NAME

       libpfm_intel_tmt - support for Intel Tremont core PMU

SYNOPSIS

       #include <perfmon/pfmlib.h>

       PMU name: tmt
       PMU desc: Intel Tremont

DESCRIPTION

       The library supports the Intel Tremont core PMU.

MODIFIERS

       The following modifiers are supported on Intel Tremont processors:

       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  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].

OFFCORE_RESPONSE events

       Intel   Tremont   provides   two   offcore_response   events:    OFFCORE_RESPONSE_0    and
       OFFCORE_RESPONSE_1. The  OCR event is aliased to OFFCORE_RESPONSE_0.

       Those  events  need special treatment in the performance monitoring infrastructure because
       each event uses an  extra  register  to  store  some  settings.  Thus,  in  case  multiple
       offcore_response  events  are  monitored  simultaneously,  the  kernel needs to manage the
       sharing of that extra register.

       The offcore_response event is exposed as a normal event by the library. The extra settings
       are exposed as regular umasks. The library takes care of encoding the events according for
       the underlying kernel interface.

       On Intel Tremont, it is not possible to  combine  the  request,  supplier,  snoop,  fields
       anymore to avoid invalid combinations. As such, the umasks provided by the library are the
       only ones supported and validated.

AUTHORS

       Stephane Eranian <eranian@gmail.com>

                                           March, 2020                                  LIBPFM(3)