libpfm_intel_skx_unc_upi(3) — Linux manual page


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

NAME         top

       libpfm_intel_skx_unc_upi - support for Intel Skylake X Server UPI
       uncore PMU

SYNOPSIS         top

       #include <perfmon/pfmlib.h>

       PMU name: skx_unc_upi[0-2]
       PMU desc: Intel Skylake X Server UPI uncore PMU

DESCRIPTION         top

       The library supports the Intel Skylake X Server UPI uncore PMU.

MODIFIERS         top

       The following modifiers are supported on Intel Skylake X server
       UPI 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 QPI 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].

       i      Invert the meaning of the threshold or edge filter. If
              set, the event counts when strictly less than N
              occurrences occur per cycle if threshold is set to N. When
              invert is set, then threshold must be set to non-zero
              value. If set, the event counts when the event transitions
              from occurring to not occurring (falling edge) when edge
              detection is set. This is a boolean modifier

BASIC_HDR_MATCH events         top

       The library also supports the special RXL_BASIC_HDR_MATCH and
       TXL_BASIC_HDR_MATCH opcode matcher events. These events have a
       lot more filters available in the form of either a modifier
       (listed below) or specific umasks.  The following modifiers are
       available in additional to the standard listed above:

       rcsnid Specify a RCS Node identifier as an integer in the range
              [0-15]. Default: 0

       dnid   Specify a destination Node identifier as an integer in the
              range [0-15]. Default: 0

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 manual page, send it to  This page was obtained
       from the project's upstream Git repository
       ⟨git:// perfmon2-libpfm4⟩ on
       2023-06-23.  (At that time, the date of the most recent commit
       that was found in the repository was 2023-06-07.)  If you
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                              January, 2018                    LIBPFM(3)