[PATCH v2 00/22] KVM: ARM64: Add guest PMU support

[Christoffer Dall]

Hi Shannon,

On Fri, Sep 11, 2015 at 04:54:53PM +0800, Shannon Zhao wrote:
> From: Shannon Zhao <shannon.zhao at linaro.org>
> 
> This patchset adds guest PMU support for KVM on ARM64. It takes
> trap-and-emulate approach. When guest wants to monitor one event, it
> will be trapped by KVM and KVM will call perf_event API to create a perf
> event and call relevant perf_event APIs to get the count value of event.
> 
> Use perf to test this patchset in guest. When using "perf list", it
> shows the list of the hardware events and hardware cache events perf
> supports. Then use "perf stat -e EVENT" to monitor some event. For
> example, use "perf stat -e cycles" to count cpu cycles and
> "perf stat -e cache-misses" to count cache misses.
> 
> Below are the outputs of "perf stat -r 5 sleep 5" when running in host
> and guest.
> 
> Host:
>  Performance counter stats for 'sleep 5' (5 runs):
> 
>           0.551428      task-clock (msec)         #    0.000 CPUs utilized            ( +-  0.91% )
>                  1      context-switches          #    0.002 M/sec
>                  0      cpu-migrations            #    0.000 K/sec
>                 48      page-faults               #    0.088 M/sec                    ( +-  1.05% )
>            1150265      cycles                    #    2.086 GHz                      ( +-  0.92% )
>    <not supported>      stalled-cycles-frontend
>    <not supported>      stalled-cycles-backend
>             526398      instructions              #    0.46  insns per cycle          ( +-  0.89% )
>    <not supported>      branches
>               9485      branch-misses             #   17.201 M/sec                    ( +-  2.35% )
> 
>        5.000831616 seconds time elapsed                                          ( +-  0.00% )
> 
> Guest:
>  Performance counter stats for 'sleep 5' (5 runs):
> 
>           0.730868      task-clock (msec)         #    0.000 CPUs utilized            ( +-  1.13% )
>                  1      context-switches          #    0.001 M/sec
>                  0      cpu-migrations            #    0.000 K/sec
>                 48      page-faults               #    0.065 M/sec                    ( +-  0.42% )
>            1642982      cycles                    #    2.248 GHz                      ( +-  1.04% )
>    <not supported>      stalled-cycles-frontend
>    <not supported>      stalled-cycles-backend
>             637964      instructions              #    0.39  insns per cycle          ( +-  0.65% )
>    <not supported>      branches
>              10377      branch-misses             #   14.198 M/sec                    ( +-  1.09% )
> 
>        5.001289068 seconds time elapsed                                          ( +-  0.00% )
> 
> This patchset can be fetched from [1] and the relevant QEMU version for
> test can be fetched from [2].
> 
Is there a changelog for this patch set somewhere?

If not, can you include this in v3 addressing Marc's comments?

Thanks,
-Christoffer