1LIBPFM(3)                  Linux Programmer's Manual                 LIBPFM(3)
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NAME

6       libpfm_intel_hsw - support for Intel Haswell core PMU
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SYNOPSIS

9       #include <perfmon/pfmlib.h>
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11       PMU name: hsw
12       PMU desc: Intel Haswell
13       PMU name: hsw_ep
14       PMU desc: Intel Haswell-EP
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DESCRIPTION

18       The  library  supports  the  Intel  Haswell and Haswell-EP core PMU. It
19       should be noted that this PMU model only covers each core's PMU and not
20       the socket level PMU.
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22       On  Haswell, the number of generic counters depends on the Hyperthread‐
23       ing (HT) mode.  When HT is on, then only 4 generic counters are  avail‐
24       able.  When  HT  is  off,  then  8  generic counters are available. The
25       pfm_get_pmu_info() function returns the maximum number of generic coun‐
26       ters in num_cntrs.
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MODIFIERS

30       The following modifiers are supported on Intel Haswell processors:
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32       u      Measure  at  user level which includes privilege levels 1, 2, 3.
33              This corresponds to PFM_PLM3.  This is a boolean modifier.
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35       k      Measure at kernel level which includes privilege level  0.  This
36              corresponds to PFM_PLM0.  This is a boolean modifier.
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38       i      Invert  the  meaning  of  the  event. The counter will now count
39              cycles in which the event is not occurring. This  is  a  boolean
40              modifier
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42       e      Enable  edge  detection,  i.e., count only when there is a state
43              transition from no occurrence of  the  event  to  at  least  one
44              occurrence.  This  modifier must be combined with a counter mask
45              modifier (m) with a value greater or equal to one.   This  is  a
46              boolean modifier.
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48       c      Set  the  counter  mask value. The mask acts as a threshold. The
49              counter will count the number of cycles in which the  number  of
50              occurrences  of  the event is greater or equal to the threshold.
51              This is an integer modifier with values in the range [0:255].
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53       t      Measure on both threads at the same time assuming  hyper-thread‐
54              ing is enabled. This is a boolean modifier.
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56       ldlat  Pass  a  latency threshold to the MEM_TRANS_RETIRED:LOAD_LATENCY
57              event.  This is an integer attribute that must be in  the  range
58              [3:65535].  It  is required for this event.  Note that the event
59              must be used with precise sampling (PEBS).
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61       intx   Monitor the event only when  executing  inside  a  transactional
62              memory region (in tx). Event does not count otherwise. This is a
63              boolean modifiers. Default value is 0.
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65       intxcp Do not count occurrences of the event when they  are  inside  an
66              aborted transactional memory region. This is a boolean modifier.
67              Default value is 0.
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OFFCORE_RESPONSE events

71       Intel Haswell provides two offcore_response  events.  They  are  called
72       OFFCORE_RESPONSE_0 and OFFCORE_RESPONSE_1.
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74       Those  events  need special treatment in the performance monitoring in‐
75       frastructure because each event uses an extra register  to  store  some
76       settings.  Thus, in case multiple offcore_response events are monitored
77       simultaneously, the kernel needs to manage the sharing  of  that  extra
78       register.
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80       The  offcore_response  events  are  exposed  as  a normal events by the
81       library. The extra settings are exposed as regular umasks. The  library
82       takes  care  of  encoding the events according to the underlying kernel
83       interface.
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85       On Intel  Haswell,  the  umasks  are  divided  into  three  categories:
86       request,  supplier  and snoop. The user must provide at least one umask
87       for each category. The categories are shown in the umask descriptions.
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89       There is also the special response umask called ANY_RESPONSE. When this
90       umask is used then it overrides any supplier and snoop umasks. In other
91       words, users can specify either ANY_RESPONSE  OR  any  combinations  of
92       supplier + snoops.
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94       In  case  no  supplier  or  snoop is specified, the library defaults to
95       using ANY_RESPONSE.
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97       For instance, the following are valid event selections:
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99       OFFCORE_RESPONSE_0:DMND_DATA_RD:ANY_RESPONSE
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101       OFFCORE_RESPONSE_0:ANY_REQUEST
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103       OFFCORE_RESPONSE_0:ANY_RFO:LLC_HITM:SNOOP_ANY
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106       But the following are illegal:
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109       OFFCORE_RESPONSE_0:ANY_RFO:LLC_HITM:ANY_RESPONSE
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111       OFFCORE_RESPONSE_0:ANY_RFO:LLC_HITM:SNOOP_ANY:ANY_RESPONSE
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AUTHORS

115       Stephane Eranian <eranian@gmail.com>
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119                                  April, 2013                        LIBPFM(3)
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