Re: [Qemu-devel] [PATCH 2/4] s390-cpu: ipi_states enhancements

["Jason J. Herne" <jjherne@linux.vnet.ibm.com>]

On 02/28/2014 11:30 AM, Andreas Färber wrote:
> Am 26.02.2014 18:18, schrieb Jason J. Herne:
>> From: "Jason J. Herne" <jjherne@us.ibm.com>
>>
>> Modify s390_cpu_addr2state to allow fetching state information for cpu addresses
>> above smp_cpus.  Hotplug requires this capability.
>>
>> Also add s390_cpu_set_state function to allow modification of ipi_state entries
>> during hotplug.
>>
>> Signed-off-by: Jason J. Herne <jjherne@us.ibm.com>
>
> This patch is *still* present despite your previous response that you
> incorporated my review comments. You are adding a custom s390x API here
> rather than reusing the generic QOM API as requested. I don't even read
> further in such cases - like I pointed out, a pure resend is not helping
> address review feedback!
>
> Andreas
>

Andreas,

My apologies, I am not trying to ruffle any feathers and I certainly 
have not intended to make you feel like I've ignored your review 
comments. I believe, if you look at patches 3 and 4 you will find that 
I've address the majority of your comments. I've even completed the work 
that adds the link property as you have suggested.

The reason the ipi_array still exists in my patch set is because I was 
under the impression that we needed it to still exist. This belief 
stemmed from a misunderstanding I had related to an earlier e-mail 
discussion. I apologize for getting that detail wrong. I had assumed we 
would make use of the link property when possible but still keep the 
array around too.

At this point, I only have one concern about removing the array. 
ipi_states is accessed from some high frequency code paths dealing with 
interrupt handling. I have not yet looked into it myself, but I trust I 
would find that retrieving the link property value would not 
significantly affect performance?

Thank you for taking the time to read this patch set. Please let me know 
if you have any more concerns. I'm happy to work with you to address them.

P.S. Sorry for taking so long to respond, I was away on vacation for a 
few days and I was not checking mail.

-- 
-- Jason J. Herne (jjherne@linux.vnet.ibm.com)