Re: udev is too slow creating devices

["Alexander E. Patrakov" <patrakov@ums.usu.ru>]

Ihar 'Philips' Filipau wrote:
> Benjamin Herrenschmidt wrote:
> 
>>
>> Nope, Greg is right. Drivers themselves won't necessarily provide
>> you with the device interface in a synchronous way after they are
>> loaded, and some will certainly never. It is all an asynchronous process
>> and there is simply no way to ask for any kind of enforced synchronicity
>> here without major bloatage.
>>
> 
>   Okay, okay. Let's spread delays and polling all over numerous init 
> scripts.

I read it as "Let's bloat initscripts instead of the kernel". We 
probably have to bloat something, but we don't want to bloat our 
favourite kernel.

Maybe we should create a bash file with functions that implement it "the 
right way" and distribute this file with udev as an example?

>   You might be ten thousands time right. It is asynchronous process.
> 
>   But please listen to me: you are not going to handle that in _every_ 
> system application which deals with modules.

We should probably avoid code duplication and put this functionality 
into a library (maybe even glibc?)

What we currently see is that distros either ignore the race or (like 
LFS) say something like:

"Because of all those compilcations with Hotplug, Udev and modules, we 
strongly recommend you to start with a completely non-modular kernel 
configuration, especially if this is the first time you use Udev."

-- 
Alexander E. Patrakov