NAME

       pfm_get_event_next - iterate over events

SYNOPSIS

       #include <perfmon/pfmlib.h>

       int pfm_get_event_next(int idx);

DESCRIPTION

       Events  are  uniquely  identified with opaque integer identifiers.  There is no guaranteed
       order within identifiers. Thus, to list all the events, it is necessary to use iterators.

       Events are grouped in tables within the library. A table  usually  corresponds  to  a  PMU
       model  or  family.  The  library  contains  support  for  multiple PMU models, thus it has
       multiple tables. Based  on  the  host  hardware  and  software  environments,  tables  get
       activated  when  the  library  is  initialized via pfm_initialize(). Events from activated
       tables are called active events. Events from non-activated  tables  are  called  supported
       events.

       Event identifiers are usually retrieved via pfm_find_event() or when encoding events.

       To  iterate  over a list of events for a given PMU model, all that is needed is an initial
       identifier  for  the  PMU.  The  first  event   identifier   is   usually   obtained   via
       pfm_get_pmu_info().

       The pfm_get_event_next() function returns the identifier of next supported event after the
       one passed in idx. This iterator stops when the last  event  for  the  PMU  is  passed  as
       argument, in which case the function returns -1.

       void list_pmu_events(pfm_pmu_t pmu)
       {
          struct pfm_event_info info;
          struct pfm_pmu_info pinfo;
          int i, ret;

          memset(&info, 0, sizeof(info));
          memset(&pinfo, 0, sizeof(pinfo));

          info.size = sizeof(info);
          pinfo.size = sizeof(pinfo);

          ret = pfm_get_pmu_info(pmu, &pinfo);
          if (ret != PFM_SUCCESS)
             errx(1, "cannot get pmu info");

          for (i = pinfo.first_event; i != -1; i = pfm_get_event_next(i)) {
             ret = pfm_get_event_info(i, &info);
             if (ret != PFM_SUCCESS)
               errx(1, "cannot get event info");

               printf("%s Event: %s::%s\n",
                      pinfo.present ? "Active" : "Supported",
                      pinfo.name, info.name);
         }
       }

RETURN

       The  function  returns  the identifier of the next supported event. It returns -1 when the
       argument is already the last event for the PMU.

ERRORS

       No error code, besides -1, is returned by this function.

SEE ALSO

       pfm_find_event(3)

AUTHOR

       Stephane Eranian <eranian@gmail.com>

                                         September, 2009                                LIBPFM(3)