[PATCH 00/11] arm: perf: add support for heterogeneous PMUs

Will Deacon will.deacon at arm.com
Mon Nov 17 03:24:47 PST 2014


On Fri, Nov 07, 2014 at 04:25:25PM +0000, Mark Rutland wrote:
> In systems with heterogeneous CPUs (e.g. big.LITTLE) the associated PMUs
> also differ in terms of the supported set of events, the precise
> behaviour of each of those events, and the number of event counters.
> Thus it is not possible to expose these PMUs as a single logical PMU.
> 
> Instead a logical PMU is created per CPU microarchitecture, which events
> can target directly:
> 
> $ perf stat \
>   -e armv7_cortex_a7/config=0x11/ \
>   -e armv7_cortex_a15/config=0x11/ \
>   ./test
> 
>  Performance counter stats for './test':
> 
>            7980455      armv7_cortex_a7/config=0x11/                                    [27.29%]
>            9947934      armv7_cortex_a15/config=0x11/                                    [72.66%]
> 
>        0.016734833 seconds time elapsed
> 
> This series is based atop of my recent preparatory rework [1,2].

Modulo the patches I commented on, the ARM perf bits look fine to me. For
those:

  Acked-by: Will Deacon <will.deacon at arm.com>

However, you need to get the event_filter_match change into the core code
before I can queue anything.

Will



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