Documentation/ABI/testing/sysfs-bus-event_source-devices-events

   1 What:           /sys/devices/cpu/events/
   2                 /sys/devices/cpu/events/branch-misses
   3                 /sys/devices/cpu/events/cache-references
   4                 /sys/devices/cpu/events/cache-misses
   5                 /sys/devices/cpu/events/stalled-cycles-frontend
   6                 /sys/devices/cpu/events/branch-instructions
   7                 /sys/devices/cpu/events/stalled-cycles-backend
   8                 /sys/devices/cpu/events/instructions
   9                 /sys/devices/cpu/events/cpu-cycles
  10
  11 Date:           2013/01/08
  12
  13 Contact:        Linux kernel mailing list <linux-kernel@vger.kernel.org>
  14
  15 Description:    Generic performance monitoring events
  16
  17                 A collection of performance monitoring events that may be
  18                 supported by many/most CPUs. These events can be monitored
  19                 using the 'perf(1)' tool.
  20
  21                 The contents of each file would look like:
  22
  23                         event=0xNNNN
  24
  25                 where 'N' is a hex digit and the number '0xNNNN' shows the
  26                 "raw code" for the perf event identified by the file's
  27                 "basename".
  28
  29
  30 What: /sys/bus/event_source/devices/<pmu>/events/<event>
  31 Date: 2014/02/24
  32 Contact:        Linux kernel mailing list <linux-kernel@vger.kernel.org>
  33 Description:    Per-pmu performance monitoring events specific to the running system
  34
  35                 Each file (except for some of those with a '.' in them, '.unit'
  36                 and '.scale') in the 'events' directory describes a single
  37                 performance monitoring event supported by the <pmu>. The name
  38                 of the file is the name of the event.
  39
  40                 File contents:
  41
  42                         <term>[=<value>][,<term>[=<value>]]...
  43
  44                 Where <term> is one of the terms listed under
  45                 /sys/bus/event_source/devices/<pmu>/format/ and <value> is
  46                 a number is base-16 format with a '0x' prefix (lowercase only).
  47                 If a <term> is specified alone (without an assigned value), it
  48                 is implied that 0x1 is assigned to that <term>.
  49
  50                 Examples (each of these lines would be in a seperate file):
  51
  52                         event=0x2abc
  53                         event=0x423,inv,cmask=0x3
  54                         domain=0x1,offset=0x8,starting_index=0xffff
  55                         domain=0x1,offset=0x8,core=?
  56
  57                 Each of the assignments indicates a value to be assigned to a
  58                 particular set of bits (as defined by the format file
  59                 corresponding to the <term>) in the perf_event structure passed
  60                 to the perf_open syscall.
  61
  62                 In the case of the last example, a value replacing "?" would
  63                 need to be provided by the user selecting the particular event.
  64                 This is referred to as "event parameterization". Event
  65                 parameters have the format 'param=?'.
  66
  67 What: /sys/bus/event_source/devices/<pmu>/events/<event>.unit
  68 Date: 2014/02/24
  69 Contact:        Linux kernel mailing list <linux-kernel@vger.kernel.org>
  70 Description:    Perf event units
  71
  72                 A string specifying the English plural numerical unit that <event>
  73                 (once multiplied by <event>.scale) represents.
  74
  75                 Example:
  76
  77                         Joules
  78
  79 What: /sys/bus/event_source/devices/<pmu>/events/<event>.scale
  80 Date: 2014/02/24
  81 Contact:        Linux kernel mailing list <linux-kernel@vger.kernel.org>
  82 Description:    Perf event scaling factors
  83
  84                 A string representing a floating point value expressed in
  85                 scientific notation to be multiplied by the event count
  86                 recieved from the kernel to match the unit specified in the
  87                 <event>.unit file.
  88
  89                 Example:
  90
  91                         2.3283064365386962890625e-10
  92
  93                 This is provided to avoid performing floating point arithmetic
  94                 in the kernel.