re: merge coming soon: jmcneill-usbmp

[matthew green <mrg%eterna.com.au@localhost>]

>         - usbd_bus_methods{} gains a get_lock() to enable the
>           host controller to provide a lock for the USB code.
>           if the lock isn't provided, old-style protection is
>           (partially) applied.
> 
> It is better if the USB driver can select the lock, like in FreeBSD. Else you 
> run into some atomic races when two SMP'enabled stacks are talking to 
> eachother, like a SMP-CAM layer and a SMP-USB stack.

can you expand a little on what sort of races you mean?  for me, i
originally helped with this effort so we could talk to the recently
commited MP audio stack.

> Has the FreeBSD's USB stack been evaluated when doing this NetBSD smp-ng, or 
> is this just a simple effort to try to get things a bit better than is now?

the latter.  i'm not a USB person, and didn't really expect to come
the owner of this project when i started helping :)  the TODO.usbmp
has quite a few non trivial items in it, but those are more about
enabling device-specific MP support at this point.

thanks.


.mrg.