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Re: some changes for (slightly) faster boot



Alan Cox (alan redhat com) said: 
> On Tue, Jan 04, 2005 at 09:58:43PM -0500, Bill Nottingham wrote:
> >   - because you never get a 'this driver is done creating devices'
> >     signal, you need to either
> >     a) sleep a random amount of time
> >     b) run the restore command multiple times
> 
> A driver is never done, this is hotplug. I can plug in USB audio any time I
> like. Now what could be done if this would help (you tell me as guru of 
> initscripting) is to tell the userspace "the initial device enumeration
> is done". In fact in most cases this would be in the standard pci_foo code.

Basically, for any ALSA driver, it creates various device nodes; control
nodes, PCM nodes, etc. These device nodes appear to be created in a different
order depending on the driver (or perhaps the udev events are getting
reordered). While the device you use to set the mixer is the control
device, the device isn't actually available until some point later
after various other device nodes are created. So, some sort of
"i'm done with device nodes for this one physical device" signal
would be nice.

> >      - has made random device nodes for them and trusted
> >        that kmod works. So, what exactly was the point of a dynamic
> >        /dev then?
> 
> Nobody in the kernel world ever thought of udev as a "solely dynamic" world
> to my knowledge but as a partially dynamic one.

I've seen rumblings that kmod was slated for removal, though, which
means that the only other option would be to load all non-physical
devices unilaterally. This seems subpar.

Bill


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