linux-kernel - Re: [PATCH] backlight dimmer

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Sun, 28 Oct 2007 23:09:53 +0100
From:	jack@...onello.org
To:	Arjan van de Ven <arjan@...radead.org>
CC:	"lists@...onello.org" <lists@...onello.org>,
	Samuel Tardieu <sam@...1149.net>, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] backlight dimmer

Arjan van de Ven wrote:
> On Sun, 28 Oct 2007 22:30:55 +0100
> "lists@...onello.org" <lists@...onello.org> wrote:
> 
>> Ok,
>>   now checkpatch.pl only complains about a missing signed-off-by.
>> Is this ok for review?
> 
> 
> hi,
> 
> when going over your patch.. is there a reason you introduce yet
> another timeout infrastructure? Is there something wrong with the
> existing ones that maybe should be fixed instead?
> Either way.. please put justification for such new mechanism in the
> patch changelog....
> 
> Greetings,
>    Arjan van de Ven
> 

hi,

i don't think there are similar infrastructures. This timeout is
not quite a timer.

The timeout starts counting when timeout_touch() is first called. At
this point the start() function is executed in non-atomic context.
Then either it is reset if timeout_touch() is called in time (and
thus starts to count again). Else it triggers, and executes the
trigger() function in non-atomic context and it stays idle unless
timeout_touch() is called again.

The non-atomic context is needed to use backlight.c mutexes and
that is enabled with the use of workqueues.

I don't mean to add some new infrastructure to the base kernel, but
it seemed a general functionality to me. In fact it may also be fully
included in backlight.c. Since backlight.h is in include/linux, i was
forced to put timeout.h in include/linux also. But this is just
a temporary fix.

jacopo

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/