Re: NetBSD drivers on HURD?

[Daniel Wagner]

> When it comes to libfthread, I haven't really looked at it much.  To tell
> the truth, I haven't looked at deva/fabrica's code much, because I am
> trying to understand the core part of the Hurd/L4 first.  However, if it's
> a threading library, wouldn't it make more sense to put threading calls
> into deva and have deva make the appropriate threading calls on each OS, or
> is libfthread necessary to create a faster version of threading for the
> purpose of the device drivers?

The threading library provides a nicer/richer interface to the deva 
interfaces. Basically, you need to talk to the deva server from your drivers. 
This communication can be wrapped with the threading library. Note, that the 
calls to create new threads etc were also planned to go through deva to end 
up in the OS. What you described is what the library should have been...


> I'm basically trying to understand about a couple things in order to reach
> a possible compromise in the design:
> 1) If I create the threading library, I'll have to make it work on multiple
> architectures, doing essentially parallel work to most OS out there.  Is it
> worth me doing that?

If you want to have drivers for other OSes this makes sens. If you want to 
support only Hurd/L4 the answer is no.

> 2) Does libfthread offer an advantage over normal OS threading libraries?

Yes, you don't need everything, you can use a very lightweight version which 
is optimised for driver use (whatever that means).

daniel