Re: [Qemu-devel] [PATCH v2 1/1] virtio-balloon: include statistics of disk/file caches

[Jonathan Helman]

> On Feb 19, 2018, at 5:11 AM, Tomáš Golembiovský <address@hidden> wrote:
> 
> On Wed, 14 Feb 2018 00:07:53 +0200
> "Michael S. Tsirkin" <address@hidden> wrote:
> 
>> On Tue, Feb 13, 2018 at 12:29:39PM -0800, Jonathan Helman wrote:
>>> 
>>> 
>>> On 02/05/2018 04:08 AM, Tomáš Golembiovský wrote:  
>>>> ping
>>>> 
>>>> On Tue,  5 Dec 2017 13:14:46 +0100
>>>> Tomáš Golembiovský <address@hidden> wrote:
>>>> 
>>> 
>>> It would be good to include the corresponding upstream kernel change in the
>>> commit message. This would be similar to a previous change:
>>> https://lists.gnu.org/archive/html/qemu-devel/2016-02/msg05555.html  
>> 
>> good idea, but this has been merged by now.
> 
> Maybe next time, sorry.
> 
> 
>>>>> Signed-off-by: Tomáš Golembiovský <address@hidden>
>>>>> ---
>>>>>  hw/virtio/virtio-balloon.c                      | 1 +
>>>>>  include/standard-headers/linux/virtio_balloon.h | 3 ++-
>>>>>  2 files changed, 3 insertions(+), 1 deletion(-)
>>>>> 
>>>>> diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c
>>>>> index 37cde38982..8141326a51 100644
>>>>> --- a/hw/virtio/virtio-balloon.c
>>>>> +++ b/hw/virtio/virtio-balloon.c
>>>>> @@ -50,6 +50,7 @@ static const char *balloon_stat_names[] = {
>>>>>     [VIRTIO_BALLOON_S_MEMFREE] = "stat-free-memory",
>>>>>     [VIRTIO_BALLOON_S_MEMTOT] = "stat-total-memory",
>>>>>     [VIRTIO_BALLOON_S_AVAIL] = "stat-available-memory",
>>>>> +   [VIRTIO_BALLOON_S_CACHES] = "stat-disk-caches",
>>>>>     [VIRTIO_BALLOON_S_NR] = NULL
>>>>>  };
>>>>> diff --git a/include/standard-headers/linux/virtio_balloon.h 
>>>>> b/include/standard-headers/linux/virtio_balloon.h
>>>>> index 9d06ccd066..7b0a41b8fc 100644
>>>>> --- a/include/standard-headers/linux/virtio_balloon.h
>>>>> +++ b/include/standard-headers/linux/virtio_balloon.h
>>>>> @@ -52,7 +52,8 @@ struct virtio_balloon_config {
>>>>>  #define VIRTIO_BALLOON_S_MEMFREE  4   /* Total amount of free memory */
>>>>>  #define VIRTIO_BALLOON_S_MEMTOT   5   /* Total amount of memory */
>>>>>  #define VIRTIO_BALLOON_S_AVAIL    6   /* Available memory as in /proc */
>>>>> -#define VIRTIO_BALLOON_S_NR       7
>>>>> +#define VIRTIO_BALLOON_S_CACHES   7   /* Disk caches */  
>>> 
>>> I've been wondering, VIRTIO_BALLOON_S_AVAIL is not in the virtio spec (see
>>> Section 5.5.6.3). It seems like this header file needs to be in sync with
>>> the virtio spec in order to make this change.
>>> 
>>> I have a similar change to add a new statistic and was wondering this.  
>> 
>> Absolutely. Tomáš?
> 
> Sent. I also included description for the VIRTIO_BALLOON_S_AVAIL that
> was missing.
> 
> 
>>>>> +#define VIRTIO_BALLOON_S_NR       8
>>>>>  /*
>>>>>   * Memory statistics structure.
>>>>> -- 
>>>>> 2.15.1
>>>>> 
>>>> 
>>>> 
>>> 
>>> You need to add your new stat to the list of stats in
>>> docs/virtio-balloon-stats.txt.
>>> 
>>> Jon  
>> 
>> Can't hurt, I agree.
> 
> Sent.
> 

Awesome, thank you.

Do you also plan to make the commensurate changes in libvirt, or did I just 
miss the patch?

Jon

>    Tomas
> 
> -- 
> Tomáš Golembiovský <address@hidden>