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Subject: Re: [RFC][PATCH 00/11] perf pmu interface -v2
From: Peter Zijlstra <peterz@infradead.org>
To: Corey Ashford <cjashfor@linux.vnet.ibm.com>
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Date: Wed, 30 Jun 2010 20:11:28 +0200
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On Wed, 2010-06-30 at 10:19 -0700, Corey Ashford wrote:
> However, there still are concerns relative to writing these control 
> registers from an interrupt handler because of the latency that will be 
> incurred, however slow we choose to do the event rotation.  So at least 
> for the Wire-Speed processor, we may need a worker thread of some sort 
> to hand off the work to. 

Right, once we have per-pmu contexts we can look at having means to
over-ride the means of rotation, such that the pmu can optionally drive
it itself instead of through the common tick.