libpfm_intel_ivb_unc(3) — Linux manual page


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

NAME         top

       libpfm_intel_ivb_unc - support for Intel Ivy Bridge uncore PMU

SYNOPSIS         top

       #include <perfmon/pfmlib.h>

       PMU name: ivb_unc_cbo0, ivb_unc_cbo1, ivb_unc_cbo2, ivb_unc_cbo3
       PMU desc: Intel Ivy Bridge C-box uncore

DESCRIPTION         top

       The library supports the Intel Ivy Bridge client part (model 58)
       uncore PMU.  The support is currently limited to the Coherency Box,
       so called C-Box for up to 4 physical cores.

       Each physical core has an associated C-Box which it uses to
       communicate with the L3 cache. The C-boxes all support the same set
       of events. However, Core 0 C-box (snb_unc_cbo0) supports an
       additional uncore clock ticks event: UNC_CLOCKTICKS.

MODIFIERS         top

       The following modifiers are supported on Intel Ivy Bridge C-Box
       uncore PMU:

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

       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 counter mask
              modifier (m) with a value greater or equal to one.  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].

       Both the UNC_CBO_CACHE_LOOKUP and UNC_CBO_XSNP_RESPONSE requires two
       umasks to be valid.  For UNC_CBO_CACHE_LOOKUP the first umask must be
       one of the MESI state umasks, the second has to be one of the
       filters.  For UNC_CBO_XSNP_RESPONSE the first umask must be one of
       the snoop types, the second has to be one of the filters.

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 
       ⟨⟩.  If you have a bug report for this
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       page was obtained from the project's upstream Git repository
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       2020-09-18.  (At that time, the date of the most recent commit that
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                                 June, 2013                        LIBPFM(3)