On Tue, 2007-08-21 at 16:05 +1000, Dave Airlie wrote:
So you can see why some sort of uncached+writecombined page cache
would be useful, I could just allocate a bunch of pages at startup as
uncached+writecombined, and allocate pixmaps from them and when I
bind/free the pixmap I don't need the flush at all, now I'd really
like this to be part of the VM so that under memory pressure it can
just take the pages I've got in my cache back and after flushing turn
them back into cached pages, the other option is for the DRM to do
this on its own and penalise the whole system.
Can't you make these pages part of the regular VM by sticking them all
into an address_space.
And for this reclaim behaviour you'd only need to set PG_private and
have a_ops->releasepage() dtrt.