Perf record

Hi,

I'd like to use perf record to look into some performance counters. I'm using a ThunderX2 system with Centos 8. When i use any of the uncore counters such as uncore_l3c_0/evict_request/, uncore_dmc_1/cnt_cycles/, uncore_dmc_0/cnt_cycles/ I get the same error "The sys_perf_event_open() syscall returned with 22 (Invalid argument) for event ..." Do you guys have any suggestions? see below for more details. Thanks

# rpm -qa |grep perf
python3-perf-4.18.0-240.el8.aarch64
perftest-4.4-3.el8.aarch64
perf-4.18.0-240.el8.aarch64
qperf-0.4.11-1.el8.aarch64
# uname -r
4.18.0-240.el8.aarch64
# perf record -a -e uncore_dmc_0/cnt_cycles/ ls
Lowering default frequency rate to 1600.
Please consider tweaking /proc/sys/kernel/perf_event_max_sample_rate.
Error:
The sys_perf_event_open() syscall returned with 22 (Invalid argument) for event (uncore_dmc_0/cnt_cycles/).
/bin/dmesg | grep -i perf may provide additional information.
# /bin/dmesg | grep -i perf  |tail -n 3
[194444.313119] perf: interrupt took too long (38453 > 38357), lowering kernel.perf_event_max_sample_rate to 5200
[194444.388648] perf: interrupt took too long (48338 > 48066), lowering kernel.perf_event_max_sample_rate to 4100
[194961.878397] perf: interrupt took too long (60611 > 60422), lowering kernel.perf_event_max_sample_rate to 3200

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