summaryrefslogtreecommitdiffstats
path: root/Documentation/tools/rtla
diff options
context:
space:
mode:
Diffstat (limited to 'Documentation/tools/rtla')
-rw-r--r--Documentation/tools/rtla/Makefile53
-rw-r--r--Documentation/tools/rtla/common_appendix.rst13
-rw-r--r--Documentation/tools/rtla/common_hist_options.rst23
-rw-r--r--Documentation/tools/rtla/common_options.rst47
-rw-r--r--Documentation/tools/rtla/common_osnoise_description.rst8
-rw-r--r--Documentation/tools/rtla/common_osnoise_options.rst27
-rw-r--r--Documentation/tools/rtla/common_timerlat_description.rst10
-rw-r--r--Documentation/tools/rtla/common_timerlat_options.rst28
-rw-r--r--Documentation/tools/rtla/common_top_options.rst3
-rw-r--r--Documentation/tools/rtla/index.rst26
-rw-r--r--Documentation/tools/rtla/rtla-osnoise-hist.rst66
-rw-r--r--Documentation/tools/rtla/rtla-osnoise-top.rst61
-rw-r--r--Documentation/tools/rtla/rtla-osnoise.rst59
-rw-r--r--Documentation/tools/rtla/rtla-timerlat-hist.rst106
-rw-r--r--Documentation/tools/rtla/rtla-timerlat-top.rst145
-rw-r--r--Documentation/tools/rtla/rtla-timerlat.rst57
-rw-r--r--Documentation/tools/rtla/rtla.rst48
17 files changed, 780 insertions, 0 deletions
diff --git a/Documentation/tools/rtla/Makefile b/Documentation/tools/rtla/Makefile
new file mode 100644
index 000000000..093af6d7a
--- /dev/null
+++ b/Documentation/tools/rtla/Makefile
@@ -0,0 +1,53 @@
+# SPDX-License-Identifier: GPL-2.0-only
+# Based on bpftool's Documentation Makefile
+
+INSTALL ?= install
+RM ?= rm -f
+RMDIR ?= rmdir --ignore-fail-on-non-empty
+
+PREFIX ?= /usr/share
+MANDIR ?= $(PREFIX)/man
+MAN1DIR = $(MANDIR)/man1
+
+MAN1_RST = $(wildcard rtla*.rst)
+
+_DOC_MAN1 = $(patsubst %.rst,%.1,$(MAN1_RST))
+DOC_MAN1 = $(addprefix $(OUTPUT),$(_DOC_MAN1))
+
+RST2MAN_DEP := $(shell command -v rst2man 2>/dev/null)
+RST2MAN_OPTS += --verbose
+
+TEST_RST2MAN = $(shell sh -c "rst2man --version > /dev/null 2>&1 || echo n")
+
+$(OUTPUT)%.1: %.rst
+ifndef RST2MAN_DEP
+ $(info ********************************************)
+ $(info ** NOTICE: rst2man not found)
+ $(info **)
+ $(info ** Consider installing the latest rst2man from your)
+ $(info ** distribution, e.g., 'dnf install python3-docutils' on Fedora,)
+ $(info ** or from source:)
+ $(info **)
+ $(info ** https://docutils.sourceforge.io/docs/dev/repository.html )
+ $(info **)
+ $(info ********************************************)
+ $(error NOTICE: rst2man required to generate man pages)
+endif
+ rst2man $(RST2MAN_OPTS) $< > $@
+
+man1: $(DOC_MAN1)
+man: man1
+
+clean:
+ $(RM) $(DOC_MAN1)
+
+install: man
+ $(INSTALL) -d -m 755 $(DESTDIR)$(MAN1DIR)
+ $(INSTALL) -m 644 $(DOC_MAN1) $(DESTDIR)$(MAN1DIR)
+
+uninstall:
+ $(RM) $(addprefix $(DESTDIR)$(MAN1DIR)/,$(_DOC_MAN1))
+ $(RMDIR) $(DESTDIR)$(MAN1DIR)
+
+.PHONY: man man1 clean install uninstall
+.DEFAULT_GOAL := man
diff --git a/Documentation/tools/rtla/common_appendix.rst b/Documentation/tools/rtla/common_appendix.rst
new file mode 100644
index 000000000..b5cf2dc22
--- /dev/null
+++ b/Documentation/tools/rtla/common_appendix.rst
@@ -0,0 +1,13 @@
+REPORTING BUGS
+==============
+Report bugs to <linux-kernel@vger.kernel.org>
+and <linux-trace-devel@vger.kernel.org>
+
+LICENSE
+=======
+**rtla** is Free Software licensed under the GNU GPLv2
+
+COPYING
+=======
+Copyright \(C) 2021 Red Hat, Inc. Free use of this software is granted under
+the terms of the GNU Public License (GPL).
diff --git a/Documentation/tools/rtla/common_hist_options.rst b/Documentation/tools/rtla/common_hist_options.rst
new file mode 100644
index 000000000..df53ff835
--- /dev/null
+++ b/Documentation/tools/rtla/common_hist_options.rst
@@ -0,0 +1,23 @@
+**-b**, **--bucket-size** *N*
+
+ Set the histogram bucket size (default *1*).
+
+**-E**, **--entries** *N*
+
+ Set the number of entries of the histogram (default 256).
+
+**--no-header**
+
+ Do not print header.
+
+**--no-summary**
+
+ Do not print summary.
+
+**--no-index**
+
+ Do not print index.
+
+**--with-zeros**
+
+ Print zero only entries.
diff --git a/Documentation/tools/rtla/common_options.rst b/Documentation/tools/rtla/common_options.rst
new file mode 100644
index 000000000..af76df620
--- /dev/null
+++ b/Documentation/tools/rtla/common_options.rst
@@ -0,0 +1,47 @@
+**-c**, **--cpus** *cpu-list*
+
+ Set the osnoise tracer to run the sample threads in the cpu-list.
+
+**-d**, **--duration** *time[s|m|h|d]*
+
+ Set the duration of the session.
+
+**-D**, **--debug**
+
+ Print debug info.
+
+**-t**, **--trace**\[*=file*]
+
+ Save the stopped trace to [*file|osnoise_trace.txt*].
+
+**-e**, **--event** *sys:event*
+
+ Enable an event in the trace (**-t**) session. The argument can be a specific event, e.g., **-e** *sched:sched_switch*, or all events of a system group, e.g., **-e** *sched*. Multiple **-e** are allowed. It is only active when **-t** or **-a** are set.
+
+**--filter** *<filter>*
+
+ Filter the previous **-e** *sys:event* event with *<filter>*. For further information about event filtering see https://www.kernel.org/doc/html/latest/trace/events.html#event-filtering.
+
+**--trigger** *<trigger>*
+ Enable a trace event trigger to the previous **-e** *sys:event*.
+ If the *hist:* trigger is activated, the output histogram will be automatically saved to a file named *system_event_hist.txt*.
+ For example, the command:
+
+ rtla <command> <mode> -t -e osnoise:irq_noise --trigger="hist:key=desc,duration/1000:sort=desc,duration/1000:vals=hitcount"
+
+ Will automatically save the content of the histogram associated to *osnoise:irq_noise* event in *osnoise_irq_noise_hist.txt*.
+
+ For further information about event trigger see https://www.kernel.org/doc/html/latest/trace/events.html#event-triggers.
+
+**-P**, **--priority** *o:prio|r:prio|f:prio|d:runtime:period*
+
+ Set scheduling parameters to the osnoise tracer threads, the format to set the priority are:
+
+ - *o:prio* - use SCHED_OTHER with *prio*;
+ - *r:prio* - use SCHED_RR with *prio*;
+ - *f:prio* - use SCHED_FIFO with *prio*;
+ - *d:runtime[us|ms|s]:period[us|ms|s]* - use SCHED_DEADLINE with *runtime* and *period* in nanoseconds.
+
+**-h**, **--help**
+
+ Print help menu.
diff --git a/Documentation/tools/rtla/common_osnoise_description.rst b/Documentation/tools/rtla/common_osnoise_description.rst
new file mode 100644
index 000000000..d5d61615b
--- /dev/null
+++ b/Documentation/tools/rtla/common_osnoise_description.rst
@@ -0,0 +1,8 @@
+The **rtla osnoise** tool is an interface for the *osnoise* tracer. The
+*osnoise* tracer dispatches a kernel thread per-cpu. These threads read the
+time in a loop while with preemption, softirq and IRQs enabled, thus
+allowing all the sources of operating system noise during its execution.
+The *osnoise*'s tracer threads take note of the delta between each time
+read, along with an interference counter of all sources of interference.
+At the end of each period, the *osnoise* tracer displays a summary of
+the results.
diff --git a/Documentation/tools/rtla/common_osnoise_options.rst b/Documentation/tools/rtla/common_osnoise_options.rst
new file mode 100644
index 000000000..f792ca58c
--- /dev/null
+++ b/Documentation/tools/rtla/common_osnoise_options.rst
@@ -0,0 +1,27 @@
+**-a**, **--auto** *us*
+
+ Set the automatic trace mode. This mode sets some commonly used options
+ while debugging the system. It is equivalent to use **-s** *us* **-T 1 -t**.
+
+**-p**, **--period** *us*
+
+ Set the *osnoise* tracer period in microseconds.
+
+**-r**, **--runtime** *us*
+
+ Set the *osnoise* tracer runtime in microseconds.
+
+**-s**, **--stop** *us*
+
+ Stop the trace if a single sample is higher than the argument in microseconds.
+ If **-T** is set, it will also save the trace to the output.
+
+**-S**, **--stop-total** *us*
+
+ Stop the trace if the total sample is higher than the argument in microseconds.
+ If **-T** is set, it will also save the trace to the output.
+
+**-T**, **--threshold** *us*
+
+ Specify the minimum delta between two time reads to be considered noise.
+ The default threshold is *5 us*.
diff --git a/Documentation/tools/rtla/common_timerlat_description.rst b/Documentation/tools/rtla/common_timerlat_description.rst
new file mode 100644
index 000000000..321201cb8
--- /dev/null
+++ b/Documentation/tools/rtla/common_timerlat_description.rst
@@ -0,0 +1,10 @@
+The **rtla timerlat** tool is an interface for the *timerlat* tracer. The
+*timerlat* tracer dispatches a kernel thread per-cpu. These threads
+set a periodic timer to wake themselves up and go back to sleep. After
+the wakeup, they collect and generate useful information for the
+debugging of operating system timer latency.
+
+The *timerlat* tracer outputs information in two ways. It periodically
+prints the timer latency at the timer *IRQ* handler and the *Thread*
+handler. It also enable the trace of the most relevant information via
+**osnoise:** tracepoints.
diff --git a/Documentation/tools/rtla/common_timerlat_options.rst b/Documentation/tools/rtla/common_timerlat_options.rst
new file mode 100644
index 000000000..bacdea6de
--- /dev/null
+++ b/Documentation/tools/rtla/common_timerlat_options.rst
@@ -0,0 +1,28 @@
+**-a**, **--auto** *us*
+
+ Set the automatic trace mode. This mode sets some commonly used options
+ while debugging the system. It is equivalent to use **-T** *us* **-s** *us*
+ **-t**. By default, *timerlat* tracer uses FIFO:95 for *timerlat* threads,
+ thus equilavent to **-P** *f:95*.
+
+**-p**, **--period** *us*
+
+ Set the *timerlat* tracer period in microseconds.
+
+**-i**, **--irq** *us*
+
+ Stop trace if the *IRQ* latency is higher than the argument in us.
+
+**-T**, **--thread** *us*
+
+ Stop trace if the *Thread* latency is higher than the argument in us.
+
+**-s**, **--stack** *us*
+
+ Save the stack trace at the *IRQ* if a *Thread* latency is higher than the
+ argument in us.
+
+**--dma-latency** *us*
+ Set the /dev/cpu_dma_latency to *us*, aiming to bound exit from idle latencies.
+ *cyclictest* sets this value to *0* by default, use **--dma-latency** *0* to have
+ similar results.
diff --git a/Documentation/tools/rtla/common_top_options.rst b/Documentation/tools/rtla/common_top_options.rst
new file mode 100644
index 000000000..f48878938
--- /dev/null
+++ b/Documentation/tools/rtla/common_top_options.rst
@@ -0,0 +1,3 @@
+**-q**, **--quiet**
+
+ Print only a summary at the end of the session.
diff --git a/Documentation/tools/rtla/index.rst b/Documentation/tools/rtla/index.rst
new file mode 100644
index 000000000..840f0bf3e
--- /dev/null
+++ b/Documentation/tools/rtla/index.rst
@@ -0,0 +1,26 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+================================
+The realtime Linux analysis tool
+================================
+
+RTLA provides a set of tools for the analysis of the kernel's realtime
+behavior on specific hardware.
+
+.. toctree::
+ :maxdepth: 1
+
+ rtla
+ rtla-osnoise
+ rtla-osnoise-hist
+ rtla-osnoise-top
+ rtla-timerlat
+ rtla-timerlat-hist
+ rtla-timerlat-top
+
+.. only:: subproject and html
+
+ Indices
+ =======
+
+ * :ref:`genindex`
diff --git a/Documentation/tools/rtla/rtla-osnoise-hist.rst b/Documentation/tools/rtla/rtla-osnoise-hist.rst
new file mode 100644
index 000000000..f2e79d22c
--- /dev/null
+++ b/Documentation/tools/rtla/rtla-osnoise-hist.rst
@@ -0,0 +1,66 @@
+===================
+rtla-osnoise-hist
+===================
+------------------------------------------------------
+Display a histogram of the osnoise tracer samples
+------------------------------------------------------
+
+:Manual section: 1
+
+SYNOPSIS
+========
+**rtla osnoise hist** [*OPTIONS*]
+
+DESCRIPTION
+===========
+.. include:: common_osnoise_description.rst
+
+The **rtla osnoise hist** tool collects all **osnoise:sample_threshold**
+occurrence in a histogram, displaying the results in a user-friendly way.
+The tool also allows many configurations of the *osnoise* tracer and the
+collection of the tracer output.
+
+OPTIONS
+=======
+.. include:: common_osnoise_options.rst
+
+.. include:: common_hist_options.rst
+
+.. include:: common_options.rst
+
+EXAMPLE
+=======
+In the example below, *osnoise* tracer threads are set to run with real-time
+priority *FIFO:1*, on CPUs *0-11*, for *900ms* at each period (*1s* by
+default). The reason for reducing the runtime is to avoid starving the
+**rtla** tool. The tool is also set to run for *one minute*. The output
+histogram is set to group outputs in buckets of *10us* and *25* entries::
+
+ [root@f34 ~/]# rtla osnoise hist -P F:1 -c 0-11 -r 900000 -d 1M -b 10 -E 25
+ # RTLA osnoise histogram
+ # Time unit is microseconds (us)
+ # Duration: 0 00:01:00
+ Index CPU-000 CPU-001 CPU-002 CPU-003 CPU-004 CPU-005 CPU-006 CPU-007 CPU-008 CPU-009 CPU-010 CPU-011
+ 0 42982 46287 51779 53740 52024 44817 49898 36500 50408 50128 49523 52377
+ 10 12224 8356 2912 878 2667 10155 4573 18894 4214 4836 5708 2413
+ 20 8 5 12 2 13 24 20 41 29 53 39 39
+ 30 1 1 0 0 10 3 6 19 15 31 30 38
+ 40 0 0 0 0 0 4 2 7 2 3 8 11
+ 50 0 0 0 0 0 0 0 0 0 1 1 2
+ over: 0 0 0 0 0 0 0 0 0 0 0 0
+ count: 55215 54649 54703 54620 54714 55003 54499 55461 54668 55052 55309 54880
+ min: 0 0 0 0 0 0 0 0 0 0 0 0
+ avg: 0 0 0 0 0 0 0 0 0 0 0 0
+ max: 30 30 20 20 30 40 40 40 40 50 50 50
+
+SEE ALSO
+========
+**rtla-osnoise**\(1), **rtla-osnoise-top**\(1)
+
+*osnoise* tracer documentation: <https://www.kernel.org/doc/html/latest/trace/osnoise-tracer.html>
+
+AUTHOR
+======
+Written by Daniel Bristot de Oliveira <bristot@kernel.org>
+
+.. include:: common_appendix.rst
diff --git a/Documentation/tools/rtla/rtla-osnoise-top.rst b/Documentation/tools/rtla/rtla-osnoise-top.rst
new file mode 100644
index 000000000..5d75d1394
--- /dev/null
+++ b/Documentation/tools/rtla/rtla-osnoise-top.rst
@@ -0,0 +1,61 @@
+===================
+rtla-osnoise-top
+===================
+-----------------------------------------------
+Display a summary of the operating system noise
+-----------------------------------------------
+
+:Manual section: 1
+
+SYNOPSIS
+========
+**rtla osnoise top** [*OPTIONS*]
+
+DESCRIPTION
+===========
+.. include:: common_osnoise_description.rst
+
+**rtla osnoise top** collects the periodic summary from the *osnoise* tracer,
+including the counters of the occurrence of the interference source,
+displaying the results in a user-friendly format.
+
+The tool also allows many configurations of the *osnoise* tracer and the
+collection of the tracer output.
+
+OPTIONS
+=======
+.. include:: common_osnoise_options.rst
+
+.. include:: common_top_options.rst
+
+.. include:: common_options.rst
+
+EXAMPLE
+=======
+In the example below, the **rtla osnoise top** tool is set to run with a
+real-time priority *FIFO:1*, on CPUs *0-3*, for *900ms* at each period
+(*1s* by default). The reason for reducing the runtime is to avoid starving
+the rtla tool. The tool is also set to run for *one minute* and to display
+a summary of the report at the end of the session::
+
+ [root@f34 ~]# rtla osnoise top -P F:1 -c 0-3 -r 900000 -d 1M -q
+ Operating System Noise
+ duration: 0 00:01:00 | time is in us
+ CPU Period Runtime Noise % CPU Aval Max Noise Max Single HW NMI IRQ Softirq Thread
+ 0 #59 53100000 304896 99.42580 6978 56 549 0 53111 1590 13
+ 1 #59 53100000 338339 99.36282 8092 24 399 0 53130 1448 31
+ 2 #59 53100000 290842 99.45227 6582 39 855 0 53110 1406 12
+ 3 #59 53100000 204935 99.61405 6251 33 290 0 53156 1460 12
+
+SEE ALSO
+========
+
+**rtla-osnoise**\(1), **rtla-osnoise-hist**\(1)
+
+Osnoise tracer documentation: <https://www.kernel.org/doc/html/latest/trace/osnoise-tracer.html>
+
+AUTHOR
+======
+Written by Daniel Bristot de Oliveira <bristot@kernel.org>
+
+.. include:: common_appendix.rst
diff --git a/Documentation/tools/rtla/rtla-osnoise.rst b/Documentation/tools/rtla/rtla-osnoise.rst
new file mode 100644
index 000000000..c129b206c
--- /dev/null
+++ b/Documentation/tools/rtla/rtla-osnoise.rst
@@ -0,0 +1,59 @@
+===============
+rtla-osnoise
+===============
+------------------------------------------------------------------
+Measure the operating system noise
+------------------------------------------------------------------
+
+:Manual section: 1
+
+SYNOPSIS
+========
+**rtla osnoise** [*MODE*] ...
+
+DESCRIPTION
+===========
+
+.. include:: common_osnoise_description.rst
+
+The *osnoise* tracer outputs information in two ways. It periodically prints
+a summary of the noise of the operating system, including the counters of
+the occurrence of the source of interference. It also provides information
+for each noise via the **osnoise:** tracepoints. The **rtla osnoise top**
+mode displays information about the periodic summary from the *osnoise* tracer.
+The **rtla osnoise hist** mode displays information about the noise using
+the **osnoise:** tracepoints. For further details, please refer to the
+respective man page.
+
+MODES
+=====
+**top**
+
+ Prints the summary from osnoise tracer.
+
+**hist**
+
+ Prints a histogram of osnoise samples.
+
+If no MODE is given, the top mode is called, passing the arguments.
+
+OPTIONS
+=======
+
+**-h**, **--help**
+
+ Display the help text.
+
+For other options, see the man page for the corresponding mode.
+
+SEE ALSO
+========
+**rtla-osnoise-top**\(1), **rtla-osnoise-hist**\(1)
+
+Osnoise tracer documentation: <https://www.kernel.org/doc/html/latest/trace/osnoise-tracer.html>
+
+AUTHOR
+======
+Written by Daniel Bristot de Oliveira <bristot@kernel.org>
+
+.. include:: common_appendix.rst
diff --git a/Documentation/tools/rtla/rtla-timerlat-hist.rst b/Documentation/tools/rtla/rtla-timerlat-hist.rst
new file mode 100644
index 000000000..6bf7f0ca4
--- /dev/null
+++ b/Documentation/tools/rtla/rtla-timerlat-hist.rst
@@ -0,0 +1,106 @@
+=====================
+rtla-timerlat-hist
+=====================
+------------------------------------------------
+Histograms of the operating system timer latency
+------------------------------------------------
+
+:Manual section: 1
+
+SYNOPSIS
+========
+**rtla timerlat hist** [*OPTIONS*] ...
+
+DESCRIPTION
+===========
+
+.. include:: common_timerlat_description.rst
+
+The **rtla timerlat hist** displays a histogram of each tracer event
+occurrence. This tool uses the periodic information, and the
+**osnoise:** tracepoints are enabled when using the **-T** option.
+
+OPTIONS
+=======
+
+.. include:: common_timerlat_options.rst
+
+.. include:: common_hist_options.rst
+
+.. include:: common_options.rst
+
+EXAMPLE
+=======
+In the example below, **rtla timerlat hist** is set to run for *10* minutes,
+in the cpus *0-4*, *skipping zero* only lines. Moreover, **rtla timerlat
+hist** will change the priority of the *timerlat* threads to run under
+*SCHED_DEADLINE* priority, with a *10us* runtime every *1ms* period. The
+*1ms* period is also passed to the *timerlat* tracer::
+
+ [root@alien ~]# timerlat hist -d 10m -c 0-4 -P d:100us:1ms -p 1ms
+ # RTLA timerlat histogram
+ # Time unit is microseconds (us)
+ # Duration: 0 00:10:00
+ Index IRQ-000 Thr-000 IRQ-001 Thr-001 IRQ-002 Thr-002 IRQ-003 Thr-003 IRQ-004 Thr-004
+ 0 276489 0 206089 0 466018 0 481102 0 205546 0
+ 1 318327 35487 388149 30024 94531 48382 83082 71078 388026 55730
+ 2 3282 122584 4019 126527 28231 109012 23311 89309 4568 98739
+ 3 940 11815 837 9863 6209 16227 6895 17196 910 9780
+ 4 444 17287 424 11574 2097 38443 2169 36736 462 13476
+ 5 206 43291 255 25581 1223 101908 1304 101137 236 28913
+ 6 132 101501 96 64584 635 213774 757 215471 99 73453
+ 7 74 169347 65 124758 350 57466 441 53639 69 148573
+ 8 53 85183 31 156751 229 9052 306 9026 39 139907
+ 9 22 10387 12 42762 161 2554 225 2689 19 26192
+ 10 13 1898 8 5770 114 1247 128 1405 13 3772
+ 11 9 560 9 924 71 686 76 765 8 713
+ 12 4 256 2 360 50 411 64 474 3 278
+ 13 2 167 2 172 43 256 53 350 4 180
+ 14 1 88 1 116 15 198 42 223 0 115
+ 15 2 63 3 94 11 139 20 150 0 58
+ 16 2 37 0 56 5 78 10 102 0 39
+ 17 0 18 0 28 4 57 8 80 0 15
+ 18 0 8 0 17 2 50 6 56 0 12
+ 19 0 9 0 5 0 19 0 48 0 18
+ 20 0 4 0 8 0 11 2 27 0 4
+ 21 0 2 0 3 1 9 1 18 0 6
+ 22 0 1 0 3 1 7 0 3 0 5
+ 23 0 2 0 4 0 2 0 7 0 2
+ 24 0 2 0 2 1 3 0 3 0 5
+ 25 0 0 0 1 0 1 0 1 0 3
+ 26 0 1 0 0 0 2 0 2 0 0
+ 27 0 0 0 3 0 1 0 0 0 1
+ 28 0 0 0 3 0 0 0 1 0 0
+ 29 0 0 0 2 0 2 0 1 0 3
+ 30 0 1 0 0 0 0 0 0 0 0
+ 31 0 1 0 0 0 0 0 2 0 2
+ 32 0 0 0 1 0 2 0 0 0 0
+ 33 0 0 0 2 0 0 0 0 0 1
+ 34 0 0 0 0 0 0 0 0 0 2
+ 35 0 1 0 1 0 0 0 0 0 1
+ 36 0 1 0 0 0 1 0 1 0 0
+ 37 0 0 0 1 0 0 0 0 0 0
+ 40 0 0 0 0 0 1 0 1 0 0
+ 41 0 0 0 0 0 0 0 0 0 1
+ 42 0 0 0 0 0 0 0 0 0 1
+ 44 0 0 0 0 0 1 0 0 0 0
+ 46 0 0 0 0 0 0 0 1 0 0
+ 47 0 0 0 0 0 0 0 0 0 1
+ 50 0 0 0 0 0 0 0 0 0 1
+ 54 0 0 0 1 0 0 0 0 0 0
+ 58 0 0 0 1 0 0 0 0 0 0
+ over: 0 0 0 0 0 0 0 0 0 0
+ count: 600002 600002 600002 600002 600002 600002 600002 600002 600002 600002
+ min: 0 1 0 1 0 1 0 1 0 1
+ avg: 0 5 0 5 0 4 0 4 0 5
+ max: 16 36 15 58 24 44 21 46 13 50
+
+SEE ALSO
+========
+**rtla-timerlat**\(1), **rtla-timerlat-top**\(1)
+
+*timerlat* tracer documentation: <https://www.kernel.org/doc/html/latest/trace/timerlat-tracer.html>
+
+AUTHOR
+======
+Written by Daniel Bristot de Oliveira <bristot@kernel.org>
diff --git a/Documentation/tools/rtla/rtla-timerlat-top.rst b/Documentation/tools/rtla/rtla-timerlat-top.rst
new file mode 100644
index 000000000..7c4e4b109
--- /dev/null
+++ b/Documentation/tools/rtla/rtla-timerlat-top.rst
@@ -0,0 +1,145 @@
+====================
+rtla-timerlat-top
+====================
+-------------------------------------------
+Measures the operating system timer latency
+-------------------------------------------
+
+:Manual section: 1
+
+SYNOPSIS
+========
+**rtla timerlat top** [*OPTIONS*] ...
+
+DESCRIPTION
+===========
+
+.. include:: common_timerlat_description.rst
+
+The **rtla timerlat top** displays a summary of the periodic output
+from the *timerlat* tracer. It also provides information for each
+operating system noise via the **osnoise:** tracepoints that can be
+seem with the option **-T**.
+
+OPTIONS
+=======
+
+.. include:: common_timerlat_options.rst
+
+.. include:: common_top_options.rst
+
+.. include:: common_options.rst
+
+EXAMPLE
+=======
+
+In the example below, the *timerlat* tracer is set to capture the stack trace at
+the IRQ handler, printing it to the buffer if the *Thread* timer latency is
+higher than *30 us*. It is also set to stop the session if a *Thread* timer
+latency higher than *30 us* is hit. Finally, it is set to save the trace
+buffer if the stop condition is hit::
+
+ [root@alien ~]# rtla timerlat top -s 30 -T 30 -t
+ Timer Latency
+ 0 00:00:59 | IRQ Timer Latency (us) | Thread Timer Latency (us)
+ CPU COUNT | cur min avg max | cur min avg max
+ 0 #58634 | 1 0 1 10 | 11 2 10 23
+ 1 #58634 | 1 0 1 9 | 12 2 9 23
+ 2 #58634 | 0 0 1 11 | 10 2 9 23
+ 3 #58634 | 1 0 1 11 | 11 2 9 24
+ 4 #58634 | 1 0 1 10 | 11 2 9 26
+ 5 #58634 | 1 0 1 8 | 10 2 9 25
+ 6 #58634 | 12 0 1 12 | 30 2 10 30 <--- CPU with spike
+ 7 #58634 | 1 0 1 9 | 11 2 9 23
+ 8 #58633 | 1 0 1 9 | 11 2 9 26
+ 9 #58633 | 1 0 1 9 | 10 2 9 26
+ 10 #58633 | 1 0 1 13 | 11 2 9 28
+ 11 #58633 | 1 0 1 13 | 12 2 9 24
+ 12 #58633 | 1 0 1 8 | 10 2 9 23
+ 13 #58633 | 1 0 1 10 | 10 2 9 22
+ 14 #58633 | 1 0 1 18 | 12 2 9 27
+ 15 #58633 | 1 0 1 10 | 11 2 9 28
+ 16 #58633 | 0 0 1 11 | 7 2 9 26
+ 17 #58633 | 1 0 1 13 | 10 2 9 24
+ 18 #58633 | 1 0 1 9 | 13 2 9 22
+ 19 #58633 | 1 0 1 10 | 11 2 9 23
+ 20 #58633 | 1 0 1 12 | 11 2 9 28
+ 21 #58633 | 1 0 1 14 | 11 2 9 24
+ 22 #58633 | 1 0 1 8 | 11 2 9 22
+ 23 #58633 | 1 0 1 10 | 11 2 9 27
+ timerlat hit stop tracing
+ saving trace to timerlat_trace.txt
+ [root@alien bristot]# tail -60 timerlat_trace.txt
+ [...]
+ timerlat/5-79755 [005] ....... 426.271226: #58634 context thread timer_latency 10823 ns
+ sh-109404 [006] dnLh213 426.271247: #58634 context irq timer_latency 12505 ns
+ sh-109404 [006] dNLh313 426.271258: irq_noise: local_timer:236 start 426.271245463 duration 12553 ns
+ sh-109404 [006] d...313 426.271263: thread_noise: sh:109404 start 426.271245853 duration 4769 ns
+ timerlat/6-79756 [006] ....... 426.271264: #58634 context thread timer_latency 30328 ns
+ timerlat/6-79756 [006] ....1.. 426.271265: <stack trace>
+ => timerlat_irq
+ => __hrtimer_run_queues
+ => hrtimer_interrupt
+ => __sysvec_apic_timer_interrupt
+ => sysvec_apic_timer_interrupt
+ => asm_sysvec_apic_timer_interrupt
+ => _raw_spin_unlock_irqrestore <---- spinlock that disabled interrupt.
+ => try_to_wake_up
+ => autoremove_wake_function
+ => __wake_up_common
+ => __wake_up_common_lock
+ => ep_poll_callback
+ => __wake_up_common
+ => __wake_up_common_lock
+ => fsnotify_add_event
+ => inotify_handle_inode_event
+ => fsnotify
+ => __fsnotify_parent
+ => __fput
+ => task_work_run
+ => exit_to_user_mode_prepare
+ => syscall_exit_to_user_mode
+ => do_syscall_64
+ => entry_SYSCALL_64_after_hwframe
+ => 0x7265000001378c
+ => 0x10000cea7
+ => 0x25a00000204a
+ => 0x12e302d00000000
+ => 0x19b51010901b6
+ => 0x283ce00726500
+ => 0x61ea308872
+ => 0x00000fe3
+ bash-109109 [007] d..h... 426.271265: #58634 context irq timer_latency 1211 ns
+ timerlat/6-79756 [006] ....... 426.271267: timerlat_main: stop tracing hit on cpu 6
+
+In the trace, it is possible the notice that the *IRQ* timer latency was
+already high, accounting *12505 ns*. The IRQ delay was caused by the
+*bash-109109* process that disabled IRQs in the wake-up path
+(*_try_to_wake_up()* function). The duration of the IRQ handler that woke
+up the timerlat thread, informed with the **osnoise:irq_noise** event, was
+also high and added more *12553 ns* to the Thread latency. Finally, the
+**osnoise:thread_noise** added by the currently running thread (including
+the scheduling overhead) added more *4769 ns*. Summing up these values,
+the *Thread* timer latency accounted for *30328 ns*.
+
+The primary reason for this high value is the wake-up path that was hit
+twice during this case: when the *bash-109109* was waking up a thread
+and then when the *timerlat* thread was awakened. This information can
+then be used as the starting point of a more fine-grained analysis.
+
+Note that **rtla timerlat** was dispatched without changing *timerlat* tracer
+threads' priority. That is generally not needed because these threads hava
+priority *FIFO:95* by default, which is a common priority used by real-time
+kernel developers to analyze scheduling delays.
+
+SEE ALSO
+--------
+**rtla-timerlat**\(1), **rtla-timerlat-hist**\(1)
+
+*timerlat* tracer documentation: <https://www.kernel.org/doc/html/latest/trace/timerlat-tracer.html>
+
+AUTHOR
+------
+Written by Daniel Bristot de Oliveira <bristot@kernel.org>
+
+.. include:: common_appendix.rst
diff --git a/Documentation/tools/rtla/rtla-timerlat.rst b/Documentation/tools/rtla/rtla-timerlat.rst
new file mode 100644
index 000000000..44a49e6f3
--- /dev/null
+++ b/Documentation/tools/rtla/rtla-timerlat.rst
@@ -0,0 +1,57 @@
+================
+rtla-timerlat
+================
+-------------------------------------------
+Measures the operating system timer latency
+-------------------------------------------
+
+:Manual section: 1
+
+SYNOPSIS
+========
+**rtla timerlat** [*MODE*] ...
+
+DESCRIPTION
+===========
+
+.. include:: common_timerlat_description.rst
+
+The *timerlat* tracer outputs information in two ways. It periodically
+prints the timer latency at the timer *IRQ* handler and the *Thread* handler.
+It also provides information for each noise via the **osnoise:** tracepoints.
+The **rtla timerlat top** mode displays a summary of the periodic output
+from the *timerlat* tracer. The **rtla hist hist** mode displays a histogram
+of each tracer event occurrence. For further details, please refer to the
+respective man page.
+
+MODES
+=====
+**top**
+
+ Prints the summary from *timerlat* tracer.
+
+**hist**
+
+ Prints a histogram of timerlat samples.
+
+If no *MODE* is given, the top mode is called, passing the arguments.
+
+OPTIONS
+=======
+**-h**, **--help**
+
+ Display the help text.
+
+For other options, see the man page for the corresponding mode.
+
+SEE ALSO
+========
+**rtla-timerlat-top**\(1), **rtla-timerlat-hist**\(1)
+
+*timerlat* tracer documentation: <https://www.kernel.org/doc/html/latest/trace/timerlat-tracer.html>
+
+AUTHOR
+======
+Written by Daniel Bristot de Oliveira <bristot@kernel.org>
+
+.. include:: common_appendix.rst
diff --git a/Documentation/tools/rtla/rtla.rst b/Documentation/tools/rtla/rtla.rst
new file mode 100644
index 000000000..fc0d233ef
--- /dev/null
+++ b/Documentation/tools/rtla/rtla.rst
@@ -0,0 +1,48 @@
+=========
+rtla
+=========
+--------------------------------
+Real-time Linux Analysis tool
+--------------------------------
+
+:Manual section: 1
+
+SYNOPSIS
+========
+**rtla** *COMMAND* [*OPTIONS*]
+
+DESCRIPTION
+===========
+The **rtla** is a meta-tool that includes a set of commands that aims to
+analyze the real-time properties of Linux. But instead of testing Linux
+as a black box, **rtla** leverages kernel tracing capabilities to provide
+precise information about the properties and root causes of unexpected
+results.
+
+COMMANDS
+========
+**osnoise**
+
+ Gives information about the operating system noise (osnoise).
+
+**timerlat**
+
+ Measures the IRQ and thread timer latency.
+
+OPTIONS
+=======
+**-h**, **--help**
+
+ Display the help text.
+
+For other options, see the man page for the corresponding command.
+
+SEE ALSO
+========
+**rtla-osnoise**\(1), **rtla-timerlat**\(1)
+
+AUTHOR
+======
+Daniel Bristot de Oliveira <bristot@kernel.org>
+
+.. include:: common_appendix.rst