Re: [PATCH V13 4/7] xen/arm: Data abort exception (R/W) mem_events.

[Julien Grall <julien.grall@linaro.org>]

On 12/03/15 15:19, Tamas K Lengyel wrote:
> 
>>  out:
> 
>         > +    if ( flush )
>         > +    {
>         > +        flush_tlb_domain(d);
>         > +        iommu_iotlb_flush(d, sgfn, egfn - sgfn);
>         > +    }
> 
>         Is moving the flush out of the loop an independent bug fix? If
>         so please
>         do in a separate commit with a rationale in the commit log. If it is
>         somehow related to the changes here then please mention it in this
>         commit log, since it's a bit subtle.
> 
> 
>     Right, it's not a bugfix and not required to be outside the loop, I
>     think I just moved it because it made sense to me to flush it only
>     once instead at every iteration. I'll place it back.
> 
> 
> Sorry, the flush wasn't actually part of the loop to begin with. I just
> moved it under the label out so that the TLB gets flushed when the
> memaccess setting hypercall gets preempted. I will just set a separate
> label for it before out so that the existing behavior is preserved but
> the tlb is still flushed when memaccess is preempted.

Even though today it's only require for memaccess, the code move would
benefit all others caller later. Mainly if we decide to support
preemption later...

Regards,

-- 
Julien Grall