Re: udev is too slow creating devices

From: Greg KH
Date: Wed Sep 15 2004 - 11:26:47 EST


On Wed, Sep 15, 2004 at 05:45:03PM +0200, Giacomo A. Catenazzi wrote:
>
>
> Tonnerre wrote:
> >
> >On Wed, Sep 15, 2004 at 03:36:06PM +0100, Ian Campbell wrote:
> >
> >>I wonder if it would be feasible for modprobe (or some other utility) to
> >>have a new option: --wait-for=/dev/something which would wait for the
> >>device node to appear. Perhaps by:
> >> - some mechanism based on HAL, DBUS, whatever
> >> - dnotify on /dev/?
> >> - falling back to spinning and waiting.
> >
> >
> >This would end up as hideous misfeature as you can't guarantee the
> >device to show up *at* *all*.
> >
> >The reason udev is there is that we can dynamically respond to created
> >device nodes and devices that show up. They might have changed since
> >the last boot. Maybe they don't show up at all.
> >
> >Thus you should trigger your actions from /etc/dev.d.
>
> It is right.
> But an option --wait would be sufficient.
> This option will require modprobe to wait (with a timeout of
> x seconds) that hotplug event finish (so if device is created or
> not is no more a problem).
> Ideally this should be done modifing only hotplug and IMHO
> should be enabled by default.

Um, I don't think this is posible to do at all. But hey, go ahead and
implement it to prove me wrong :)

good luck,

greg k-h
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