libpfm_intel_ivbep_unc_pcu(3) — Linux manual page


LIBPFM(3)               Linux Programmer's Manual              LIBPFM(3)

NAME         top

       libpfm_intel_ivbep_unc_pcu - support for Intel Ivy Bridge-EP
       Power Controller Unit (PCU) uncore PMU

SYNOPSIS         top

       #include <perfmon/pfmlib.h>

       PMU name: ivbep_unc_pcu
       PMU desc: Intel Ivy Bridge-EP PCU uncore PMU

DESCRIPTION         top

       The library supports the Intel Ivy Bridge Power Controller Unit
       uncore PMU.  This PMU model only exists on Ivy Bridge model 62.

MODIFIERS         top

       The following modifiers are supported on Intel Ivy Bridge PCU
       uncore PMU:

       e      Enable edge detection, i.e., count only when there is a
              state transition from no occurrence of the event to at
              least one occurrence. This modifier must be combined with
              a threshold modifier (t) with a value greater or equal to
              one.  This is a boolean modifier.

       t      Set the threshold value. When set to a non-zero value, the
              counter counts the number of HA 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 [0:15].

       ff     Enable frequency band filtering. This modifier applies
              only to the UNC_P_FREQ_BANDx_CYCLES events, where x is
              [0-3].  The modifiers expects an integer in the range
              [0-255]. The value is interpreted as a frequency value to
              be multiplied by 100Mhz. Thus if the value is 32, then all
              cycles where the processor is running at 3.2GHz and more
              are counted.

Frequency band filtering         top

       There are 3 events which support frequency band filtering,
       filter (available via the ff modifier) is stored into a PMU
       shared register which hold all 4 possible frequency bands, one
       per event. However, the library generate the encoding for each
       event individually because it processes events one at a time. The
       caller or the underlying kernel interface may have to merge the
       band filter settings to program the filter register properly.

AUTHORS         top

       Stephane Eranian <>

COLOPHON         top

       This page is part of the perfmon2 (a performance monitoring
       library) project.  Information about the project can be found at
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                             February, 2014                    LIBPFM(3)