Adding upstream version 5.10.209.upstream/5.10.209

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 497 insertions, 0 deletions

diff --git a/tools/perf/Documentation/perf-stat.txt b/tools/perf/Documentation/perf-stat.txt
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+perf-stat(1)
+============
+
+NAME
+----
+perf-stat - Run a command and gather performance counter statistics
+
+SYNOPSIS
+--------
+[verse]
+'perf stat' [-e <EVENT> | --event=EVENT] [-a] <command>
+'perf stat' [-e <EVENT> | --event=EVENT] [-a] -- <command> [<options>]
+'perf stat' [-e <EVENT> | --event=EVENT] [-a] record [-o file] -- <command> [<options>]
+'perf stat' report [-i file]
+
+DESCRIPTION
+-----------
+This command runs a command and gathers performance counter statistics
+from it.
+
+
+OPTIONS
+-------
+<command>...::
+	Any command you can specify in a shell.
+
+record::
+	See STAT RECORD.
+
+report::
+	See STAT REPORT.
+
+-e::
+--event=::
+	Select the PMU event. Selection can be:
+
+	- a symbolic event name (use 'perf list' to list all events)
+
+	- a raw PMU event (eventsel+umask) in the form of rNNN where NNN is a
+	  hexadecimal event descriptor.
+
+        - a symbolic or raw PMU event followed by an optional colon
+	  and a list of event modifiers, e.g., cpu-cycles:p.  See the
+	  linkperf:perf-list[1] man page for details on event modifiers.
+
+	- a symbolically formed event like 'pmu/param1=0x3,param2/' where
+	  param1 and param2 are defined as formats for the PMU in
+	  /sys/bus/event_source/devices/<pmu>/format/*
+
+	  'percore' is a event qualifier that sums up the event counts for both
+	  hardware threads in a core. For example:
+	  perf stat -A -a -e cpu/event,percore=1/,otherevent ...
+
+	- a symbolically formed event like 'pmu/config=M,config1=N,config2=K/'
+	  where M, N, K are numbers (in decimal, hex, octal format).
+	  Acceptable values for each of 'config', 'config1' and 'config2'
+	  parameters are defined by corresponding entries in
+	  /sys/bus/event_source/devices/<pmu>/format/*
+
+	Note that the last two syntaxes support prefix and glob matching in
+	the PMU name to simplify creation of events across multiple instances
+	of the same type of PMU in large systems (e.g. memory controller PMUs).
+	Multiple PMU instances are typical for uncore PMUs, so the prefix
+	'uncore_' is also ignored when performing this match.
+
+
+-i::
+--no-inherit::
+        child tasks do not inherit counters
+-p::
+--pid=<pid>::
+        stat events on existing process id (comma separated list)
+
+-t::
+--tid=<tid>::
+        stat events on existing thread id (comma separated list)
+
+ifdef::HAVE_LIBPFM[]
+--pfm-events events::
+Select a PMU event using libpfm4 syntax (see http://perfmon2.sf.net)
+including support for event filters. For example '--pfm-events
+inst_retired:any_p:u:c=1:i'. More than one event can be passed to the
+option using the comma separator. Hardware events and generic hardware
+events cannot be mixed together. The latter must be used with the -e
+option. The -e option and this one can be mixed and matched.  Events
+can be grouped using the {} notation.
+endif::HAVE_LIBPFM[]
+
+-a::
+--all-cpus::
+        system-wide collection from all CPUs (default if no target is specified)
+
+--no-scale::
+	Don't scale/normalize counter values
+
+-d::
+--detailed::
+	print more detailed statistics, can be specified up to 3 times
+
+	   -d:          detailed events, L1 and LLC data cache
+        -d -d:     more detailed events, dTLB and iTLB events
+     -d -d -d:     very detailed events, adding prefetch events
+
+-r::
+--repeat=<n>::
+	repeat command and print average + stddev (max: 100). 0 means forever.
+
+-B::
+--big-num::
+        print large numbers with thousands' separators according to locale.
+	Enabled by default. Use "--no-big-num" to disable.
+	Default setting can be changed with "perf config stat.big-num=false".
+
+-C::
+--cpu=::
+Count 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.
+In per-thread mode, this option is ignored. The -a option is still necessary
+to activate system-wide monitoring. Default is to count on all CPUs.
+
+-A::
+--no-aggr::
+Do not aggregate counts across all monitored CPUs.
+
+-n::
+--null::
+        null run - don't start any counters
+
+-v::
+--verbose::
+        be more verbose (show counter open errors, etc)
+
+-x SEP::
+--field-separator SEP::
+print counts using a CSV-style output to make it easy to import directly into
+spreadsheets. Columns are separated by the string specified in SEP.
+
+--table:: Display time for each run (-r option), in a table format, e.g.:
+
+  $ perf stat --null -r 5 --table perf bench sched pipe
+
+   Performance counter stats for 'perf bench sched pipe' (5 runs):
+
+             # Table of individual measurements:
+             5.189 (-0.293) #
+             5.189 (-0.294) #
+             5.186 (-0.296) #
+             5.663 (+0.181) ##
+             6.186 (+0.703) ####
+
+             # Final result:
+             5.483 +- 0.198 seconds time elapsed  ( +-  3.62% )
+
+-G name::
+--cgroup name::
+monitor only in the container (cgroup) called "name". This option is available only
+in per-cpu mode. The cgroup filesystem must be mounted. All threads belonging to
+container "name" are monitored when they run on the monitored CPUs. Multiple cgroups
+can be provided. Each cgroup is applied to the corresponding event, i.e., first cgroup
+to first event, second cgroup to second event and so on. It is possible to provide
+an empty cgroup (monitor all the time) using, e.g., -G foo,,bar. Cgroups must have
+corresponding events, i.e., they always refer to events defined earlier on the command
+line. If the user wants to track multiple events for a specific cgroup, the user can
+use '-e e1 -e e2 -G foo,foo' or just use '-e e1 -e e2 -G foo'.
+
+If wanting to monitor, say, 'cycles' for a cgroup and also for system wide, this
+command line can be used: 'perf stat -e cycles -G cgroup_name -a -e cycles'.
+
+--for-each-cgroup name::
+Expand event list for each cgroup in "name" (allow multiple cgroups separated
+by comma).  This has same effect that repeating -e option and -G option for
+each event x name.  This option cannot be used with -G/--cgroup option.
+
+-o file::
+--output file::
+Print the output into the designated file.
+
+--append::
+Append to the output file designated with the -o option. Ignored if -o is not specified.
+
+--log-fd::
+
+Log output to fd, instead of stderr.  Complementary to --output, and mutually exclusive
+with it.  --append may be used here.  Examples:
+     3>results  perf stat --log-fd 3          -- $cmd
+     3>>results perf stat --log-fd 3 --append -- $cmd
+
+--control=fifo:ctl-fifo[,ack-fifo]::
+--control=fd:ctl-fd[,ack-fd]::
+ctl-fifo / ack-fifo are opened and used as ctl-fd / ack-fd as follows.
+Listen on ctl-fd descriptor for command to control measurement ('enable': enable events,
+'disable': disable events). Measurements can be started with events disabled using
+--delay=-1 option. Optionally send control command completion ('ack\n') to ack-fd descriptor
+to synchronize with the controlling process. Example of bash shell script to enable and
+disable events during measurements:
+
+ #!/bin/bash
+
+ ctl_dir=/tmp/
+
+ ctl_fifo=${ctl_dir}perf_ctl.fifo
+ test -p ${ctl_fifo} && unlink ${ctl_fifo}
+ mkfifo ${ctl_fifo}
+ exec {ctl_fd}<>${ctl_fifo}
+
+ ctl_ack_fifo=${ctl_dir}perf_ctl_ack.fifo
+ test -p ${ctl_ack_fifo} && unlink ${ctl_ack_fifo}
+ mkfifo ${ctl_ack_fifo}
+ exec {ctl_fd_ack}<>${ctl_ack_fifo}
+
+ perf stat -D -1 -e cpu-cycles -a -I 1000       \
+           --control fd:${ctl_fd},${ctl_fd_ack} \
+           -- sleep 30 &
+ perf_pid=$!
+
+ sleep 5  && echo 'enable' >&${ctl_fd} && read -u ${ctl_fd_ack} e1 && echo "enabled(${e1})"
+ sleep 10 && echo 'disable' >&${ctl_fd} && read -u ${ctl_fd_ack} d1 && echo "disabled(${d1})"
+
+ exec {ctl_fd_ack}>&-
+ unlink ${ctl_ack_fifo}
+
+ exec {ctl_fd}>&-
+ unlink ${ctl_fifo}
+
+ wait -n ${perf_pid}
+ exit $?
+
+
+--pre::
+--post::
+	Pre and post measurement hooks, e.g.:
+
+perf stat --repeat 10 --null --sync --pre 'make -s O=defconfig-build/clean' -- make -s -j64 O=defconfig-build/ bzImage
+
+-I msecs::
+--interval-print msecs::
+Print count deltas every N milliseconds (minimum: 1ms)
+The overhead percentage could be high in some cases, for instance with small, sub 100ms intervals.  Use with caution.
+	example: 'perf stat -I 1000 -e cycles -a sleep 5'
+
+If the metric exists, it is calculated by the counts generated in this interval and the metric is printed after #.
+
+--interval-count times::
+Print count deltas for fixed number of times.
+This option should be used together with "-I" option.
+	example: 'perf stat -I 1000 --interval-count 2 -e cycles -a'
+
+--interval-clear::
+Clear the screen before next interval.
+
+--timeout msecs::
+Stop the 'perf stat' session and print count deltas after N milliseconds (minimum: 10 ms).
+This option is not supported with the "-I" option.
+	example: 'perf stat --time 2000 -e cycles -a'
+
+--metric-only::
+Only print computed metrics. Print them in a single line.
+Don't show any raw values. Not supported with --per-thread.
+
+--per-socket::
+Aggregate counts per processor socket for system-wide mode measurements.  This
+is a useful mode to detect imbalance between sockets.  To enable this mode,
+use --per-socket in addition to -a. (system-wide).  The output includes the
+socket number and the number of online processors on that socket. This is
+useful to gauge the amount of aggregation.
+
+--per-die::
+Aggregate counts per processor die for system-wide mode measurements.  This
+is a useful mode to detect imbalance between dies.  To enable this mode,
+use --per-die in addition to -a. (system-wide).  The output includes the
+die number and the number of online processors on that die. This is
+useful to gauge the amount of aggregation.
+
+--per-core::
+Aggregate counts per physical processor for system-wide mode measurements.  This
+is a useful mode to detect imbalance between physical cores.  To enable this mode,
+use --per-core in addition to -a. (system-wide).  The output includes the
+core number and the number of online logical processors on that physical processor.
+
+--per-thread::
+Aggregate counts per monitored threads, when monitoring threads (-t option)
+or processes (-p option).
+
+--per-node::
+Aggregate counts per NUMA nodes for system-wide mode measurements. This
+is a useful mode to detect imbalance between NUMA nodes. To enable this
+mode, use --per-node in addition to -a. (system-wide).
+
+-D msecs::
+--delay msecs::
+After starting the program, wait msecs before measuring (-1: start with events
+disabled). This is useful to filter out the startup phase of the program,
+which is often very different.
+
+-T::
+--transaction::
+
+Print statistics of transactional execution if supported.
+
+--metric-no-group::
+By default, events to compute a metric are placed in weak groups. The
+group tries to enforce scheduling all or none of the events. The
+--metric-no-group option places events outside of groups and may
+increase the chance of the event being scheduled - leading to more
+accuracy. However, as events may not be scheduled together accuracy
+for metrics like instructions per cycle can be lower - as both metrics
+may no longer be being measured at the same time.
+
+--metric-no-merge::
+By default metric events in different weak groups can be shared if one
+group contains all the events needed by another. In such cases one
+group will be eliminated reducing event multiplexing and making it so
+that certain groups of metrics sum to 100%. A downside to sharing a
+group is that the group may require multiplexing and so accuracy for a
+small group that need not have multiplexing is lowered. This option
+forbids the event merging logic from sharing events between groups and
+may be used to increase accuracy in this case.
+
+STAT RECORD
+-----------
+Stores stat data into perf data file.
+
+-o file::
+--output file::
+Output file name.
+
+STAT REPORT
+-----------
+Reads and reports stat data from perf data file.
+
+-i file::
+--input file::
+Input file name.
+
+--per-socket::
+Aggregate counts per processor socket for system-wide mode measurements.
+
+--per-die::
+Aggregate counts per processor die for system-wide mode measurements.
+
+--per-core::
+Aggregate counts per physical processor for system-wide mode measurements.
+
+-M::
+--metrics::
+Print metrics or metricgroups specified in a comma separated list.
+For a group all metrics from the group are added.
+The events from the metrics are automatically measured.
+See perf list output for the possble metrics and metricgroups.
+
+-A::
+--no-aggr::
+Do not aggregate counts across all monitored CPUs.
+
+--topdown::
+Print top down level 1 metrics if supported by the CPU. This allows to
+determine bottle necks in the CPU pipeline for CPU bound workloads,
+by breaking the cycles consumed down into frontend bound, backend bound,
+bad speculation and retiring.
+
+Frontend bound means that the CPU cannot fetch and decode instructions fast
+enough. Backend bound means that computation or memory access is the bottle
+neck. Bad Speculation means that the CPU wasted cycles due to branch
+mispredictions and similar issues. Retiring means that the CPU computed without
+an apparently bottleneck. The bottleneck is only the real bottleneck
+if the workload is actually bound by the CPU and not by something else.
+
+For best results it is usually a good idea to use it with interval
+mode like -I 1000, as the bottleneck of workloads can change often.
+
+This enables --metric-only, unless overridden with --no-metric-only.
+
+The following restrictions only apply to older Intel CPUs and Atom,
+on newer CPUs (IceLake and later) TopDown can be collected for any thread:
+
+The top down metrics are collected per core instead of per
+CPU thread. Per core mode is automatically enabled
+and -a (global monitoring) is needed, requiring root rights or
+perf.perf_event_paranoid=-1.
+
+Topdown uses the full Performance Monitoring Unit, and needs
+disabling of the NMI watchdog (as root):
+echo 0 > /proc/sys/kernel/nmi_watchdog
+for best results. Otherwise the bottlenecks may be inconsistent
+on workload with changing phases.
+
+To interpret the results it is usually needed to know on which
+CPUs the workload runs on. If needed the CPUs can be forced using
+taskset.
+
+--no-merge::
+Do not merge results from same PMUs.
+
+When multiple events are created from a single event specification,
+stat will, by default, aggregate the event counts and show the result
+in a single row. This option disables that behavior and shows
+the individual events and counts.
+
+Multiple events are created from a single event specification when:
+1. Prefix or glob matching is used for the PMU name.
+2. Aliases, which are listed immediately after the Kernel PMU events
+   by perf list, are used.
+
+--smi-cost::
+Measure SMI cost if msr/aperf/ and msr/smi/ events are supported.
+
+During the measurement, the /sys/device/cpu/freeze_on_smi will be set to
+freeze core counters on SMI.
+The aperf counter will not be effected by the setting.
+The cost of SMI can be measured by (aperf - unhalted core cycles).
+
+In practice, the percentages of SMI cycles is very useful for performance
+oriented analysis. --metric_only will be applied by default.
+The output is SMI cycles%, equals to (aperf - unhalted core cycles) / aperf
+
+Users who wants to get the actual value can apply --no-metric-only.
+
+--all-kernel::
+Configure all used events to run in kernel space.
+
+--all-user::
+Configure all used events to run in user space.
+
+--percore-show-thread::
+The event modifier "percore" has supported to sum up the event counts
+for all hardware threads in a core and show the counts per core.
+
+This option with event modifier "percore" enabled also sums up the event
+counts for all hardware threads in a core but show the sum counts per
+hardware thread. This is essentially a replacement for the any bit and
+convenient for post processing.
+
+--summary::
+Print summary for interval mode (-I).
+
+EXAMPLES
+--------
+
+$ perf stat -- make
+
+   Performance counter stats for 'make':
+
+        83723.452481      task-clock:u (msec)       #    1.004 CPUs utilized
+                   0      context-switches:u        #    0.000 K/sec
+                   0      cpu-migrations:u          #    0.000 K/sec
+           3,228,188      page-faults:u             #    0.039 M/sec
+     229,570,665,834      cycles:u                  #    2.742 GHz
+     313,163,853,778      instructions:u            #    1.36  insn per cycle
+      69,704,684,856      branches:u                #  832.559 M/sec
+       2,078,861,393      branch-misses:u           #    2.98% of all branches
+
+        83.409183620 seconds time elapsed
+
+        74.684747000 seconds user
+         8.739217000 seconds sys
+
+TIMINGS
+-------
+As displayed in the example above we can display 3 types of timings.
+We always display the time the counters were enabled/alive:
+
+        83.409183620 seconds time elapsed
+
+For workload sessions we also display time the workloads spent in
+user/system lands:
+
+        74.684747000 seconds user
+         8.739217000 seconds sys
+
+Those times are the very same as displayed by the 'time' tool.
+
+CSV FORMAT
+----------
+
+With -x, perf stat is able to output a not-quite-CSV format output
+Commas in the output are not put into "". To make it easy to parse
+it is recommended to use a different character like -x \;
+
+The fields are in this order:
+
+	- optional usec time stamp in fractions of second (with -I xxx)
+	- optional CPU, core, or socket identifier
+	- optional number of logical CPUs aggregated
+	- counter value
+	- unit of the counter value or empty
+	- event name
+	- run time of counter
+	- percentage of measurement time the counter was running
+	- optional variance if multiple values are collected with -r
+	- optional metric value
+	- optional unit of metric
+
+Additional metrics may be printed with all earlier fields being empty.
+
+SEE ALSO
+--------
+linkperf:perf-top[1], linkperf:perf-list[1]