From: Valentin Schneider <valentin.schneider@arm.com>
To: Julia Lawall <julia.lawall@lip6.fr>
Cc: Markus Elfring <Markus.Elfring@web.de>,
Alexey Dobriyan <adobriyan@gmail.com>,
dm-devel@redhat.com, linux-block@vger.kernel.org,
rcu@vger.kernel.org, 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>
Subject: Re: sched: make struct task_struct::state 32-bit
Date: Mon, 23 Sep 2019 12:26:44 +0100 [thread overview]
Message-ID: <d529c390-546e-a8a4-f475-c3ee41f97645@arm.com> (raw)
In-Reply-To: <alpine.DEB.2.21.1909231228200.2272@hadrien>
On 23/09/2019 11:34, Julia Lawall wrote:
>> // FIXME: current not recognized as task_struct*, fixhack with regexp
>> identifier current =~ "^current$";
>
> Please don't do this. Just use the word current. It doesn't have to be a
> metavariable. You will though get a warning about it. To eliminate the
> warning, you can say symbol current;
>
Didn't know about that way to get rid of the warning, thanks!
>> identifier task_state =~ "^TASK_";
>
> Are there a lot of options? You can also enumerate them in {}, ie
>
> identifier task_state = {TASK_BLAH, TASK_BLAHBLAH};
>
Around a dozen, can be enumerated easily and is indeed probably better than
a regexp.
>> identifier state_var;
>> position pos;
>> @@
>>
>> (
>> p->state & state_var@pos
>> |
>> current->state & state_var@pos
>> |
>> p->state | state_var@pos
>> |
>> current->state | state_var@pos
>> |
>> p->state < state_var@pos
>> |
>> current->state < state_var@pos
>> |
>> p->state > state_var@pos
>> |
>> current->state > state_var@pos
>> |
>> state_var@pos = p->state
>> |
>> state_var@pos = current->state
>> |
>> p->state == state_var@pos
>> |
>> current->state == state_var@pos
>> |
>> p->state != state_var@pos
>> |
>> current->state != state_var@pos
>> |
>> // FIXME: match functions that do something with state_var underneath?
>> // How to do recursive rules?
>
> You want to look at the definitions of called functions? Coccinelle
> doesn't really support that, but there are hackish ways to add that. How
> many function calls would you expect have to be unrolled?
>
I wouldn't expect more than a handful (~5). I suppose this has to do with
injecting some Python/Ocaml code? I have some examples bookmarked but
haven't gotten to stare at them long enough.
>> set_current_state(state_var@pos)
>> |
>> set_special_state(state_var@pos)
>> |
>> signal_pending_state(state_var@pos, p)
>> |
>> signal_pending_state(state_var@pos, current)
>> |
>> state_var@pos & task_state
>> |
>> state_var@pos | task_state
>> )
>>
>> // Fixup local variables
>> @depends on patch && state_access@
>> identifier state_var = state_access.state_var;
>> @@
>> (
>> - long
>> + int
>> |
>> - unsigned long
>> + unsigned int
>> )
>> state_var;
>>
>> // Fixup function parameters
>> @depends on patch && state_access@
>> identifier fn;
>> identifier state_var = state_access.state_var;
>> @@
>>
>> fn(...,
>> - long state_var
>> + int state_var
>> ,...)
>> {
>> ...
>> }
>>
>> // FIXME: find a way to squash that with the above?
>
> I think that you can make a disjunction on a function parameter
>
> fn(...,
> (
> - T1 x1
> + T2 x2
> |
> - T3 x3
> + T4 x4
> )
> , ...) { ... }
>
My attempt at this gives me "minus: parse error", which is why I went
with the split.
Something simple like this works:
---
virtual patch
virtual report
@@
identifier fn;
identifier p;
@@
fn(...,
- long
+ int
p
,...)
{
...
}
---
but this doesn't:
---
virtual patch
virtual report
@@
identifier fn;
identifier p;
@@
fn(...,
(
- long p
+ int p
|
- unsigned long p
+ unsigned int p
)
,...)
{
...
}
---
> julia
>
next prev parent reply other threads:[~2019-09-23 11:26 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-09-02 21:05 [PATCH] sched: make struct task_struct::state 32-bit Alexey Dobriyan
2019-09-02 23:02 ` Valentin Schneider
2019-09-03 16:23 ` Alexey Dobriyan
2019-09-03 16:31 ` Valentin Schneider
2019-09-03 6:51 ` [dm-devel] " Christoph Hellwig
2019-09-03 7:13 ` Peter Zijlstra
2019-09-03 17:29 ` Valentin Schneider
2019-09-03 18:19 ` Alexey Dobriyan
2019-09-03 21:51 ` Valentin Schneider
2019-09-04 12:07 ` Valentin Schneider
2019-09-04 17:48 ` Valentin Schneider
2019-09-05 15:51 ` Markus Elfring
2019-09-05 16:52 ` Valentin Schneider
2019-09-23 10:26 ` Valentin Schneider
2019-09-23 10:34 ` Julia Lawall
2019-09-23 11:26 ` Valentin Schneider [this message]
2019-09-23 11:43 ` Julia Lawall
2019-09-23 13:23 ` Valentin Schneider
2019-09-24 8:28 ` Markus Elfring
2019-09-24 8:07 ` Markus Elfring
2019-09-04 9:43 ` [PATCH] " David Laight
2019-09-04 10:25 ` Valentin Schneider
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=d529c390-546e-a8a4-f475-c3ee41f97645@arm.com \
--to=valentin.schneider@arm.com \
--cc=Markus.Elfring@web.de \
--cc=aarcange@redhat.com \
--cc=adobriyan@gmail.com \
--cc=axboe@kernel.dk \
--cc=dm-devel@redhat.com \
--cc=julia.lawall@lip6.fr \
--cc=linux-block@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=peterz@infradead.org \
--cc=rcu@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).