chain
 support to use NMI-safe methods
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
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Date: Mon, 15 Jun 2009 20:51:57 +0200
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On Mon, 2009-06-15 at 14:48 -0400, Mathieu Desnoyers wrote:
> we should not care that much about the performance hit of
> saving/restoring the cr2 register at each nmi entry/exit.

But we do, perf counters very much cares about nmi performance.