Re: [PATCH RFC 2/9] xen: Optimize introspection access to guest state

[Razvan Cojocaru <rcojocaru@bitdefender.com>]

On 07/02/2014 06:31 PM, Andrew Cooper wrote:
> On 02/07/14 14:33, Razvan Cojocaru wrote:
>> Speed optimization for introspection purposes: a handful of registers
>> are sent along with each mem_event. This requires enlargement of the
>> mem_event_request / mem_event_response stuctures, and additional code
>> to fill in relevant values.
>>
>> Signed-off-by: Razvan Cojocaru <rcojocaru@bitdefender.com>
> 
> The public API already has struct hvm_hw_cpu in
> xen/include/public/arch-x86/hvm/save.h
> 
> It might be better to reuse that rather than defining a new structure to
> contain a subset of the information.

While reinspecting the code to accommodate the critique - the reason why
I've not used struct hvm_hw_cpu back when I initially wrote the patch is
that sizeof(struct hvm_hw_cpu) is considerably larger that the size of
our custom struct. Using hvm_hw_cpu would have filled the mem_event ring
buffer fast, with each mem_event carrying an instance of it around.


Thanks,
Razvan Cojocaru