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From: James Courtier-Dutton <James@superbug.co.uk>
To: Lee Revell <rlrevell@joe-job.com>
Cc: alsa-devel <alsa-devel@lists.sourceforge.net>
Subject: Re: Question about kernel timers
Date: Fri, 28 Jul 2006 09:00:03 +0100	[thread overview]
Message-ID: <44C9C403.8040301@superbug.co.uk> (raw)
In-Reply-To: <1153864917.25859.238.camel@mindpipe>

Lee Revell wrote:
> I am writing a driver in which every time some event occurs, two
> single-shot timers must be scheduled.  This event could happen many
> times per second so many of these timers can be pending at once.  Can
> someone point me to an example of a driver that does something like
> this?
> 
> All the ALSA drivers I can find that use timers have a single periodic
> timer and use a struct timer_list in the card record.  However I think
> this is not an option for me, as I must create new timers on the fly.
> 
> I've found that the kernel Oopses if you allocate a timer on the stack,
> so I use kmalloc().  It seems to work, but leaks memory, as there's no
> opportunity to free() all the timer_lists I'm creating on the fly.
> 
> Can I do this with a single struct timer_list?  Is it possible to
> schedule multiple timers using add_timer() then changing the parameters
> and add_timer() again?
> 
> It seems that this should be documented somewhere but it's not - LDD3
> was no help.  All the examples were very simplistic.
> 
> Lee
> 

What is the purpose of these event timers?
I can't think of any sound card that needs this sort of stuff.
Can you use polling instead?

James


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  parent reply	other threads:[~2006-07-28  8:00 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2006-07-25 22:01 Question about kernel timers Lee Revell
2006-07-28  1:18 ` Lee Revell
2006-07-28  7:01   ` Clemens Ladisch
2006-07-28  8:00 ` James Courtier-Dutton [this message]
2006-07-28 15:14   ` Lee Revell
2006-07-28 10:06 ` Takashi Iwai

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