NAME
pfm_find_event, pfm_find_full_event, pfm_find_event_bycode,
pfm_find_event_bycode_next, pfm_find_event_mask - search for events and
unit masks
SYNOPSIS
#include <perfmon/pfmlib.h>
int pfm_find_event(const char *str, unsigned int *desc);
int pfm_find_full_event(const char *str, pfmlib_event_t *e);
int pfm_find_event_bycode(int code, unsigned int *desc);
int pfm_find_event_bycode_next(unsigned int desc1, int code, unsigned int *desc);
int pfm_find_event_mask(unsigned int *idx, const char *str, unsigned int *mask_idx);
DESCRIPTION
The PMU counters can be programmed to count the number of occurrences
of certain events. The number of events varies from one PMU model to
the other. Each event has a name and a code which is used to program
the actual PMU register. Some event may need to be further qualified
with unit masks.
The library does not directly expose the event code, nor unit mask
code, to user applications because it is not necessary. Instead
applications use names to query the library for particular information
about events. Given an event name, the library returns an opaque
descriptor. Each descriptor is unique and has no relationship to the
event code.
The set of functions described here can be used to get an event
descriptor given either the name of the event or its code. Several
events may share the same code. An event name is a string structured
as: event_name[:unit_mask1[:unit_mask2]].
The pfm_find_event function is a general purpose search routine. Given
an event name in str, it returns the descriptor for the corresponding
event. If unit masks are provided, they are not taken into account.
This function is being deprecated in favor of pfm_find_full_event_name.
The pfm_find_full_event function is a general purpose search routine.
Given an event name, it returns in ev, the full event descriptor that
includes the event descriptor in ev->event and the unit mask
descriptors in ev->unit_masks. The number of unit masks descriptors
returned is indicated in ev->num_masks. This function is the preferred
search function.
The pfm_find_event_bycode searches for an event given its code
represented as an integer. It returns in desc, the event code. Unit
masks are ignored.
Because there can be several events with the same code, the library
provides the pfm_find_event_bycode_next to search for other events with
the same code. Given an event desc1 and a code, this function will look
for the next event with the same code. If such an event exists, its
descriptor will be stored into desc. It is not necessary to have
called pfm_find_event_bycode prior to calling this function. This
function is fully threadsafe as it does not maintain any state between
calls.
The pfm_find_event_mask function is used to find the unit mask
descriptor based on its name passed in str for the event specified in
idx. Some events do not have unit masks, in which case this function
returns an error.
RETURN
All functions return whether or not the call was successful. A return
value of PFMLIB_SUCCESS indicates success, otherwise the value is the
error code.
ERRORS
PFMLIB_ERR_NOINIT the library has not been initialized properly.
PFMLIB_ERR_INVAL
the event descriptor is invalid, or the pointer argument is
NULL.
PFMLIB_ERR_NOTFOUND
no matching event or unit mask was found.
AUTHOR
Stephane Eranian <eranian@hpl.hp.com>
August, 2006 LIBPFM(3)