LIBPFM(3) Linux Programmer's Manual LIBPFM(3)NAME
libpfm_i386_p6 - support for Intel P6 processor family
SYNOPSIS
#include <perfmon/pfmlib.h>
#include <perfmon/pfmlib_i386_p6.h>
DESCRIPTION
The libpfm library provides full support for the P6 processor family,
including the Pentium M processor. The interface is defined in pfm‐
lib_i386_p6.h. It consists of a set of functions and structures which
describe and allow access to the P6 processors specific PMU features.
When P6 processor specific features are needed to support a measure‐
ment, their descriptions must be passed as model-specific input argu‐
ments to the pfm_dispatch_events() function. The P6 processors specific
input arguments are described in the pfmlib_i386_p6_input_param_t
structure and the output parameters in pfmlib_i386_p6_output_param_t.
They are defined as follows:
typedef struct {
unsigned int cnt_mask;
unsigned int flags;
} pfmlib_i386_p6_counter_t;
typedef struct {
pfmlib_i386_p6_counter_t pfp_i386_p6_counters[PMU_I386_P6_NUM_COUNTERS];
uint64_t reserved[4];
} pfmlib_i386_p6_input_param_t;
typedef struct {
uint64_t reserved[8];
} pfmlib_i386_p6_output_param_t;
The P6 processor provides a few additional per-event features for coun‐
ters: thresholding, inversion, edge detection. They can be set using
the pfp_i386_p6_counters data structure for each event. The flags
field can be initialized as follows:
PFMLIB_I386_P6_SEL_INV
Inverse the results of the cnt_mask comparison when set
PFMLIB_I386_P6_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.
Handling of Pentium M
The library provides full support for the Pentium M PMU. A Pentium
implements more events than a generic P6 processor. The library autode‐
tects the host processor and can distinguish generic P6 processor from
a Pentium. Thus no special call is needed.
ERRORS
Refer to the description of the pfm_dispatch_events() function for
errors.
SEE ALSOpfm_dispatch_events(3) and set of examples shipped with the library
AUTHOR
Stephane Eranian <eranian@hpl.hp.com>
September, 2005 LIBPFM(3)
