Il 11/02/2014 00:53, Edgar E. Iglesias ha scritto:
> Is there that much overhead to creating an AS per master? I guess
> you end up recalculating the same memory flatview for every AS
> when a memory region gets mapped or unmapped.
> In any case, if it's OK to share AddressSpaces between masters
> then we can relatively easily do so, since there's already a list
> of all AddressSpaces that you can run through to find the one
> whose root MemoryRegion is the one you want. (Probably needs
> a refcount in the AddressSpace struct as well.)
Right, something like that might be worthwhile.
It might not make much difference until we start ramping
things up significantly (in terms of amount of masters).
We already have a decent amount of masters for PCI, where each device
that can do bus-master DMA has basically its own copy of
address_space_memory. It has never been a problem in terms of time
spent updating the ASes.
Paolo
