NAME

SYNOPSIS

#include <perfmon/pfmlib.h>
#include <perfmon/pfmlib_core.h>

DESCRIPTION

The libpfm library provides full support for the Intel Core processor family, including the Core 2 Duo series. The interface is defined in pfmlib_core.h. It consists of a set of functions and structures which describe and allow access to the Intel Core processors specific PMU features.

When Intel Core processor specific features are needed to support a measurement, their descriptions must be passed as model-specific input arguments to the pfm_dispatch_events call. The Intel Core
 processors specific input arguments are described in the pfmlib_core_input_param_t structure and the output parameters in pfmlib_core_output_param_t. They are defined as follows:

typedef struct {
        unsigned int    cnt_mask;
        unsigned int    flags;
} pfmlib_core_counter_t;

typedef struct {
        unsigned int pebs_used;
} pfmlib_core_pebs_t;

typedef struct {
        pfmlib_core_counter_t   pfp_core_counters[PMU_CORE_NUM_COUNTERS];
        pfmlib_core_pebs_t      pfp_core_pebs;
        uint64_t                reserved[4];
} pfmlib_core_input_param_t;

typedef struct {
        uint64_t        reserved[8];
} pfmlib_core_output_param_t;

The Intel Core processor provides a few additional per-event features for counters: thresholding, inversion, edge detection. They can be set using the pfp_core_counters data structure for each event. The flags field can be initialized as follows:

• PFMLIB_CORE_SEL_INV: Inverse the results of the cnt_mask comparison when set
• PFMLIB_CORE_SEL_EDGE: Enables edge detection of events.

The cnt_mask field contains is used to set the event threshold. The value of the counter is incremented each time the number of occurrences per cycle of the event is greater or equal to the value of the field. When zero all occurrences are counted.

Support for Precise-Event Based Sampling (PEBS)

Support for Intel Core 2 Duo processors

ERRORS

SEE ALSO

AUTHOR