1 perf-ftrace(1) 1 perf-ftrace(1)
2 ============== 2 ==============
3 3
4 NAME 4 NAME
5 ---- 5 ----
6 perf-ftrace - simple wrapper for kernel's ftra 6 perf-ftrace - simple wrapper for kernel's ftrace functionality
7 7
8 8
9 SYNOPSIS 9 SYNOPSIS
10 -------- 10 --------
11 [verse] 11 [verse]
12 'perf ftrace' {trace|latency|profile} <command 12 'perf ftrace' {trace|latency|profile} <command>
13 13
14 DESCRIPTION 14 DESCRIPTION
15 ----------- 15 -----------
16 The 'perf ftrace' command provides a collectio 16 The 'perf ftrace' command provides a collection of subcommands which use
17 kernel's ftrace infrastructure. 17 kernel's ftrace infrastructure.
18 18
19 'perf ftrace trace' is a simple wrapper of t 19 'perf ftrace trace' is a simple wrapper of the ftrace. It only supports
20 single thread tracing currently and just rea 20 single thread tracing currently and just reads trace_pipe in text and then
21 write it to stdout. 21 write it to stdout.
22 22
23 'perf ftrace latency' calculates execution l 23 'perf ftrace latency' calculates execution latency of a given function
24 (optionally with BPF) and display it as a hi 24 (optionally with BPF) and display it as a histogram.
25 25
26 'perf ftrace profile' show a execution profi 26 'perf ftrace profile' show a execution profile for each function including
27 total, average, max time and the number of c 27 total, average, max time and the number of calls.
28 28
29 The following options apply to perf ftrace. 29 The following options apply to perf ftrace.
30 30
31 COMMON OPTIONS 31 COMMON OPTIONS
32 -------------- 32 --------------
33 33
34 -p:: 34 -p::
35 --pid=:: 35 --pid=::
36 Trace on existing process id (comma se 36 Trace on existing process id (comma separated list).
37 37
38 --tid=:: 38 --tid=::
39 Trace on existing thread id (comma sep 39 Trace on existing thread id (comma separated list).
40 40
41 -a:: 41 -a::
42 --all-cpus:: 42 --all-cpus::
43 Force system-wide collection. Scripts 43 Force system-wide collection. Scripts run without a <command>
44 normally use -a by default, while scri 44 normally use -a by default, while scripts run with a <command>
45 normally don't - this option allows th 45 normally don't - this option allows the latter to be run in
46 system-wide mode. 46 system-wide mode.
47 47
48 -C:: 48 -C::
49 --cpu=:: 49 --cpu=::
50 Only trace for the list of CPUs provid 50 Only trace for the list of CPUs provided. Multiple CPUs can
51 be provided as a comma separated list 51 be provided as a comma separated list with no space like: 0,1.
52 Ranges of CPUs are specified with -: 0 52 Ranges of CPUs are specified with -: 0-2.
53 Default is to trace on all online CPUs 53 Default is to trace on all online CPUs.
54 54
55 -v:: 55 -v::
56 --verbose:: 56 --verbose::
57 Increase the verbosity level. 57 Increase the verbosity level.
58 58
59 59
60 OPTIONS for 'perf ftrace trace' 60 OPTIONS for 'perf ftrace trace'
61 ------------------------------- 61 -------------------------------
62 62
63 -t:: 63 -t::
64 --tracer=:: 64 --tracer=::
65 Tracer to use when neither -G nor -F o 65 Tracer to use when neither -G nor -F option is not
66 specified: function_graph or function. 66 specified: function_graph or function.
67 67
68 -F:: 68 -F::
69 --funcs:: 69 --funcs::
70 List available functions to trace. It 70 List available functions to trace. It accepts a pattern to
71 only list interested functions. 71 only list interested functions.
72 72
73 -D:: 73 -D::
74 --delay:: 74 --delay::
75 Time (ms) to wait before starting trac 75 Time (ms) to wait before starting tracing after program start.
76 76
77 -m:: 77 -m::
78 --buffer-size:: 78 --buffer-size::
79 Set the size of per-cpu tracing buffer 79 Set the size of per-cpu tracing buffer, <size> is expected to
80 be a number with appended unit charact 80 be a number with appended unit character - B/K/M/G.
81 81
82 --inherit:: 82 --inherit::
83 Trace children processes spawned by ou 83 Trace children processes spawned by our target.
84 84
85 -T:: 85 -T::
86 --trace-funcs=:: 86 --trace-funcs=::
87 Select function tracer and set functio 87 Select function tracer and set function filter on the given
88 function (or a glob pattern). Multiple 88 function (or a glob pattern). Multiple functions can be given
89 by using this option more than once. T 89 by using this option more than once. The function argument also
90 can be a glob pattern. It will be pass 90 can be a glob pattern. It will be passed to 'set_ftrace_filter'
91 in tracefs. 91 in tracefs.
92 92
93 -N:: 93 -N::
94 --notrace-funcs=:: 94 --notrace-funcs=::
95 Select function tracer and do not trac 95 Select function tracer and do not trace functions given by the
96 argument. Like -T option, this can be 96 argument. Like -T option, this can be used more than once to
97 specify multiple functions (or glob pa 97 specify multiple functions (or glob patterns). It will be
98 passed to 'set_ftrace_notrace' in trac 98 passed to 'set_ftrace_notrace' in tracefs.
99 99
100 --func-opts:: 100 --func-opts::
101 List of options allowed to set: 101 List of options allowed to set:
102 102
103 - call-graph - Display kernel stack 103 - call-graph - Display kernel stack trace for function tracer.
104 - irq-info - Display irq context i 104 - irq-info - Display irq context info for function tracer.
105 105
106 -G:: 106 -G::
107 --graph-funcs=:: 107 --graph-funcs=::
108 Select function_graph tracer and set g 108 Select function_graph tracer and set graph filter on the given
109 function (or a glob pattern). This is 109 function (or a glob pattern). This is useful to trace for
110 functions executed from the given func 110 functions executed from the given function. This can be used more
111 than once to specify multiple function 111 than once to specify multiple functions. It will be passed to
112 'set_graph_function' in tracefs. 112 'set_graph_function' in tracefs.
113 113
114 -g:: 114 -g::
115 --nograph-funcs=:: 115 --nograph-funcs=::
116 Select function_graph tracer and set g 116 Select function_graph tracer and set graph notrace filter on the
117 given function (or a glob pattern). Li 117 given function (or a glob pattern). Like -G option, this is useful
118 for the function_graph tracer only and 118 for the function_graph tracer only and disables tracing for function
119 executed from the given function. This 119 executed from the given function. This can be used more than once to
120 specify multiple functions. It will be 120 specify multiple functions. It will be passed to 'set_graph_notrace'
121 in tracefs. 121 in tracefs.
122 122
123 --graph-opts:: 123 --graph-opts::
124 List of options allowed to set: 124 List of options allowed to set:
125 125
126 - nosleep-time - Measure on-CPU time 126 - nosleep-time - Measure on-CPU time only for function_graph tracer.
127 - noirqs - Ignore functions th 127 - noirqs - Ignore functions that happen inside interrupt.
128 - verbose - Show process names, 128 - verbose - Show process names, PIDs, timestamps, etc.
129 - thresh=<n> - Setup trace duratio 129 - thresh=<n> - Setup trace duration threshold in microseconds.
130 - depth=<n> - Set max depth for f 130 - depth=<n> - Set max depth for function graph tracer to follow.
131 - tail - Print function name 131 - tail - Print function name at the end.
132 132
133 133
134 OPTIONS for 'perf ftrace latency' 134 OPTIONS for 'perf ftrace latency'
135 --------------------------------- 135 ---------------------------------
136 136
137 -T:: 137 -T::
138 --trace-funcs=:: 138 --trace-funcs=::
139 Set the function name to get the histo 139 Set the function name to get the histogram. Unlike perf ftrace trace,
140 it only allows single function to calc 140 it only allows single function to calculate the histogram.
141 141
142 -b:: 142 -b::
143 --use-bpf:: 143 --use-bpf::
144 Use BPF to measure function latency in 144 Use BPF to measure function latency instead of using the ftrace (it
145 uses function_graph tracer internally) 145 uses function_graph tracer internally).
146 146
147 -n:: 147 -n::
148 --use-nsec:: 148 --use-nsec::
149 Use nano-second instead of micro-secon 149 Use nano-second instead of micro-second as a base unit of the histogram.
150 150
151 151
152 OPTIONS for 'perf ftrace profile' 152 OPTIONS for 'perf ftrace profile'
153 --------------------------------- 153 ---------------------------------
154 154
155 -T:: 155 -T::
156 --trace-funcs=:: 156 --trace-funcs=::
157 Set function filter on the given funct 157 Set function filter on the given function (or a glob pattern).
158 Multiple functions can be given by usi 158 Multiple functions can be given by using this option more than once.
159 The function argument also can be a gl 159 The function argument also can be a glob pattern. It will be passed
160 to 'set_ftrace_filter' in tracefs. 160 to 'set_ftrace_filter' in tracefs.
161 161
162 -N:: 162 -N::
163 --notrace-funcs=:: 163 --notrace-funcs=::
164 Do not trace functions given by the ar 164 Do not trace functions given by the argument. Like -T option, this
165 can be used more than once to specify 165 can be used more than once to specify multiple functions (or glob
166 patterns). It will be passed to 'set_ 166 patterns). It will be passed to 'set_ftrace_notrace' in tracefs.
167 167
168 -G:: 168 -G::
169 --graph-funcs=:: 169 --graph-funcs=::
170 Set graph filter on the given function 170 Set graph filter on the given function (or a glob pattern). This is
171 useful to trace for functions executed 171 useful to trace for functions executed from the given function. This
172 can be used more than once to specify 172 can be used more than once to specify multiple functions. It will be
173 passed to 'set_graph_function' in trac 173 passed to 'set_graph_function' in tracefs.
174 174
175 -g:: 175 -g::
176 --nograph-funcs=:: 176 --nograph-funcs=::
177 Set graph notrace filter on the given 177 Set graph notrace filter on the given function (or a glob pattern).
178 Like -G option, this is useful for the 178 Like -G option, this is useful for the function_graph tracer only and
179 disables tracing for function executed 179 disables tracing for function executed from the given function. This
180 can be used more than once to specify 180 can be used more than once to specify multiple functions. It will be
181 passed to 'set_graph_notrace' in trace 181 passed to 'set_graph_notrace' in tracefs.
182 182
183 -m:: 183 -m::
184 --buffer-size:: 184 --buffer-size::
185 Set the size of per-cpu tracing buffer 185 Set the size of per-cpu tracing buffer, <size> is expected to
186 be a number with appended unit charact 186 be a number with appended unit character - B/K/M/G.
187 187
188 -s:: 188 -s::
189 --sort=:: 189 --sort=::
190 Sort the result by the given field. A 190 Sort the result by the given field. Available values are:
191 total, avg, max, count, name. Default 191 total, avg, max, count, name. Default is 'total'.
192 192
193 193
194 SEE ALSO 194 SEE ALSO
195 -------- 195 --------
196 linkperf:perf-record[1], linkperf:perf-trace[1 196 linkperf:perf-record[1], linkperf:perf-trace[1]
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.