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Date:   Tue, 7 Apr 2020 13:40:28 -0600
From:   Jonathan Corbet <corbet@lwn.net>
To:     Daniel Bristot de Oliveira <bristot@redhat.com>
Cc:     Peter Zijlstra <peterz@infradead.org>,
        John Mathew <john.mathew@unikie.com>,
        linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org,
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        tsbogend@alpha.franken.de, lukas.bulwahn@gmail.com, x86@kernel.org,
        linux-mips@vger.kernel.org, tglx@linutronix.de,
        mostafa.chamanara@basemark.com
Subject: Re: [RFC PATCH 2/3] docs: scheduler: Add scheduler overview
 documentation
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On Wed, 1 Apr 2020 13:47:04 +0200
Daniel Bristot de Oliveira <bristot@redhat.com> wrote:

> > And that is a prime example of why I hates RST, it pretty much mandates
> > you view this with something other than a text editor.  
> 
> The good thing about the dot format is that we can convert it to many other
> formats, including text:
> 
> [bristot@x1 ~]$ cat sched_transition.dot | graph-easy 
> 
>                        *
> 
>                        |
>                        | task
>                        | forks
>                        v
>                      +------------------------------------+
>                      |              TASK_NEW              |
>                      |           (Ready to run)           |
>                      +------------------------------------+
>                        |
>                        |
>                        v
> + - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -+
> '                                     int                                            '
> '                                                                                    '
> '                    +------------------------------------+                          '
> '                    |            TASK_RUNNING            |                          '
> '   +--------------> |           (Ready to run)           | <--+                     '
> '   |                +------------------------------------+    |                     '
> '   |                  |                                       |                     '
> '   |                  | schedule() calls context_switch()     | task is pre-empted  '
> '   |                  v                                       |                     '
> '   |                +------------------------------------+    |                     '
> '   |                |            TASK_RUNNING            |    |                     '
> '   |                |             (Running)              | ---+                     '
> '   | event occurred +------------------------------------+                          '
> '   |                  |                                                             '
> '   |                  |                                      - - - - - - - - - - - -+
> '   |                  |                                    '
> '   |                  | task needs to wait for event       '
> '   |                  v                                    '
> '   |                +------------------------------------+ '
> '   |                |         TASK_INTERRUPTIBLE         | '
> '   |                |        TASK_UNINTERRUPTIBLE        | '
> '   +--------------- |           TASK_WAKEKILL            | '
> '                    +------------------------------------+ '
> '                                                           '
> + - - - - - - - - - - - - - - - - - - - - - - - - - - - - - +
>                        |
>                        | task exits via do_exit()
>                        v
>                      +------------------------------------+
>                      |             TASK_DEAD              |
>                      |            EXIT_ZOMBIE             |
>                      +------------------------------------+
> 
> 
> Is there a way to also add this representation, while hiding it
> when using a graphical reader?

Better, honestly, to just put the ascii art into the doc as a literal
block.  I don't see any real reason to embed Dot stuff unless there's
really no alternative.

Thanks,

jon