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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
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Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
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+perf-kowrk(1)
+=============
+
+NAME
+----
+perf-kwork - Tool to trace/measure kernel work properties (latencies)
+
+SYNOPSIS
+--------
+[verse]
+'perf kwork' {record|report|latency|timehist}
+
+DESCRIPTION
+-----------
+There are several variants of 'perf kwork':
+
+ 'perf kwork record <command>' to record the kernel work
+ of an arbitrary workload.
+
+ 'perf kwork report' to report the per kwork runtime.
+
+ 'perf kwork latency' to report the per kwork latencies.
+
+ 'perf kwork timehist' provides an analysis of kernel work events.
+
+ Example usage:
+ perf kwork record -- sleep 1
+ perf kwork report
+ perf kwork report -b
+ perf kwork latency
+ perf kwork latency -b
+ perf kwork timehist
+
+ By default it shows the individual work events such as irq, workqeueu,
+ including the run time and delay (time between raise and actually entry):
+
+ Runtime start Runtime end Cpu Kwork name Runtime Delaytime
+ (TYPE)NAME:NUM (msec) (msec)
+ ----------------- ----------------- ------ ------------------------- ---------- ----------
+ 1811186.976062 1811186.976327 [0000] (s)RCU:9 0.266 0.114
+ 1811186.978452 1811186.978547 [0000] (s)SCHED:7 0.095 0.171
+ 1811186.980327 1811186.980490 [0000] (s)SCHED:7 0.162 0.083
+ 1811186.981221 1811186.981271 [0000] (s)SCHED:7 0.050 0.077
+ 1811186.984267 1811186.984318 [0000] (s)SCHED:7 0.051 0.075
+ 1811186.987252 1811186.987315 [0000] (s)SCHED:7 0.063 0.081
+ 1811186.987785 1811186.987843 [0006] (s)RCU:9 0.058 0.645
+ 1811186.988319 1811186.988383 [0000] (s)SCHED:7 0.064 0.143
+ 1811186.989404 1811186.989607 [0002] (s)TIMER:1 0.203 0.111
+ 1811186.989660 1811186.989732 [0002] (s)SCHED:7 0.072 0.310
+ 1811186.991295 1811186.991407 [0002] eth0:10 0.112
+ 1811186.991639 1811186.991734 [0002] (s)NET_RX:3 0.095 0.277
+ 1811186.989860 1811186.991826 [0002] (w)vmstat_shepherd 1.966 0.345
+ ...
+
+ Times are in msec.usec.
+
+OPTIONS
+-------
+-D::
+--dump-raw-trace=::
+ Display verbose dump of the sched data.
+
+-f::
+--force::
+ Don't complain, do it.
+
+-k::
+--kwork::
+ List of kwork to profile (irq, softirq, workqueue, etc)
+
+-v::
+--verbose::
+ Be more verbose. (show symbol address, etc)
+
+OPTIONS for 'perf kwork report'
+----------------------------
+
+-b::
+--use-bpf::
+ Use BPF to measure kwork runtime
+
+-C::
+--cpu::
+ Only show events for the given CPU(s) (comma separated list).
+
+-i::
+--input::
+ Input file name. (default: perf.data unless stdin is a fifo)
+
+-n::
+--name::
+ Only show events for the given name.
+
+-s::
+--sort::
+ Sort by key(s): runtime, max, count
+
+-S::
+--with-summary::
+ Show summary with statistics
+
+--time::
+ Only analyze samples within given time window: <start>,<stop>. Times
+ have the format seconds.microseconds. If start is not given (i.e., time
+ string is ',x.y') then analysis starts at the beginning of the file. If
+ stop time is not given (i.e, time string is 'x.y,') then analysis goes
+ to end of file.
+
+OPTIONS for 'perf kwork latency'
+----------------------------
+
+-b::
+--use-bpf::
+ Use BPF to measure kwork latency
+
+-C::
+--cpu::
+ Only show events for the given CPU(s) (comma separated list).
+
+-i::
+--input::
+ Input file name. (default: perf.data unless stdin is a fifo)
+
+-n::
+--name::
+ Only show events for the given name.
+
+-s::
+--sort::
+ Sort by key(s): avg, max, count
+
+--time::
+ Only analyze samples within given time window: <start>,<stop>. Times
+ have the format seconds.microseconds. If start is not given (i.e., time
+ string is ',x.y') then analysis starts at the beginning of the file. If
+ stop time is not given (i.e, time string is 'x.y,') then analysis goes
+ to end of file.
+
+OPTIONS for 'perf kwork timehist'
+---------------------------------
+
+-C::
+--cpu::
+ Only show events for the given CPU(s) (comma separated list).
+
+-g::
+--call-graph::
+ Display call chains if present (default off).
+
+-i::
+--input::
+ Input file name. (default: perf.data unless stdin is a fifo)
+
+-k::
+--vmlinux=<file>::
+ Vmlinux pathname
+
+-n::
+--name::
+ Only show events for the given name.
+
+--kallsyms=<file>::
+ Kallsyms pathname
+
+--max-stack::
+ Maximum number of functions to display in backtrace, default 5.
+
+--symfs=<directory>::
+ Look for files with symbols relative to this directory.
+
+--time::
+ Only analyze samples within given time window: <start>,<stop>. Times
+ have the format seconds.microseconds. If start is not given (i.e., time
+ string is ',x.y') then analysis starts at the beginning of the file. If
+ stop time is not given (i.e, time string is 'x.y,') then analysis goes
+ to end of file.
+
+SEE ALSO
+--------
+linkperf:perf-record[1]