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