1LIBPFM(3) Linux Programmer's Manual LIBPFM(3)
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6 libpfm_intel_snbep_unc_ubo - support for Intel Sandy Bridge-EP U-Box
7 uncore PMU
8
10 #include <perfmon/pfmlib.h>
11 PMU name: snbep_unc_ubo
13 PMU desc: Intel Sandy Bridge-EP U-Box uncore PMU
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17 The library supports the Intel Sandy Bridge system configuration unit
18 (U-Box) uncore PMU. This PMU model only exists on Sandy Bridge model
19 45. There is only one U-Box PMU per processor socket.
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23 The following modifiers are supported on Intel Sandy Bridge U-Box
24 uncore PMU:
25 i Invert the meaning of the event. The counter will now count HA
27 cycles in which the event is not occurring. This is a boolean
28 modifier
29 e Enable edge detection, i.e., count only when there is a state
31 transition from no occurrence of the event to at least one
32 occurrence. This modifier must be combined with a threshold mod‐
33 ifier (t) with a value greater or equal to one. This is a bool‐
34 ean modifier.
35 t Set the threshold value. When set to a non-zero value, the
37 counter counts the number of HA cycles in which the number of
38 occurrences of the event is greater or equal to the threshold.
39 This is an integer modifier with values in the range [0:15].
40 oi Invert the meaning of the occupancy event POWER_STATE_OCCUPANCY.
42 The counter will now count PCU cycles in which the event is not
43 occurring. This is a boolean modifier
44 oe Enable edge detection for the occupancy event POWER_STATE_OCCU‐
46 PANCY. The event now counts only when there is a state transi‐
47 tion from no occurrence of the event to at least one occurrence.
48 This modifier must be combined with a threshold modifier (t)
49 with a value greater or equal to one. This is a boolean modi‐
50 fier.
51 ff Enable frequency band filtering. This modifier applies only to
54 the UNC_P_FREQ_BANDx_CYCLES events, where x is [0-3]. The modi‐
55 fiers expects an integer in the range [0-255]. The value is
56 interpreted as a frequency value to be multiplied by 100Mhz.
57 Thus if the value is 32, then all cycles where the processor is
58 running at 3.2GHz and more are counted.
59
62 There are 3 events which support frequency band filtering, namely,
63 UNC_P_FREQ_BAND0_CYCLES, UNC_P_FREQ_BAND1_CYCLES,
64 UNC_P_FREQ_BAND2_CYCLES, UNC_P_FREQ_BAND3_CYCLES. The frequency filter
65 (available via the ff modifier) is stored into a PMU shared register
66 which hold all 4 possible frequency bands, one per event. However, the
67 library generate the encoding for each event individually because it
68 processes events one at a time. The caller or the underlying kernel
69 interface may have to merge the band filter settings to program the
70 filter register properly.
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74 Stephane Eranian <eranian@gmail.com>
75 August, 2012 LIBPFM(3)