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Subject: Re: sched: make struct task_struct::state 32-bit
To:     Valentin Schneider <valentin.schneider@arm.com>,
        Alexey Dobriyan <adobriyan@gmail.com>, dm-devel@redhat.com,
        linux-block@vger.kernel.org, rcu@vger.kernel.org
Cc:     linux-kernel@vger.kernel.org,
        Andrea Arcangeli <aarcange@redhat.com>,
        Ingo Molnar <mingo@redhat.com>, Jens Axboe <axboe@kernel.dk>,
        Peter Zijlstra <peterz@infradead.org>,
        Julia Lawall <julia.lawall@lip6.fr>
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From:   Markus Elfring <Markus.Elfring@web.de>
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Date:   Tue, 24 Sep 2019 10:07:54 +0200
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> // FIXME: current not recognized as task_struct*, fixhack with regexp
> identifier current =3D~ "^current$";

Would you really like to use a regular expression for finding a single wor=
d?


> identifier state_var;
> position pos;
> @@
>
> (
>   p->state & state_var@pos
> |
>   current->state & state_var@pos
> |

I see further opportunities to make such a SmPL disjunction more succinct.

*
( ( \( p \| current \) ) -> state & state_var@pos
|
=E2=80=A6

* How do you think about to work with a SmPL constraint
  for a metavariable with the type =E2=80=9Cbinary operator=E2=80=9D?


>   set_current_state(state_var@pos)
> |
>   set_special_state(state_var@pos)

| \( set_current_state \| set_special_state \) (state_var@pos)


> |
>   signal_pending_state(state_var@pos, p)
> |
>   signal_pending_state(state_var@pos, current)

| signal_pending_state(state_var@pos, \( p \| current \) )


Regards,
Markus