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Message-ID: <0530d9d32a7316adee62e067cb0fb8048f97da84.camel@linux.intel.com>
Subject: Re: [PATCH v2 5/5] virtio-balloon: Add support for providing page
 hints to host
From:   Alexander Duyck <alexander.h.duyck@linux.intel.com>
To:     Nitesh Narayan Lal <nitesh@redhat.com>,
        Alexander Duyck <alexander.duyck@gmail.com>,
        kvm@vger.kernel.org, david@redhat.com, mst@redhat.com,
        dave.hansen@intel.com, linux-kernel@vger.kernel.org,
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Cc:     yang.zhang.wz@gmail.com, pagupta@redhat.com, riel@surriel.com,
        konrad.wilk@oracle.com, lcapitulino@redhat.com,
        wei.w.wang@intel.com, aarcange@redhat.com, pbonzini@redhat.com,
        dan.j.williams@intel.com
Date:   Thu, 25 Jul 2019 12:54:21 -0700
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On Thu, 2019-07-25 at 13:42 -0400, Nitesh Narayan Lal wrote:
> On 7/24/19 1:05 PM, Alexander Duyck wrote:
> > From: Alexander Duyck <alexander.h.duyck@linux.intel.com>
> > 
> > 

<snip>

> > @@ -924,12 +956,24 @@ static int virtballoon_probe(struct virtio_device *vdev)
> >  		if (err)
> >  			goto out_del_balloon_wq;
> >  	}
> > +
> > +	vb->ph_dev_info.react = virtballoon_page_hinting_react;
> > +	vb->ph_dev_info.capacity = VIRTIO_BALLOON_ARRAY_HINTS_MAX;
> > +	if (virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_HINTING)) {
> > +		err = page_hinting_startup(&vb->ph_dev_info);
> > +		if (err)
> > +			goto out_unregister_shrinker;
> > +	}
> Any reason why you have kept vb->ph_dev_info.react & vb->ph_dev_info.capacity
> initialization outside the feature check?

I just had them on the outside because it didn't really matter if I
initialized them or not if the feature was not present. So I just
defaulted to initializing them in all cases.

Since I will be updating capacity to be based on the size of the hinting
queue in the next patch set I will move capacity initialization inside of
the check.