Re: [Qemu-devel] [Qemu-ppc] [PATCH 08/12] target-ppc: Convert ppcemb_tlb_t to use fixed 64-bit RPN

[Alexander Graf]

On 19.11.2012, at 23:48, David Gibson wrote:

> On Mon, Nov 19, 2012 at 05:26:45PM +0100, Alexander Graf wrote:
>> 
>> On 13.11.2012, at 03:46, David Gibson wrote:
>> 
>>> Currently the ppcemb_tlb_t struct, used on a number of embedded ppc models
>>> to represent a TLB entry contains a hwaddr.  That works reasonably for now,
>>> but is troublesome for saving the state, which we'll want to do in future.
>>> hwaddr is a large enough type to contain a physical address for any
>>> supported machine - and can thus, in theory at least, vary depending on
>>> what machines are enabled other than the one we're actually using right
>>> now (though in fact it doesn't for ppc).  This makes it unsuitable for
>>> describing in vmstate.
>>> 
>>> This patch therefore changes ppcemb_tlb_t to use a fixed 64-bit integer
>>> which we know is sufficient for all the machines which use this structure.
>> 
>> hwaddr is always defined to 64bit by now.
> 
> I know, but there aren't state save helpers for hwaddr, and there are
> objections to creating them.

Sure, but you can just use the 64bit save helpers now that hwaddr == uint64_t, 
no?

The reason I'm reluctant is that this is not the only case where we have an 
hwaddr field in the CPUState struct. Either we convert all the hwaddr fields 
that we potentially want to savevm/loadvm or we don't convert any :).


Alex