| Message ID | 20191205162247.19548.38842.stgit@localhost.localdomain (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | mm / virtio: Provide support for free page reporting | expand |
On Thu, Dec 05, 2019 at 08:22:47AM -0800, Alexander Duyck wrote: > From: Alexander Duyck <alexander.h.duyck@linux.intel.com> > > Currently the page poisoning setting wasn't being enabled unless free page > hinting was enabled. However we will need the page poisoning tracking logic > as well for free page reporting. As such pull it out and make it a separate > bit of config in the probe function. > > In addition we need to add support for the more recent init_on_free feature > which expects a behavior similar to page poisoning in that we expect the > page to be pre-zeroed. > > Reviewed-by: David Hildenbrand <david@redhat.com> > Signed-off-by: Alexander Duyck <alexander.h.duyck@linux.intel.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> > --- > drivers/virtio/virtio_balloon.c | 23 +++++++++++++++++------ > 1 file changed, 17 insertions(+), 6 deletions(-) > > diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c > index 15b7f1d8c334..252591bc7e01 100644 > --- a/drivers/virtio/virtio_balloon.c > +++ b/drivers/virtio/virtio_balloon.c > @@ -849,7 +849,6 @@ static int virtio_balloon_register_shrinker(struct virtio_balloon *vb) > static int virtballoon_probe(struct virtio_device *vdev) > { > struct virtio_balloon *vb; > - __u32 poison_val; > int err; > > if (!vdev->config->get) { > @@ -916,11 +915,20 @@ static int virtballoon_probe(struct virtio_device *vdev) > VIRTIO_BALLOON_CMD_ID_STOP); > spin_lock_init(&vb->free_page_list_lock); > INIT_LIST_HEAD(&vb->free_page_list); > - if (virtio_has_feature(vdev, VIRTIO_BALLOON_F_PAGE_POISON)) { > + } > + if (virtio_has_feature(vdev, VIRTIO_BALLOON_F_PAGE_POISON)) { > + /* Start with poison val of 0 representing general init */ > + __u32 poison_val = 0; > + > + /* > + * Let the hypervisor know that we are expecting a > + * specific value to be written back in balloon pages. > + */ > + if (!want_init_on_free()) > memset(&poison_val, PAGE_POISON, sizeof(poison_val)); > - virtio_cwrite(vb->vdev, struct virtio_balloon_config, > - poison_val, &poison_val); > - } > + > + virtio_cwrite(vb->vdev, struct virtio_balloon_config, > + poison_val, &poison_val); > } > /* > * We continue to use VIRTIO_BALLOON_F_DEFLATE_ON_OOM to decide if a > @@ -1021,7 +1029,10 @@ static int virtballoon_restore(struct virtio_device *vdev) > > static int virtballoon_validate(struct virtio_device *vdev) > { > - if (!page_poisoning_enabled()) > + /* Tell the host whether we care about poisoned pages. */ > + if (!want_init_on_free() && > + (IS_ENABLED(CONFIG_PAGE_POISONING_NO_SANITY) || > + !page_poisoning_enabled())) > __virtio_clear_bit(vdev, VIRTIO_BALLOON_F_PAGE_POISON); > > __virtio_clear_bit(vdev, VIRTIO_F_IOMMU_PLATFORM);
diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c index 15b7f1d8c334..252591bc7e01 100644 --- a/drivers/virtio/virtio_balloon.c +++ b/drivers/virtio/virtio_balloon.c @@ -849,7 +849,6 @@ static int virtio_balloon_register_shrinker(struct virtio_balloon *vb) static int virtballoon_probe(struct virtio_device *vdev) { struct virtio_balloon *vb; - __u32 poison_val; int err; if (!vdev->config->get) { @@ -916,11 +915,20 @@ static int virtballoon_probe(struct virtio_device *vdev) VIRTIO_BALLOON_CMD_ID_STOP); spin_lock_init(&vb->free_page_list_lock); INIT_LIST_HEAD(&vb->free_page_list); - if (virtio_has_feature(vdev, VIRTIO_BALLOON_F_PAGE_POISON)) { + } + if (virtio_has_feature(vdev, VIRTIO_BALLOON_F_PAGE_POISON)) { + /* Start with poison val of 0 representing general init */ + __u32 poison_val = 0; + + /* + * Let the hypervisor know that we are expecting a + * specific value to be written back in balloon pages. + */ + if (!want_init_on_free()) memset(&poison_val, PAGE_POISON, sizeof(poison_val)); - virtio_cwrite(vb->vdev, struct virtio_balloon_config, - poison_val, &poison_val); - } + + virtio_cwrite(vb->vdev, struct virtio_balloon_config, + poison_val, &poison_val); } /* * We continue to use VIRTIO_BALLOON_F_DEFLATE_ON_OOM to decide if a @@ -1021,7 +1029,10 @@ static int virtballoon_restore(struct virtio_device *vdev) static int virtballoon_validate(struct virtio_device *vdev) { - if (!page_poisoning_enabled()) + /* Tell the host whether we care about poisoned pages. */ + if (!want_init_on_free() && + (IS_ENABLED(CONFIG_PAGE_POISONING_NO_SANITY) || + !page_poisoning_enabled())) __virtio_clear_bit(vdev, VIRTIO_BALLOON_F_PAGE_POISON); __virtio_clear_bit(vdev, VIRTIO_F_IOMMU_PLATFORM);