поддержка Intel Broadwell Server C-Box uncore PMU (support for Intel Broadwell Server C-Box uncore PMU)
Имя (Name)
libpfm_intel_bdx_unc_cbo - support for Intel Broadwell Server C-
Box uncore PMU
Синопсис (Synopsis)
#include <perfmon/pfmlib.h>
PMU name: bdx_unc_cbo[0-21]
PMU desc: Intel Broadwell Server C-Box uncore PMU
Описание (Description)
The library supports the Intel Broadwell Server C-Box (coherency
engine) uncore PMU. This PMU model exists on various Broadwell
server models (79, 86) . There is one C-box PMU per physical
core. Therefore there are up to twenty-one identical C-Box PMU
instances numbered from 0 to 21. On dual-socket systems, the
number refers to the C-Box PMU on the socket where the program
runs. For instance, if running on CPU18, then bdx_unc_cbo0 refers
to the C-Box for physical core 0 on socket 1. Conversely, if
running on CPU0, then the same bdx_unc_cbo0 refers to the C-Box
for physical core 0 but on socket 0.
Each C-Box PMU implements 4 generic counters and two filter
registers used only with certain events and umasks.
Модификаторы (Modifiers)
The following modifiers are supported on Intel Broadwell C-Box
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 C-Box 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].
nf Node filter. Certain events, such as UNC_C_LLC_LOOKUP,
UNC_C_LLC_VICTIMS, provide a NID umask. Sometimes the NID
is combined with other filtering capabilities, such as
opcodes. The node filter is an 8-bit max bitmask. A node
corresponds to a processor socket. The legal values
therefore depend on the underlying hardware configuration.
For dual-socket systems, the bitmask has two valid bits
[0:1].
cf Core Filter. This is a 5-bit filter which is used to
filter based on physical core origin of the C-Box request.
Possible values are 0-63. If the filter is not specified,
then no filtering takes place. Bit 0-3 indicate the
physical core id and bit 4 filters on non thread-related
data.
tf Thread Filter. This is a 1-bit filter which is used to
filter C-Box requests based on logical processor (hyper-
thread) identification. Possibles values are 0-1. If the
filter is not specified, then no filtering takes place.
nc Non-Coherent. This is a 1-bit filter which is used to
filter C-Box requests only for the TOR_INSERTS and
TOR_OCCUPANCY umasks using the OPCODE matcher. If the
filter is not specified, then no filtering takes place.
isoc Isochronous. This is a 1-bit filter which is used to
filter C-Box requests only for the TOR_INSERTS and
TOR_OCCUPANCY umasks using the OPCODE matcher. If the
filter is not specified, then no filtering takes place.
Фильтрация кодов операций (Opcode filtering)
Certain events, such as UNC_C_TOR_INSERTS supports opcode
matching on the C-BOX transaction type. To use this feature,
first an opcode matching umask must be selected, e.g.,
MISS_OPCODE. Second, the opcode to match on must be selected via
a second umask among the OPC_* umasks. For instance,
UNC_C_TOR_INSERTS:OPCODE:OPC_RFO, counts the number of TOR
insertions for RFO transactions.
Opcode matching may be combined with node filtering with certain
umasks. In general, the filtering support is encoded into the
umask name, e.g., NID_OPCODE supports both node and opcode
filtering. For instance,
UNC_C_TOR_INSERTS:NID_OPCODE:OPC_RFO:nf=1.
