Re: [PATCH v1 09/10] perf/x86/uncore: add hrtimer to SNB uncore IMC PMU

2014-02-09 Thread Yan, Zheng
On 02/03/2014 08:55 PM, Stephane Eranian wrote: > This patch is needed because that PMU uses 32-bit free > running counters with no interrupt capabilities. > > On SNB/IVB/HSW, we used 20GB/s theoretical peak to calculate > the hrtimer timeout necessary to avoid missing an overflow. > That delay is

[PATCH v1 09/10] perf/x86/uncore: add hrtimer to SNB uncore IMC PMU

2014-02-03 Thread Stephane Eranian
This patch is needed because that PMU uses 32-bit free running counters with no interrupt capabilities. On SNB/IVB/HSW, we used 20GB/s theoretical peak to calculate the hrtimer timeout necessary to avoid missing an overflow. That delay is set to 5s to be on the cautious side. The SNB IMC uses fre