.TH LIBPFM 4 "September, 2009" "" "Linux Programmer's Manual"
libpfm_intel_nhm - support for Intel Nehalem core PMU
.B #include <perfmon/pfmlib.h>
.B PMU name: nhm
.B PMU desc: Intel Nehalem
The library supports the Intel Nehalem core PMU. It should be noted that
this PMU model only covers the each core's PMU and not the socket level
PMU. It is provided separately. Support is provided for the Intel Core i7
and Core i5 processors.
The following modifiers are supported on Intel Nehalem processors:
Measure at user level which includes privilege levels 1, 2, 3. This is a boolean modifier.
Measure at kernel level which includes privilege level 0. This is a boolean modifier.
Invert the meaning of the event. The counter will now count cycles in which the event is \fBnot\fR
occurring. This is a boolean modifier
Enable edge detection, i.e., count only when there is a state transition. This is a boolean modifier.
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].
Measure on both threads at the same time assuming hyper-threading is enabled. This is a boolean modifier.
.SH ENVIRONMENT VARIABLES
It is possible to force activation of the Intel Nehalem support using the \fBLIBPFM_FORCE_PMU\fR variable.
The PMU name, nhm, must be passed. No additional options are supported.
Stephane Eranian <firstname.lastname@example.org>