[PATCH v2 4/4] xen: balloon: update the NR_BALLOON_PAGES state

[Nico Pache]

Update the NR_BALLOON_PAGES counter when pages are added to or
removed from the Xen balloon.

Signed-off-by: Nico Pache <npa...@redhat.com>
---
 drivers/xen/balloon.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/xen/balloon.c b/drivers/xen/balloon.c
index 163f7f1d70f1..65d4e7fa1eb8 100644
--- a/drivers/xen/balloon.c
+++ b/drivers/xen/balloon.c
@@ -157,6 +157,8 @@ static void balloon_append(struct page *page)
                list_add(&page->lru, &ballooned_pages);
                balloon_stats.balloon_low++;
        }
+       inc_node_page_state(page, NR_BALLOON_PAGES);
+
        wake_up(&balloon_wq);
 }
 
@@ -179,6 +181,8 @@ static struct page *balloon_retrieve(bool require_lowmem)
                balloon_stats.balloon_low--;
 
        __ClearPageOffline(page);
+       dec_node_page_state(page, NR_BALLOON_PAGES);
+
        return page;
 }
 
-- 
2.48.1