From: Nico Pache <redacted> Sent: Friday, March 14, 2025 2:38 PM
quoted hunk ↗ jump to hunk
Update the NR_BALLOON_PAGES counter when pages are added to or
removed from the Hyper-V balloon.
Signed-off-by: Nico Pache <redacted>
---
drivers/hv/hv_balloon.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/hv/hv_balloon.c b/drivers/hv/hv_balloon.c
index fec2f18679e3..2b4080e51f97 100644
--- a/drivers/hv/hv_balloon.c
+++ b/drivers/hv/hv_balloon.c
@@ -1192,6 +1192,7 @@ static void free_balloon_pages(struct hv_dynmem_device *dm,
__ClearPageOffline(pg);
__free_page(pg);
dm->num_pages_ballooned--;
+ mod_node_page_state(page_pgdat(pg), NR_BALLOON_PAGES, -1);
adjust_managed_page_count(pg, 1);
}
}
@@ -1221,6 +1222,7 @@ static unsigned int alloc_balloon_pages(struct hv_dynmem_device *dm,
return i * alloc_unit;
dm->num_pages_ballooned += alloc_unit;
+ mod_node_page_state(page_pgdat(pg), NR_BALLOON_PAGES, alloc_unit);
/*
* If we allocatted 2M pages; split them so we
--
2.48.1
As is evident from the code, the hv_balloon driver already has accounting
for the number of pages that have been ballooned out of the VM. This
accounting and other details of the hv_balloon driver state is available in
/sys/kernel/debug/hv-balloon when CONFIG_DEBUGFS=y. But it seems OK
to also report the # of pages ballooned through /proc/meminfo, which
works even if CONFIG_DEBUGFS=n.
Reviewed-by: Michael Kelley <redacted>