Re: [Qemu-devel] [PATCH v4 00/22] Steps towards per CPU address-spaces

[Edgar E. Iglesias]

On Mon, Feb 10, 2014 at 11:42:35PM +0000, Peter Maydell wrote:
> On 10 February 2014 23:10, Edgar E. Iglesias <address@hidden> wrote:
> > My thinking was in terms of trying to minimize the amount of
> > AS structures we create in cases were the nr of master outnumber
> > the nr of ASs. But there might be ways to achieve being light
> > even if we dont explicitely pass AS refs around. Will try to get
> > a chance to look at a MemoryRegion based interface instead
> > (if no one beats me to it).
> 
> 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).

Cheers,
Edgar