libpfm_intel_skx_unc_pcu - support for Intel Skylake X Power Controller Unit (PCU) uncore PMU
Contents
Description
The library supports the Intel Skylake X Server Power Controller Unit uncore PMU.
Frequency Band Filtering
There are 3 events which support frequency band filtering, namely, UNC_P_FREQ_BAND0_CYCLES,
UNC_P_FREQ_BAND1_CYCLES, UNC_P_FREQ_BAND2_CYCLES, UNC_P_FREQ_BAND3_CYCLES. The frequency 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.
Modifiers
The following modifiers are supported on Intel Skylake X server 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].
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
Name
libpfm_intel_skx_unc_pcu - support for Intel Skylake X Power Controller Unit (PCU) uncore PMU
Synopsis
#include<perfmon/pfmlib.h>PMUname:skx_unc_pcuPMUdesc:IntelSkylakeXServerPCUuncorePMU
