1perf-lock(1) 2============ 3 4NAME 5---- 6perf-lock - Analyze lock events 7 8SYNOPSIS 9-------- 10[verse] 11'perf lock' {record|report|script|info|contention} 12 13DESCRIPTION 14----------- 15You can analyze various lock behaviours 16and statistics with this 'perf lock' command. 17 18 'perf lock record <command>' records lock events 19 between start and end <command>. And this command 20 produces the file "perf.data" which contains tracing 21 results of lock events. 22 23 'perf lock report' reports statistical data. 24 25 'perf lock script' shows raw lock events. 26 27 'perf lock info' shows metadata like threads or addresses 28 of lock instances. 29 30 'perf lock contention' shows contention statistics. 31 32COMMON OPTIONS 33-------------- 34 35-i:: 36--input=<file>:: 37 Input file name. (default: perf.data unless stdin is a fifo) 38 39--output=<file>:: 40 Output file name for perf lock contention and report. 41 42-v:: 43--verbose:: 44 Be more verbose (show symbol address, etc). 45 46-q:: 47--quiet:: 48 Do not show any warnings or messages. (Suppress -v) 49 50-D:: 51--dump-raw-trace:: 52 Dump raw trace in ASCII. 53 54-f:: 55--force:: 56 Don't complain, do it. 57 58--vmlinux=<file>:: 59 vmlinux pathname 60 61--kallsyms=<file>:: 62 kallsyms pathname 63 64 65REPORT OPTIONS 66-------------- 67 68-k:: 69--key=<value>:: 70 Sorting key. Possible values: acquired (default), contended, 71 avg_wait, wait_total, wait_max, wait_min. 72 73-F:: 74--field=<value>:: 75 Output fields. By default it shows all the fields but users can 76 customize that using this. Possible values: acquired, contended, 77 avg_wait, wait_total, wait_max, wait_min. 78 79-c:: 80--combine-locks:: 81 Merge lock instances in the same class (based on name). 82 83-t:: 84--threads:: 85 The -t option is to show per-thread lock stat like below: 86 87 $ perf lock report -t -F acquired,contended,avg_wait 88 89 Name acquired contended avg wait (ns) 90 91 perf 240569 9 5784 92 swapper 106610 19 543 93 :15789 17370 2 14538 94 ContainerMgr 8981 6 874 95 sleep 5275 1 11281 96 ContainerThread 4416 4 944 97 RootPressureThr 3215 5 1215 98 rcu_preempt 2954 0 0 99 ContainerMgr 2560 0 0 100 unnamed 1873 0 0 101 EventManager_De 1845 1 636 102 futex-default-S 1609 0 0 103 104-E:: 105--entries=<value>:: 106 Display this many entries. 107 108 109INFO OPTIONS 110------------ 111 112-t:: 113--threads:: 114 dump only the thread list in perf.data 115 116-m:: 117--map:: 118 dump only the map of lock instances (address:name table) 119 120 121CONTENTION OPTIONS 122------------------ 123 124-k:: 125--key=<value>:: 126 Sorting key. Possible values: contended, wait_total (default), 127 wait_max, wait_min, avg_wait. 128 129-F:: 130--field=<value>:: 131 Output fields. By default it shows all but the wait_min fields 132 and users can customize that using this. Possible values: 133 contended, wait_total, wait_max, wait_min, avg_wait. 134 135-t:: 136--threads:: 137 Show per-thread lock contention stat 138 139-b:: 140--use-bpf:: 141 Use BPF program to collect lock contention stats instead of 142 using the input data. 143 144-a:: 145--all-cpus:: 146 System-wide collection from all CPUs. 147 148-C:: 149--cpu=<value>:: 150 Collect samples only on the list of CPUs provided. Multiple CPUs can be 151 provided as a comma-separated list with no space: 0,1. Ranges of CPUs 152 are specified with -: 0-2. Default is to monitor all CPUs. 153 154-p:: 155--pid=<value>:: 156 Record events on existing process ID (comma separated list). 157 158--tid=<value>:: 159 Record events on existing thread ID (comma separated list). 160 161-M:: 162--map-nr-entries=<value>:: 163 Maximum number of BPF map entries (default: 16384). 164 This will be aligned to a power of 2. 165 166--max-stack=<value>:: 167 Maximum stack depth when collecting lock contention (default: 8). 168 169--stack-skip=<value>:: 170 Number of stack depth to skip when finding a lock caller (default: 3). 171 172-E:: 173--entries=<value>:: 174 Display this many entries. 175 176-l:: 177--lock-addr:: 178 Show lock contention stat by address 179 180-o:: 181--lock-owner:: 182 Show lock contention stat by owners. Implies --threads and 183 requires --use-bpf. 184 185-Y:: 186--type-filter=<value>:: 187 Show lock contention only for given lock types (comma separated list). 188 Available values are: 189 semaphore, spinlock, rwlock, rwlock:R, rwlock:W, rwsem, rwsem:R, rwsem:W, 190 rtmutex, rwlock-rt, rwlock-rt:R, rwlock-rt:W, pcpu-sem, pcpu-sem:R, pcpu-sem:W, 191 mutex 192 193 Note that RW-variant of locks have :R and :W suffix. Names without the 194 suffix are shortcuts for the both variants. Ex) rwsem = rwsem:R + rwsem:W. 195 196-L:: 197--lock-filter=<value>:: 198 Show lock contention only for given lock addresses or names (comma separated list). 199 200-S:: 201--callstack-filter=<value>:: 202 Show lock contention only if the callstack contains the given string. 203 Note that it matches the substring so 'rq' would match both 'raw_spin_rq_lock' 204 and 'irq_enter_rcu'. 205 206-x:: 207--field-separator=<SEP>:: 208 Show results using a CSV-style output to make it easy to import directly 209 into spreadsheets. Columns are separated by the string specified in SEP. 210 211--lock-cgroup:: 212 Show lock contention stat by cgroup. Requires --use-bpf. 213 214-G:: 215--cgroup-filter=<value>:: 216 Show lock contention only in the given cgroups (comma separated list). 217 218 219SEE ALSO 220-------- 221linkperf:perf[1] 222