Monitoring perf::CPU-CYCLES native event problem

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Monitoring perf::CPU-CYCLES native event problem

Postby Perveance » Thu May 09, 2013 9:51 pm

Hi all,

I am using papi-5.1.0 on Intel Q9400 ubuntu desktop.

I am trying to monitor native event (shown by ./util/papi_native_avail) perf::CPU-CYCLES of perf_event component, which I add to eventset by using PAPI_event_name_to_code function:

Code: Select all
retval = PAPI_event_name_to_code("perf::CPU-CYCLES", &event_code);

For this event, the returned event code is 0x40000025

To enumerate and list all available components and events, I use following code:

Code: Select all
  numcmp = PAPI_num_components();

  printf("numcmp = %d\n", numcmp);

  for (cmp_idx = 0; cmp_idx < numcmp ; cmp_idx++) {
    cmp_info = PAPI_get_component_info(cmp_idx);
    if (cmp_info == NULL) {

    code = PAPI_NATIVE_MASK;
    r = PAPI_enum_cmp_event(&code, PAPI_ENUM_FIRST, cmp_idx);
      while (r == PAPI_OK) {
        retval = PAPI_event_code_to_name(code, event_name);
        if (retval != PAPI_OK) {
          printf("PAPI_event_code_to_name return error(%d) in %s\n", retval, __func__);

        printf("0x%x %s\n", code, event_name);

        r = PAPI_enum_cmp_event(&code, PAPI_ENUM_EVENTS, cmp_idx);

The output of this code snippet for perf::CPU-CYCLES is

0x400000a3 perf::CPU-CYCLES

As you can see the code is different from code returned by PAPI_event_code_to_name() function (0x40000025).

Could anyone please clarify where is my mistake and misunderstanding? I need to monitor perf::* native events.

Another question is, what is the difference between following 3 events perf::PERF_COUNT_HW_CPU_CYCLES, perf::CYCLES and perf::CPU-CYCLES?

Thank you in advance!

Posts: 2
Joined: Thu May 09, 2013 9:11 pm

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