[PATCH] Remove some PMU events for FUJITSU-MONAKA

Yoshihiro Furudera (Fujitsu) fj5100bi at fujitsu.com
Tue Mar 4 22:40:28 PST 2025


Hi, James

> 
> Hi, James
> Thank you for your comment.
> 
> > On 27/02/2025 5:40 am, Yoshihiro Furudera wrote:
> > > The following events are not counted properly:
> > >
> > > 0x0037 LL_CACHE_MISS_RD
> > > 0x400B L3D_CACHE_LMISS_RD
> >
> > These two are discoverable so will still appear in
> > /sys/bus/event_source/devices/armv8_pmuv3_0/events/ if the hardware
> > says they exist. It might be better to change the json strings of
> > these two to warn that they don't work if that's the case, otherwise
> > Perf will still list them and you'll be worse off.
> 
> I will leave these 2 events and
> add a warning message to the description in the JSON file.
> I will handle other events in the same way as these 2 events.

I'm thinking of adding one of the following warnings
to the description of events where inaccurate counts 
occur on FUJITSU-MONAKA. 
Is this okay?

1.Simple version
"Note: This event does not count accurately."

2.Detailed version
"Note: This event does not count accurately because it counts as a miss regardless of whether the L3 prefetch is a hit or miss."

I think "2.Detailed version" is better.

example:
{
    "EventCode": "0x0396",
    "EventName": "L2D_CACHE_REFILL_L3D_MISS",
    "BriefDescription": "This event counts operations that cause a miss of the L3 cache. Note: This event does not count accurately because it counts as a miss regardless of whether the L3 prefetch is a hit or miss."
}

Best Regards,
Yoshihiro Furudera


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