From mboxrd@z Thu Jan  1 00:00:00 1970
From: Kai Huang <kai.huang@linux.intel.com>
Subject: Re: [v2 10/11] log-dirty: refine common code to support
 PML
Date: Fri, 17 Apr 2015 10:46:34 +0800
Message-ID: <5530740A.1080002@linux.intel.com>
References: <1429081433-9600-1-git-send-email-kai.huang@linux.intel.com>	<1429081433-9600-11-git-send-email-kai.huang@linux.intel.com>
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To: Jan Beulich <JBeulich@suse.com>
Cc: andrew.cooper3@citrix.com, kevin.tian@intel.com, tim@xen.org, xen-devel@lists.xen.org
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On 04/16/2015 11:51 PM, Jan Beulich wrote:
>>>> On 15.04.15 at 09:03, <kai.huang@linux.intel.com> wrote:
>> @@ -190,9 +196,15 @@ static int hap_enable_log_dirty(struct domain *d, bool_t log_global)
>>       d->arch.paging.mode |= PG_log_dirty;
>>       paging_unlock(d);
>>   
>> +    /* enable hardware-assisted log-dirty if it is supported */
>> +    p2m_enable_hardware_log_dirty(d);
> I don't see that you would anywhere avoid setting up software
> log-dirty handling - is that on purpose? If so, is there really a
> win from adding PML?
>
>>       if ( log_global )
>>       {
>> -        /* set l1e entries of P2M table to be read-only. */
>> +        /*
>> +         * switch to log dirty mode, either by setting l1e entries of P2M table
>> +         * to be read-only, or via hardware-assisted log-dirty.
>> +         */
>>           p2m_change_entry_type_global(d, p2m_ram_rw, p2m_ram_logdirty);
> Or did I miss you changing the behavior of this anywhere (as the
> changed comment suggests)?
Both of your comments are done in patch 11.

And I think even without patch 11, there's no harm with this patch as 
p2m_enable_hardware_log_dirty will essentially do nothing and write 
protection will be used for log-dirty :)

Thanks,
-Kai
>
> Jan
>
>
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