1 perf-lock(1) 1 perf-lock(1)
2 ============ 2 ============
3 3
4 NAME 4 NAME
5 ---- 5 ----
6 perf-lock - Analyze lock events 6 perf-lock - Analyze lock events
7 7
8 SYNOPSIS 8 SYNOPSIS
9 -------- 9 --------
10 [verse] 10 [verse]
11 'perf lock' {record|report|script|info|content 11 'perf lock' {record|report|script|info|contention}
12 12
13 DESCRIPTION 13 DESCRIPTION
14 ----------- 14 -----------
15 You can analyze various lock behaviours 15 You can analyze various lock behaviours
16 and statistics with this 'perf lock' command. 16 and statistics with this 'perf lock' command.
17 17
18 'perf lock record <command>' records lock ev 18 'perf lock record <command>' records lock events
19 between start and end <command>. And this co 19 between start and end <command>. And this command
20 produces the file "perf.data" which contains 20 produces the file "perf.data" which contains tracing
21 results of lock events. 21 results of lock events.
22 22
23 'perf lock report' reports statistical data. 23 'perf lock report' reports statistical data.
24 24
25 'perf lock script' shows raw lock events. 25 'perf lock script' shows raw lock events.
26 26
27 'perf lock info' shows metadata like threads 27 'perf lock info' shows metadata like threads or addresses
28 of lock instances. 28 of lock instances.
29 29
30 'perf lock contention' shows contention stat 30 'perf lock contention' shows contention statistics.
31 31
32 COMMON OPTIONS 32 COMMON OPTIONS
33 -------------- 33 --------------
34 34
35 -i:: 35 -i::
36 --input=<file>:: 36 --input=<file>::
37 Input file name. (default: perf.data u 37 Input file name. (default: perf.data unless stdin is a fifo)
38 38
39 --output=<file>:: <<
40 Output file name for perf lock content <<
41 <<
42 -v:: 39 -v::
43 --verbose:: 40 --verbose::
44 Be more verbose (show symbol address, 41 Be more verbose (show symbol address, etc).
45 42
46 -q:: 43 -q::
47 --quiet:: 44 --quiet::
48 Do not show any warnings or messages. 45 Do not show any warnings or messages. (Suppress -v)
49 46
50 -D:: 47 -D::
51 --dump-raw-trace:: 48 --dump-raw-trace::
52 Dump raw trace in ASCII. 49 Dump raw trace in ASCII.
53 50
54 -f:: 51 -f::
55 --force:: 52 --force::
56 Don't complain, do it. 53 Don't complain, do it.
57 54
58 --vmlinux=<file>:: 55 --vmlinux=<file>::
59 vmlinux pathname 56 vmlinux pathname
60 57
61 --kallsyms=<file>:: 58 --kallsyms=<file>::
62 kallsyms pathname 59 kallsyms pathname
63 60
64 61
65 REPORT OPTIONS 62 REPORT OPTIONS
66 -------------- 63 --------------
67 64
68 -k:: 65 -k::
69 --key=<value>:: 66 --key=<value>::
70 Sorting key. Possible values: acquired 67 Sorting key. Possible values: acquired (default), contended,
71 avg_wait, wait_total, wait_max, wait_m 68 avg_wait, wait_total, wait_max, wait_min.
72 69
73 -F:: 70 -F::
74 --field=<value>:: 71 --field=<value>::
75 Output fields. By default it shows all 72 Output fields. By default it shows all the fields but users can
76 customize that using this. Possible v 73 customize that using this. Possible values: acquired, contended,
77 avg_wait, wait_total, wait_max, wait_m 74 avg_wait, wait_total, wait_max, wait_min.
78 75
79 -c:: 76 -c::
80 --combine-locks:: 77 --combine-locks::
81 Merge lock instances in the same class 78 Merge lock instances in the same class (based on name).
82 79
83 -t:: 80 -t::
84 --threads:: 81 --threads::
85 The -t option is to show per-thread lock s 82 The -t option is to show per-thread lock stat like below:
86 83
87 $ perf lock report -t -F acquired,conten 84 $ perf lock report -t -F acquired,contended,avg_wait
88 85
89 Name acquired contended 86 Name acquired contended avg wait (ns)
90 87
91 perf 240569 9 88 perf 240569 9 5784
92 swapper 106610 19 89 swapper 106610 19 543
93 :15789 17370 2 90 :15789 17370 2 14538
94 ContainerMgr 8981 6 91 ContainerMgr 8981 6 874
95 sleep 5275 1 92 sleep 5275 1 11281
96 ContainerThread 4416 4 93 ContainerThread 4416 4 944
97 RootPressureThr 3215 5 94 RootPressureThr 3215 5 1215
98 rcu_preempt 2954 0 95 rcu_preempt 2954 0 0
99 ContainerMgr 2560 0 96 ContainerMgr 2560 0 0
100 unnamed 1873 0 97 unnamed 1873 0 0
101 EventManager_De 1845 1 98 EventManager_De 1845 1 636
102 futex-default-S 1609 0 99 futex-default-S 1609 0 0
103 100
104 -E:: 101 -E::
105 --entries=<value>:: 102 --entries=<value>::
106 Display this many entries. 103 Display this many entries.
107 104
108 105
109 INFO OPTIONS 106 INFO OPTIONS
110 ------------ 107 ------------
111 108
112 -t:: 109 -t::
113 --threads:: 110 --threads::
114 dump only the thread list in perf.data !! 111 dump thread list in perf.data
115 112
116 -m:: 113 -m::
117 --map:: 114 --map::
118 dump only the map of lock instances (a !! 115 dump map of lock instances (address:name table)
119 116
120 117
121 CONTENTION OPTIONS 118 CONTENTION OPTIONS
122 ------------------ !! 119 --------------
123 120
124 -k:: 121 -k::
125 --key=<value>:: 122 --key=<value>::
126 Sorting key. Possible values: contende 123 Sorting key. Possible values: contended, wait_total (default),
127 wait_max, wait_min, avg_wait. 124 wait_max, wait_min, avg_wait.
128 125
129 -F:: 126 -F::
130 --field=<value>:: 127 --field=<value>::
131 Output fields. By default it shows all 128 Output fields. By default it shows all but the wait_min fields
132 and users can customize that using thi 129 and users can customize that using this. Possible values:
133 contended, wait_total, wait_max, wait_ 130 contended, wait_total, wait_max, wait_min, avg_wait.
134 131
135 -t:: 132 -t::
136 --threads:: 133 --threads::
137 Show per-thread lock contention stat 134 Show per-thread lock contention stat
138 135
139 -b:: 136 -b::
140 --use-bpf:: 137 --use-bpf::
141 Use BPF program to collect lock conten 138 Use BPF program to collect lock contention stats instead of
142 using the input data. 139 using the input data.
143 140
144 -a:: 141 -a::
145 --all-cpus:: 142 --all-cpus::
146 System-wide collection from all CPUs. 143 System-wide collection from all CPUs.
147 144
148 -C:: 145 -C::
149 --cpu=<value>:: 146 --cpu=<value>::
150 Collect samples only on the list of CP 147 Collect samples only on the list of CPUs provided. Multiple CPUs can be
151 provided as a comma-separated list wit 148 provided as a comma-separated list with no space: 0,1. Ranges of CPUs
152 are specified with -: 0-2. Default is 149 are specified with -: 0-2. Default is to monitor all CPUs.
153 150
154 -p:: 151 -p::
155 --pid=<value>:: 152 --pid=<value>::
156 Record events on existing process ID ( 153 Record events on existing process ID (comma separated list).
157 154
158 --tid=<value>:: 155 --tid=<value>::
159 Record events on existing thread ID (c 156 Record events on existing thread ID (comma separated list).
160 157
161 -M:: 158 -M::
162 --map-nr-entries=<value>:: 159 --map-nr-entries=<value>::
163 Maximum number of BPF map entries (def 160 Maximum number of BPF map entries (default: 16384).
164 This will be aligned to a power of 2. 161 This will be aligned to a power of 2.
165 162
166 --max-stack=<value>:: 163 --max-stack=<value>::
167 Maximum stack depth when collecting lo 164 Maximum stack depth when collecting lock contention (default: 8).
168 165
169 --stack-skip=<value>:: 166 --stack-skip=<value>::
170 Number of stack depth to skip when fin 167 Number of stack depth to skip when finding a lock caller (default: 3).
171 168
172 -E:: 169 -E::
173 --entries=<value>:: 170 --entries=<value>::
174 Display this many entries. 171 Display this many entries.
175 172
176 -l:: 173 -l::
177 --lock-addr:: 174 --lock-addr::
178 Show lock contention stat by address 175 Show lock contention stat by address
179 176
180 -o:: 177 -o::
181 --lock-owner:: 178 --lock-owner::
182 Show lock contention stat by owners. 179 Show lock contention stat by owners. Implies --threads and
183 requires --use-bpf. 180 requires --use-bpf.
184 181
185 -Y:: 182 -Y::
186 --type-filter=<value>:: 183 --type-filter=<value>::
187 Show lock contention only for given lo 184 Show lock contention only for given lock types (comma separated list).
188 Available values are: 185 Available values are:
189 semaphore, spinlock, rwlock, rwlock: 186 semaphore, spinlock, rwlock, rwlock:R, rwlock:W, rwsem, rwsem:R, rwsem:W,
190 rtmutex, rwlock-rt, rwlock-rt:R, rwl 187 rtmutex, rwlock-rt, rwlock-rt:R, rwlock-rt:W, pcpu-sem, pcpu-sem:R, pcpu-sem:W,
191 mutex 188 mutex
192 189
193 Note that RW-variant of locks have :R 190 Note that RW-variant of locks have :R and :W suffix. Names without the
194 suffix are shortcuts for the both vari 191 suffix are shortcuts for the both variants. Ex) rwsem = rwsem:R + rwsem:W.
195 192
196 -L:: 193 -L::
197 --lock-filter=<value>:: 194 --lock-filter=<value>::
198 Show lock contention only for given lo 195 Show lock contention only for given lock addresses or names (comma separated list).
199 196
200 -S:: 197 -S::
201 --callstack-filter=<value>:: 198 --callstack-filter=<value>::
202 Show lock contention only if the calls 199 Show lock contention only if the callstack contains the given string.
203 Note that it matches the substring so 200 Note that it matches the substring so 'rq' would match both 'raw_spin_rq_lock'
204 and 'irq_enter_rcu'. 201 and 'irq_enter_rcu'.
205 <<
206 -x:: <<
207 --field-separator=<SEP>:: <<
208 Show results using a CSV-style output <<
209 into spreadsheets. Columns are separat <<
210 <<
211 --lock-cgroup:: <<
212 Show lock contention stat by cgroup. <<
213 <<
214 -G:: <<
215 --cgroup-filter=<value>:: <<
216 Show lock contention only in the given <<
217 202
218 203
219 SEE ALSO 204 SEE ALSO
220 -------- 205 --------
221 linkperf:perf[1] 206 linkperf:perf[1]
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