Commit d1df458c authored Dec 02, 2020 by Vitaly Kuznetsov Committed by Wei Liu Dec 13, 2020

hv_balloon: do adjust_managed_page_count() when ballooning/un-ballooning



Unlike virtio_balloon/virtio_mem/xen balloon drivers, Hyper-V balloon driver
does not adjust managed pages count when ballooning/un-ballooning and this leads
to incorrect stats being reported, e.g. unexpected 'free' output.

Note, the calculation in post_status() seems to remain correct: ballooned out
pages are never 'available' and we manually add dm->num_pages_ballooned to
'commited'.

Suggested-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20201202161245.2406143-3-vkuznets@redhat.com


Signed-off-by: Wei Liu <wei.liu@kernel.org>

parent 7f3f227b

drivers/hv/hv_balloon.c

+4 −1

Original line number	Diff line number	Diff line
		@@ -1198,6 +1198,7 @@ static void free_balloon_pages(struct hv_dynmem_device *dm,
		__ClearPageOffline(pg);
		__free_page(pg);
		dm->num_pages_ballooned--;
		adjust_managed_page_count(pg, 1);
		}
		}

		@@ -1238,8 +1239,10 @@ static unsigned int alloc_balloon_pages(struct hv_dynmem_device *dm,
		split_page(pg, get_order(alloc_unit << PAGE_SHIFT));

		/* mark all pages offline */
		for (j = 0; j < alloc_unit; j++)
		for (j = 0; j < alloc_unit; j++) {
		__SetPageOffline(pg + j);
		adjust_managed_page_count(pg + j, -1);
		}

		bl_resp->range_count++;
		bl_resp->range_array[i].finfo.start_page =

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