[RFC 2/5] virtio_balloon: update the NR_BALLOON_PAGES state
From: Nico Pache
Date: Tue Mar 11 2025 - 20:08:21 EST
Update the NR_BALLOON_PAGES counter when pages are added to or
removed from the virtio balloon.
Signed-off-by: Nico Pache <npache@xxxxxxxxxx>
---
drivers/virtio/virtio_balloon.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c
index 89da052f4f68..406414dbb477 100644
--- a/drivers/virtio/virtio_balloon.c
+++ b/drivers/virtio/virtio_balloon.c
@@ -274,6 +274,8 @@ static unsigned int fill_balloon(struct virtio_balloon *vb, size_t num)
set_page_pfns(vb, vb->pfns + vb->num_pfns, page);
vb->num_pages += VIRTIO_BALLOON_PAGES_PER_PAGE;
+ mod_node_page_state(page_pgdat(page), NR_BALLOON_PAGES,
+ VIRTIO_BALLOON_PAGES_PER_PAGE);
if (!virtio_has_feature(vb->vdev,
VIRTIO_BALLOON_F_DEFLATE_ON_OOM))
adjust_managed_page_count(page, -1);
@@ -324,6 +326,8 @@ static unsigned int leak_balloon(struct virtio_balloon *vb, size_t num)
set_page_pfns(vb, vb->pfns + vb->num_pfns, page);
list_add(&page->lru, &pages);
vb->num_pages -= VIRTIO_BALLOON_PAGES_PER_PAGE;
+ mod_node_page_state(page_pgdat(page), NR_BALLOON_PAGES,
+ -VIRTIO_BALLOON_PAGES_PER_PAGE);
}
num_freed_pages = vb->num_pfns;
--
2.48.1