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Date:   Wed, 10 Aug 2022 08:14:06 +0300
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Subject: Re: [PATCH v1 1/2] Enable balloon drivers to report inflated memory
To:     Muchun Song <muchun.song@linux.dev>
Cc:     Jonathan Corbet <corbet@lwn.net>,
        Andrew Morton <akpm@linux-foundation.org>, kernel@openvz.org,
        David Hildenbrand <david@redhat.com>,
        Wei Liu <wei.liu@kernel.org>, Nadav Amit <namit@vmware.com>,
        linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        linux-doc@vger.kernel.org, linux-mm@kvack.org
References: <7bfac48d-2e50-641b-6523-662ea4df0240@virtuozzo.com>
 <20220809094933.2203087-1-alexander.atanasov@virtuozzo.com>
 <5EFFFB23-9F73-4F07-B6FF-3BD05976D427@linux.dev>
From:   Alexander Atanasov <alexander.atanasov@virtuozzo.com>
In-Reply-To: <5EFFFB23-9F73-4F07-B6FF-3BD05976D427@linux.dev>
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Hello,

On 10.08.22 6:05, Muchun Song wrote:
> 
> 
>> On Aug 9, 2022, at 17:49, Alexander Atanasov <alexander.atanasov@virtuozzo.com> wrote:
>>
>> Display reported in /proc/meminfo as:
> 
> Hi,
> 
> I am not sure if this is a right place (meminfo) to put this statistic in since
> it is the accounting from a specific driver. IIUC, this driver is only installed
> in a VM, then this accounting will always be zero if this driver is not installed.
> Is this possible to put it in a driver-specific sysfs file (maybe it is better)?
> Just some thoughts from me.

Yes, it is only used if run under hypervisor but it is under a config 
option for that reason.

There are several balloon drivers that will use it, not only one driver 
- virtio, VMWare, HyperV, XEN and possibly others. I made one as an 
example. Initially i worked on a patches for debugfs but discussion lead 
to put it into a centralized place.

-- 
Regards,
Alexander Atanasov