Blob Blame History Raw
.TH LIBPFM 3  "September, 2009" "" "Linux Programmer's Manual"
.SH NAME
libpfm_intel_wsm - support for Intel Westmere core PMU
.SH SYNOPSIS
.nf
.B #include <perfmon/pfmlib.h>
.sp
.B PMU name: wsm
.B PMU desc: Intel Westmere
.B PMU name: wsm_dp
.B PMU desc: Intel Westmere DP
.sp
.SH DESCRIPTION
The library supports the Intel Westmere 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 (models 37, 44).

.SH MODIFIERS
The following modifiers are supported on Intel Westmere processors:
.TP
.B u
Measure at user level which includes privilege levels 1, 2, 3. This corresponds to \fBPFM_PLM3\fR.
This is a boolean modifier.
.TP
.B k
Measure at kernel level which includes privilege level 0. This corresponds to \fBPFM_PLM0\fR.
This is a boolean modifier.
.TP
.B i
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
.TP
.B 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.
.TP
.B 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].
.TP
.B t
Measure on both threads at the same time assuming hyper-threading is enabled. This is a boolean modifier.
.TP
.B ldlat
Pass a latency threshold to the MEM_INST_RETIRED:LATENCY_ABOVE_THRESHOLD event.
This is an integer attribute that must be in the range [3:65535]. It is required
for this event.  Note that the event must be used with precise sampling (PEBS).

.SH OFFCORE_RESPONSE events
The library is able to encode the OFFCORE_RESPONSE_0 and OFFCORE_RESPONSE_1 events.
Those are special events because they, each, need a second MSR (0x1a6 and 0x1a7 respectively)
to be programmed for the event to count properly. Thus two values are necessary for each event.
The first value can be programmed on any of the generic counters. The second value goes into
the dedicated MSR (0x1a6 or 0x1a7).

The OFFCORE_RESPONSE events are exposed as normal events with several umasks which are divided in
two groups: request and response. The user must provide \fBat least\fR one umask from each group.
For instance, OFFCORE_RESPONSE_0:ANY_DATA:LOCAL_DRAM.

When using \fBpfm_get_event_encoding()\fR, two 64-bit values are returned. The first value
corresponds to what needs to be programmed into any of the generic counters. The second value
must be programmed into the corresponding dedicated MSR (0x1a6 or 0x1a7).

When using an OS-specific encoding routine, the way the event is encoded is OS specific. Refer to
the corresponding man page for more information.

.SH AUTHORS
.nf
Stephane Eranian <eranian@gmail.com>
.if
.PP