> > What do the kernel developers think about that ?
>
> Right now, they are focused on getting 2.4 out the door. The
> rawio stuff (kiobufs, kiovecs) that went into 2.3/2.4 is a step in the
> right direction - it allows userspace to have much more fine-grained
> control over the low-level VM mappings (pagetables, physical-to-virtual
> page mappings, page cacheing, etc) of memory mapped files. But I have
> not seen any mention of such a comprehensive "page coloring" or "page
> tagging" system as I proposed. Lots of driver subsystems could make
> their memory-management routines much more generic if such a system was
> present....
Code freeze!!!! At work I have spent a good amount of time with
several IDE developers so now I know kiobufs etc very well. It is a true
god send. Also kiobufs are what IRIX uses to drive the DMA engines on
graphcis cards. BTW this is where the locking is really used in IRIX. The
DRI people got confussed. You have to pin the kiobufs in userspace so they
don't get swapped out. The really nice thing about kiobufs is that they
totally bypass the VM layer and talk directly to the page handling
routines. Huge performance gains :-) Page tagging and page coloring are in
the works for 2.5.X. Rik Riel is working on it.
> > Are they totally satisfied with the current state ?
>
> Linus appears to be happy to let the DRI people deal with this
> sort of thing for now. Their system is a _little_ more powerful than
> /dev/agpgart (they implement some generic reader/writer locking and
> synchronized DMA flushes), but not much.
Linus is devoted to the idea of the DRI. I guess you didn't see my thread
in December of last year about DRI. BTW I won that debate with him. After
I'm done with rewriting the console layer for linux I will begin work on
a new graphics system for linux. First the mix of the graphics system and
the console system needs to go away.
> > Or do they
> > assume that there is no life after X ? ;)
>
> It seems that way.
Yes :-( Linus will die by X. He considers it the only important app for
linux.
