1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
|
perf-list(1)
============
NAME
----
perf-list - List all symbolic event types
SYNOPSIS
--------
[verse]
'perf list' [hw|sw|cache|tracepoint|event_glob]
DESCRIPTION
-----------
This command displays the symbolic event types which can be selected in the
various perf commands with the -e option.
[[EVENT_MODIFIERS]]
EVENT MODIFIERS
---------------
Events can optionally have a modifer by appending a colon and one or
more modifiers. Modifiers allow the user to restrict the events to be
counted. The following modifiers exist:
u - user-space counting
k - kernel counting
h - hypervisor counting
G - guest counting (in KVM guests)
H - host counting (not in KVM guests)
p - precise level
The 'p' modifier can be used for specifying how precise the instruction
address should be. The 'p' modifier can be specified multiple times:
0 - SAMPLE_IP can have arbitrary skid
1 - SAMPLE_IP must have constant skid
2 - SAMPLE_IP requested to have 0 skid
3 - SAMPLE_IP must have 0 skid
For Intel systems precise event sampling is implemented with PEBS
which supports up to precise-level 2.
On AMD systems it is implemented using IBS (up to precise-level 2).
The precise modifier works with event types 0x76 (cpu-cycles, CPU
clocks not halted) and 0xC1 (micro-ops retired). Both events map to
IBS execution sampling (IBS op) with the IBS Op Counter Control bit
(IbsOpCntCtl) set respectively (see AMD64 Architecture Programmer’s
Manual Volume 2: System Programming, 13.3 Instruction-Based
Sampling). Examples to use IBS:
perf record -a -e cpu-cycles:p ... # use ibs op counting cycles
perf record -a -e r076:p ... # same as -e cpu-cycles:p
perf record -a -e r0C1:p ... # use ibs op counting micro-ops
RAW HARDWARE EVENT DESCRIPTOR
-----------------------------
Even when an event is not available in a symbolic form within perf right now,
it can be encoded in a per processor specific way.
For instance For x86 CPUs NNN represents the raw register encoding with the
layout of IA32_PERFEVTSELx MSRs (see [Intel® 64 and IA-32 Architectures Software Developer's Manual Volume 3B: System Programming Guide] Figure 30-1 Layout
of IA32_PERFEVTSELx MSRs) or AMD's PerfEvtSeln (see [AMD64 Architecture Programmer’s Manual Volume 2: System Programming], Page 344,
Figure 13-7 Performance Event-Select Register (PerfEvtSeln)).
Note: Only the following bit fields can be set in x86 counter
registers: event, umask, edge, inv, cmask. Esp. guest/host only and
OS/user mode flags must be setup using <<EVENT_MODIFIERS, EVENT
MODIFIERS>>.
Example:
If the Intel docs for a QM720 Core i7 describe an event as:
Event Umask Event Mask
Num. Value Mnemonic Description Comment
A8H 01H LSD.UOPS Counts the number of micro-ops Use cmask=1 and
delivered by loop stream detector invert to count
cycles
raw encoding of 0x1A8 can be used:
perf stat -e r1a8 -a sleep 1
perf record -e r1a8 ...
You should refer to the processor specific documentation for getting these
details. Some of them are referenced in the SEE ALSO section below.
OPTIONS
-------
Without options all known events will be listed.
To limit the list use:
. 'hw' or 'hardware' to list hardware events such as cache-misses, etc.
. 'sw' or 'software' to list software events such as context switches, etc.
. 'cache' or 'hwcache' to list hardware cache events such as L1-dcache-loads, etc.
. 'tracepoint' to list all tracepoint events, alternatively use
'subsys_glob:event_glob' to filter by tracepoint subsystems such as sched,
block, etc.
. If none of the above is matched, it will apply the supplied glob to all
events, printing the ones that match.
One or more types can be used at the same time, listing the events for the
types specified.
SEE ALSO
--------
linkperf:perf-stat[1], linkperf:perf-top[1],
linkperf:perf-record[1],
http://www.intel.com/Assets/PDF/manual/253669.pdf[Intel® 64 and IA-32 Architectures Software Developer's Manual Volume 3B: System Programming Guide],
http://support.amd.com/us/Processor_TechDocs/24593_APM_v2.pdf[AMD64 Architecture Programmer’s Manual Volume 2: System Programming]
|
