Re: [PATCH] perf metricgroup: Fix system PMU metrics

[John Garry]

On 19/01/2021 10:56, Joakim Zhang wrote:
> It seems have other issue compared to 5.10 kernel after switching to this framework, below metric can't work.
> "MetricExpr": "(( imx8_ddr0@read\\-cycles@ + imx8_ddr0@write\\-cycles@ ) * 4 * 4 / duration_time) / (750 * 1000000 * 4 * 4)"
> After change to:
> "MetricExpr": "(( imx8mm_ddr.read_cycles + imx8mm_ddr.write_cycles ) * 4 * 4 / duration_time) / (750 * 1000000 * 4 * 4)",

It seems that any metric which includes "duration_time" is broken, even 
on x86:

john@localhost:~/acme/tools/perf> sudo ./perf stat -v -M 
L1D_Cache_Fill_BW sleep 1
Using CPUID GenuineIntel-6-3D-4
metric expr 64 * l1d.replacement / 1000000000 / duration_time for 
L1D_Cache_Fill_BW
found event duration_time
found event l1d.replacement
adding {l1d.replacement}:W,duration_time
l1d.replacement -> cpu/umask=0x1,(null)=0x1e8483,event=0x51/
Segmentation fault


Seems to be from my commit c2337d67199 ("perf metricgroup: Fix metrics 
using aliases covering multiple PMUs")

I'll look to fix it now.

Thanks,
John