From mboxrd@z Thu Jan  1 00:00:00 1970
From: Kai Huang <kai.huang@linux.intel.com>
Subject: Re: [PATCH 09/10] log-dirty: Refine common code to
 support PML
Date: Fri, 10 Apr 2015 15:38:09 +0800
Message-ID: <55277DE1.6080301@linux.intel.com>
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To: Tim Deegan <tim@xen.org>
Cc: yang.z.zhang@intel.com, andrew.cooper3@citrix.com, kevin.tian@intel.com, jbeulich@suse.com, xen-devel@lists.xen.org
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On 04/09/2015 08:27 PM, Tim Deegan wrote:
> At 10:35 +0800 on 27 Mar (1427452553), Kai Huang wrote:
>> --- a/xen/arch/x86/mm/paging.c
>> +++ b/xen/arch/x86/mm/paging.c
>> @@ -411,7 +411,18 @@ static int paging_log_dirty_op(struct domain *d,
>>       int i4, i3, i2;
>>   
>>       if ( !resuming )
>> +    {
>>           domain_pause(d);
>> +
>> +        /*
>> +         * Only need to flush when not resuming, as domain was paused in
>> +         * resuming case therefore it's not possible to have any new dirty
>> +         * page.
>> +         */
>> +        if ( d->arch.paging.log_dirty.flush_cached_dirty )
>> +            d->arch.paging.log_dirty.flush_cached_dirty(d);
> I think there are too many layers of indirection here. :)  How about:
>   - don't add a flush_cached_dirty() function to the log_dirty ops.
>   - just call p2m_flush_hardware_cached_dirty(d) here.
>
> Would that work OK?
Thanks for pointing out.

Is it nature to call p2m layer functions in paging.c? If there's no 
restriction on it, calling p2m_flush_hardware_cached_dirty is more 
clear, and it should work.

Thanks,
-Kai
>
> Cheers,
>
> Tim.