rtla: Add rtla timerlat hist documentation

Man page for rtla timerlat hist mode.

Link: https://lkml.kernel.org/r/[e-mail]

Cc: Tao Zhou <[e-mail]>
Cc: Ingo Molnar <[e-mail]>
Cc: Tom Zanussi <[e-mail]>
Cc: Masami Hiramatsu <[e-mail]>
Cc: Juri Lelli <[e-mail]>
Cc: Clark Williams <[e-mail]>
Cc: John Kacur <[e-mail]>
Cc: Peter Zijlstra <[e-mail]>
Cc: Thomas Gleixner <[e-mail]>
Cc: Sebastian Andrzej Siewior <[e-mail]>
Cc: Daniel Bristot de Oliveira <[e-mail]>
Cc: [e-mail]
Cc: [e-mail]
Cc: [e-mail]
Signed-off-by: Daniel Bristot de Oliveira <[e-mail]>
Signed-off-by: Steven Rostedt <[e-mail]>

Documentation/tools/rtla/rtla-timerlat-hist.rst

···
+=====================
+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 *timelat* 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 <[e-mail]>