libpfm_intel_x86_arch — support for Intel X86 architectural PMU

Synopsis

#include <perfmon/pfmlib.h>

PMU name: ix86arch
PMU desc: Intel X86 architectural PMU

Description

The library supports any processor implementing the Intel architectural PMU. This is a minimal PMU with a variable number of counters but predefined set of events. It is implemented in all recent processors  starting with Intel Core Duo/Core Solo.

It acts as a default PMU support in case the library is run on a very recent processor for which the specific support has not yet been implemented.

Modifiers

The following modifiers are supported on Intel architectural PMU:

u

Measure at user level which includes privilege levels 1, 2, 3. This corresponds to PFM_PLM3. This is a boolean modifier.

k

Measure at kernel level which includes privilege level 0. This corresponds to PFM_PLM0. This is a boolean modifier.

i

Invert the meaning of the event. The counter will now count cycles in which the event is not occurring. This is a boolean modifier

e

Enable edge detection, i.e., count only when there is a state transition. This is a boolean modifier.

c

Set the counter mask value. The mask acts as a threshold. The counter will count the number of cycles in which the number of occurrences of the event is greater or equal to the threshold. This is an integer modifier with values in the range [0:255].

t

Measure on both threads at the same time assuming hyper-threading is enabled. This modifier requires at least version 3 of the architectural PMU. This is a boolean modifier.

Authors

Stephane Eranian <eranian@gmail.com>

Info

September, 2009 Linux Programmer's Manual