CODEWITHSUNDEEP
profilingperftscmsr
assembly_question
assembly_question

Reputation: 39

Perf Error: The sys_perf_event_open() syscall returned with 22 (Invalid argument) for event (msr/tsc/)

I am using perf to monitor the system for certain events. However, I get the following error and I have no idea where it comes from,as the event is listed in perf list

sudo perf record -e msr/tsc/ -a

Error:
The sys_perf_event_open() syscall returned with 22 (Invalid argument) for event (msr/tsc/).
/bin/dmesg may provide additional information.
No CONFIG_PERF_EVENTS=y kernel support configured?

How can I check No CONFIG_PERF_EVENTS=y kernel support configured?

**Some test results: 

sudo dmesg | grep "perf\|pmu"**
[    0.029179] ENERGY_PERF_BIAS: Set to 'normal', was 'performance'
[    0.029179] ENERGY_PERF_BIAS: View and update with x86_energy_perf_policy(8)
[ 9475.406967] perf: interrupt took too long (2509 > 2500), lowering kernel.perf_event_max_sample_rate to 79500
[ 9475.990901] perf: interrupt took too long (3146 > 3136), lowering kernel.perf_event_max_sample_rate to 63500
[ 9476.886941] perf: interrupt took too long (3942 > 3932), lowering kernel.perf_event_max_sample_rate to 50500
[76057.268195] perf: interrupt took too long (4934 > 4927), lowering kernel.perf_event_max_sample_rate to 40500
[167368.007839] perf: interrupt took too long (6171 > 6167), lowering kernel.perf_event_max_sample_rate to 32250
[168338.165608] perf: interrupt took too long (7804 > 7713), lowering kernel.perf_event_max_sample_rate to 25500

perf list |grep msr

  msr/aperf/                                         [Kernel PMU event]
  msr/mperf/                                         [Kernel PMU event]
  msr/pperf/                                         [Kernel PMU event]
  msr/smi/                                           [Kernel PMU event]
  msr/tsc/

sudo uname -a Linux bla 4.9.0-amd64 #1 SMP Debian 4.9.130-2 (2018-10-27) x86_64 GNU/Linux

sudo /proc/config.gz returns command not found Any help/ideas are appreciated.

Upvotes: 3

Views: 6039

Answers (2)

Zulan
Zulan

Reputation: 22670

It is possible to collect this information with perf record by using group sampling. For example, the following command

perf record -a -e '{cycles,msr/aperf/,msr/tsc/}:S'

collects values of all three events based on the cycle (first counter) overflow. The undocumented :S modifier is necessary, it makes sure that only the leader of the group triggers samples. For seeing this information, you use perf report --group, the parameter may not be necessary. I'm afraid the actual values for each sample are only visible in the very verbose perf script -D.

Upvotes: 4

Arnabjyoti Kalita
Arnabjyoti Kalita

Reputation: 2431

There was a patch introduced in perf to support MSR Performance Monitoring Units. These MSR PMUs support free-running MSR counters. These counters include time and frequency-based counters like TSC, IA32_APERF, IA32_MPERF and IA32_PPERF.

These MSR events do not support sampling modes. As visible by this line of code in the linux kernel(v4.9) source code.

Snippet:

if event->attr.sample_period) /* no sampling */ return -EINVAL;

perf_events can instrument in three ways (counting events, sampling events and bpf events). Remember that when you run perf record, you are now invoking the sampling mode. Even though you do not explicitly specify the sampling period, internally sampling is happening at a default sampling frequency.

To count msr events, you need to run perf_events in counting/aggregation mode. You run perf stat for this --

perf stat -e msr/tsc/ -a

^C

Performance counter stats for 'system wide':

 34,83,07,96,035      msr/tsc/                                                    

 2.419151644 seconds time elapsed

Read this to understand more about counting and sampling events/modes.

Upvotes: 3

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