Re: [PATCH v2 2/3] perf vendor events amd: add Zen2 events

From: Kim Phillips
Date: Fri Feb 28 2020 - 11:24:36 EST


On 2/28/20 10:00 AM, Vijay Thakkar wrote:
>>> + {
>>> + "EventName": "ls_pref_instr_disp.prefetch_nta",
>>> + "EventCode": "0x4b",
>>> + "BriefDescription": "Software Prefetch Instructions (PREFETCHNTA instruction) Dispatched.",
>>> + "PublicDescription": "Software Prefetch Instructions (PREFETCHNTA instruction) Dispatched.",
>>> + "UMask": "0x4"
>>> + },
>>> + {
>>> + "EventName": "ls_pref_instr_disp.store_prefetch_w",
>>> + "EventCode": "0x4b",
>>> + "BriefDescription": "Software Prefetch Instructions (3DNow PREFETCHW instruction) Dispatched.",
>>> + "PublicDescription": "Software Prefetch Instructions (3DNow PREFETCHW instruction) Dispatched.",
>>> + "UMask": "0x2"
>>> + },
>>> + {
>>> + "EventName": "ls_pref_instr_disp.load_prefetch_w",
>>> + "EventCode": "0x4b",
>>> + "BriefDescription": "Prefetch, Prefetch_T0_T1_T2.",
>>> + "PublicDescription": "Software Prefetch Instructions Dispatched. Prefetch, Prefetch_T0_T1_T2.",
>>> + "UMask": "0x1"
>>> + },
> These three are present in the PPR for model 71h (56176 Rev 3.06 - Jul
> 17, 2019) but are missing from the PPR for model 31h (55803 Rev 0.54 -
> Sep 12, 2019). Not sure what to do about it.

They're producing nonzero counts on my model 31h, so leave them in?

> Similarly, PMC 0x0AF - Dispatch Resource Stall Cycles 0 only has one
> subcounter in the model 31h PPR, whereas the PPR for 71h is the one that
> contains the eight subcounters we see in the mainline right now.

I'm getting nonzero values on my model 31h for that event's
various unit masks, too.

> There could be more subtle differences like these, since I have not
> really compared the PPR versions that thoroughly. I was going with the
> assumption that since both are for SoCs based on the Zen2, they would
> have identical events.

I think that's a reasonable assumption.

> Otherwise, I have made all the other changes and corrections, and will
> send in v3 after you suggest how to proceed about the above two.

Thanks, I'd veer toward making them available despite differences in PPR
versions.

Thanks,

Kim