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PMCx060 unit mask 0x10 replaces >>> PMCx081 for counting IC misses but there is no suitable replacement for >>> counting IC accesses. >> >> can you link to the errata document that describes this problem as well as >> maybe give a rundown of how and why this breaks? > > I've delayed this patch until these details are cleared up. > Both of these events were removed from the Processor Programming Reference starting with Zen 2. Errata is missing for Zen 1 but it is known that these events are broken. A quick test like the following will show that PMCx081 undercounts IC misses compared to PMCx060 with unit mask 0x10. $ perf stat -e "{cpu/event=0x81/,cpu/event=0x60,umask=0x10/}" ./ic-miss Performance counter stats for './ic-miss': 2,105 cpu/event=0x81/u 30,826 cpu/event=0x60,umask=0x10/u 1.650143599 seconds time elapsed 1.646070000 seconds user 0.000998000 seconds sys If its acceptable, I can send out a v2 with the details above.