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