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SubjectRe: [tip:perfcounters/core] perf_counter: x86: Fix call-chain support to use NMI-safe methods
* Peter Zijlstra ( wrote:
> 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.

To a point where it cannot afford a simple register save/restore ?

There is "caring" and "_caring_". I am tempted to ask what NMI handler
execution frequency you have in mind here to figure out if we are not
trying to optimize sub-nanoseconds per minutes. ;)


Mathieu Desnoyers
OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F BA06 3F25 A8FE 3BAE 9A68

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