1
2 The contents of this directory allow users to
3 CPUs by their symbolic names rather than raw e
4
5 The main program in this directory, is the 'je
6 executed _BEFORE_ the perf binary itself is bu
7
8 The 'jevents' program tries to locate and proc
9 tree tools/perf/pmu-events/arch/foo.
10
11 - Regular files with '.json' extension
12 JSON files, each of which describes
13
14 - The CSV file that maps a specific CP
15 be named 'mapfile.csv' (see below fo
16
17 - Directories are traversed, but all o
18
19 - To reduce JSON event duplication per
20 use "ArchStdEvent" keyword to derefe
21 events", defined in architecture sta
22 Architecture standard JSONs must be
23 folder. Matching is based on the "Ev
24
25 The PMU events supported by a CPU model are ex
26 such as Pipelining, Cache, Memory, Floating-po
27 should be placed in a separate JSON file - whe
28 the topic. Eg: "Floating-point.json".
29
30 All the topic JSON files for a CPU model/famil
31 sub directory. Thus for the Silvermont X86 CPU
32
33 $ ls tools/perf/pmu-events/arch/x86/si
34 cache.json memory.json virtual-
35 frontend.json pipeline.json
36
37 The JSONs folder for a CPU model/family may be
38 folder, or may be placed in a vendor sub-folde
39 for instances where the arch and vendor are no
40
41 Using the JSON files and the mapfile, 'jevents
42 'pmu-events.c', which encodes the two sets of
43
44 - Set of 'PMU events tables' for all k
45 (one table like the following, per J
46 is derived from JSON file name, 'pow
47
48 struct pmu_event pme_power8[]
49
50 ...
51
52 {
53 .name = "pm_1p
54 .event = "even
55 .desc = "1 or
56 },
57
58 ...
59 }
60
61 - A 'mapping table' that maps each CPU
62 'PMU events table'
63
64 struct pmu_events_map pmu_even
65 {
66 .cpuid = "004b0000",
67 .version = "1",
68 .type = "core",
69 .table = pme_power8
70 },
71 ...
72
73 };
74
75 After the 'pmu-events.c' is generated, it is c
76 'pmu-events.o' is added to 'libperf.a' which i
77
78 NOTES:
79 1. Several CPUs can support same set o
80 JSON file. Hence several entries in
81 to a single 'PMU events table'.
82
83 2. The 'pmu-events.h' has an extern de
84 and the generated 'pmu-events.c' de
85
86 3. _All_ known CPU tables for architec
87 binary.
88
89 At run time, perf determines the actual CPU it
90 matching events table and builds aliases for t
91 users to specify events by their name:
92
93 $ perf stat -e pm_1plus_ppc_cmpl sleep
94
95 where 'pm_1plus_ppc_cmpl' is a Power8 PMU even
96
97 However some errors in processing may cause th
98
99 Mapfile format
100 ===============
101
102 The mapfile enables multiple CPU models to sha
103 It is required even if such mapping is 1:1.
104
105 The mapfile.csv format is expected to be:
106
107 Header line
108 CPUID,Version,Dir/path/name,Type
109
110 where:
111
112 Comma:
113 is the required field delimite
114 have commas within them).
115
116 Comments:
117 Lines in which the first chara
118 are ignored.
119
120 Header line
121 The header line is the first l
122 always _IGNORED_. It can be em
123
124 CPUID:
125 CPUID is an arch-specific char
126 to identify CPU (and associate
127 it supports). Multiple CPUIDS
128 File/path/name.json.
129
130 Example:
131 CPUID == 'GenuineIntel
132 CPUID == '004b0100' (P
133 Version:
134 is the Version of the mapfile.
135
136 Dir/path/name:
137 is the pathname to the directo
138 files, relative to the directo
139
140 Type:
141 indicates whether the events a
142
143
144 Eg:
145
146 $ grep silvermont tools/perf/pmu-event
147 GenuineIntel-6-37,v13,silvermont,core
148 GenuineIntel-6-4D,v13,silvermont,core
149 GenuineIntel-6-4C,v13,silvermont,core
150
151 i.e the three CPU models use the JSON
152 in the directory 'tools/perf/pmu-event
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.