https://github.com/torvalds/linux
Tip revision: b90cb1053190353cc30f0fef0ef1f378ccc063c5 authored by Linus Torvalds on 28 August 2022, 22:05:29 UTC
Linux 6.0-rc3
Linux 6.0-rc3
Tip revision: b90cb10
perf-lock.txt
perf-lock(1)
============
NAME
----
perf-lock - Analyze lock events
SYNOPSIS
--------
[verse]
'perf lock' {record|report|script|info|contention}
DESCRIPTION
-----------
You can analyze various lock behaviours
and statistics with this 'perf lock' command.
'perf lock record <command>' records lock events
between start and end <command>. And this command
produces the file "perf.data" which contains tracing
results of lock events.
'perf lock report' reports statistical data.
'perf lock script' shows raw lock events.
'perf lock info' shows metadata like threads or addresses
of lock instances.
'perf lock contention' shows contention statistics.
COMMON OPTIONS
--------------
-i::
--input=<file>::
Input file name. (default: perf.data unless stdin is a fifo)
-v::
--verbose::
Be more verbose (show symbol address, etc).
-D::
--dump-raw-trace::
Dump raw trace in ASCII.
-f::
--force::
Don't complain, do it.
--vmlinux=<file>::
vmlinux pathname
--kallsyms=<file>::
kallsyms pathname
REPORT OPTIONS
--------------
-k::
--key=<value>::
Sorting key. Possible values: acquired (default), contended,
avg_wait, wait_total, wait_max, wait_min.
-F::
--field=<value>::
Output fields. By default it shows all the fields but users can
customize that using this. Possible values: acquired, contended,
avg_wait, wait_total, wait_max, wait_min.
-c::
--combine-locks::
Merge lock instances in the same class (based on name).
-t::
--threads::
The -t option is to show per-thread lock stat like below:
$ perf lock report -t -F acquired,contended,avg_wait
Name acquired contended avg wait (ns)
perf 240569 9 5784
swapper 106610 19 543
:15789 17370 2 14538
ContainerMgr 8981 6 874
sleep 5275 1 11281
ContainerThread 4416 4 944
RootPressureThr 3215 5 1215
rcu_preempt 2954 0 0
ContainerMgr 2560 0 0
unnamed 1873 0 0
EventManager_De 1845 1 636
futex-default-S 1609 0 0
INFO OPTIONS
------------
-t::
--threads::
dump thread list in perf.data
-m::
--map::
dump map of lock instances (address:name table)
CONTENTION OPTIONS
--------------
-k::
--key=<value>::
Sorting key. Possible values: contended, wait_total (default),
wait_max, wait_min, avg_wait.
-F::
--field=<value>::
Output fields. By default it shows all but the wait_min fields
and users can customize that using this. Possible values:
contended, wait_total, wait_max, wait_min, avg_wait.
-t::
--threads::
Show per-thread lock contention stat
-b::
--use-bpf::
Use BPF program to collect lock contention stats instead of
using the input data.
-a::
--all-cpus::
System-wide collection from all CPUs.
-C::
--cpu::
Collect samples only on the list of CPUs provided. Multiple CPUs can be
provided as a comma-separated list with no space: 0,1. Ranges of CPUs
are specified with -: 0-2. Default is to monitor all CPUs.
-p::
--pid=::
Record events on existing process ID (comma separated list).
--tid=::
Record events on existing thread ID (comma separated list).
--map-nr-entries::
Maximum number of BPF map entries (default: 10240).
SEE ALSO
--------
linkperf:perf[1]