Linux Perf
EventClass.py
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1 # EventClass.py
2 # SPDX-License-Identifier: GPL-2.0
3 #
4 # This is a library defining some events types classes, which could
5 # be used by other scripts to analyzing the perf samples.
6 #
7 # Currently there are just a few classes defined for examples,
8 # PerfEvent is the base class for all perf event sample, PebsEvent
9 # is a HW base Intel x86 PEBS event, and user could add more SW/HW
10 # event classes based on requirements.
11 
12 import struct
13 
14 # Event types, user could add more here
15 EVTYPE_GENERIC = 0
16 EVTYPE_PEBS = 1 # Basic PEBS event
17 EVTYPE_PEBS_LL = 2 # PEBS event with load latency info
18 EVTYPE_IBS = 3
19 
20 #
21 # Currently we don't have good way to tell the event type, but by
22 # the size of raw buffer, raw PEBS event with load latency data's
23 # size is 176 bytes, while the pure PEBS event's size is 144 bytes.
24 #
25 def create_event(name, comm, dso, symbol, raw_buf):
26  if (len(raw_buf) == 144):
27  event = PebsEvent(name, comm, dso, symbol, raw_buf)
28  elif (len(raw_buf) == 176):
29  event = PebsNHM(name, comm, dso, symbol, raw_buf)
30  else:
31  event = PerfEvent(name, comm, dso, symbol, raw_buf)
32 
33  return event
34 
35 class PerfEvent(object):
36  event_num = 0
37  def __init__(self, name, comm, dso, symbol, raw_buf, ev_type=EVTYPE_GENERIC):
38  self.name = name
39  self.comm = comm
40  self.dso = dso
41  self.symbol = symbol
42  self.raw_buf = raw_buf
43  self.ev_type = ev_type
44  PerfEvent.event_num += 1
45 
46  def show(self):
47  print "PMU event: name=%12s, symbol=%24s, comm=%8s, dso=%12s" % (self.name, self.symbol, self.comm, self.dso)
48 
49 #
50 # Basic Intel PEBS (Precise Event-based Sampling) event, whose raw buffer
51 # contains the context info when that event happened: the EFLAGS and
52 # linear IP info, as well as all the registers.
53 #
55  pebs_num = 0
56  def __init__(self, name, comm, dso, symbol, raw_buf, ev_type=EVTYPE_PEBS):
57  tmp_buf=raw_buf[0:80]
58  flags, ip, ax, bx, cx, dx, si, di, bp, sp = struct.unpack('QQQQQQQQQQ', tmp_buf)
59  self.flags = flags
60  self.ip = ip
61  self.ax = ax
62  self.bx = bx
63  self.cx = cx
64  self.dx = dx
65  self.si = si
66  self.di = di
67  self.bp = bp
68  self.sp = sp
69 
70  PerfEvent.__init__(self, name, comm, dso, symbol, raw_buf, ev_type)
71  PebsEvent.pebs_num += 1
72  del tmp_buf
73 
74 #
75 # Intel Nehalem and Westmere support PEBS plus Load Latency info which lie
76 # in the four 64 bit words write after the PEBS data:
77 # Status: records the IA32_PERF_GLOBAL_STATUS register value
78 # DLA: Data Linear Address (EIP)
79 # DSE: Data Source Encoding, where the latency happens, hit or miss
80 # in L1/L2/L3 or IO operations
81 # LAT: the actual latency in cycles
82 #
84  pebs_nhm_num = 0
85  def __init__(self, name, comm, dso, symbol, raw_buf, ev_type=EVTYPE_PEBS_LL):
86  tmp_buf=raw_buf[144:176]
87  status, dla, dse, lat = struct.unpack('QQQQ', tmp_buf)
88  self.status = status
89  self.dla = dla
90  self.dse = dse
91  self.lat = lat
92 
93  PebsEvent.__init__(self, name, comm, dso, symbol, raw_buf, ev_type)
94  PebsNHM.pebs_nhm_num += 1
95  del tmp_buf
def create_event(name, comm, dso, symbol, raw_buf)
Definition: EventClass.py:25
def __init__(self, name, comm, dso, symbol, raw_buf, ev_type=EVTYPE_GENERIC)
Definition: EventClass.py:37
def __init__(self, name, comm, dso, symbol, raw_buf, ev_type=EVTYPE_PEBS_LL)
Definition: EventClass.py:85
def __init__(self, name, comm, dso, symbol, raw_buf, ev_type=EVTYPE_PEBS)
Definition: EventClass.py:56