[PATCH v1 2/2] virtio-balloon: improve update_balloon_size_func

Wei Wang
2019-01-03T05:31:02Z

There is no need to update the balloon actual register when there is no
ballooning request. This patch avoids update_balloon_size when diff is 0.

Signed-off-by: Wei Wang <wei.w.wang@intel.com>
---
drivers/virtio/virtio_balloon.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c
index 9a82a11..4884b85 100644
--- a/drivers/virtio/virtio_balloon.c
+++ b/drivers/virtio/virtio_balloon.c
@@ -435,9 +435,12 @@ static void update_balloon_size_func(struct work_struct *work)
update_balloon_size_work);
diff = towards_target(vb);

+ if (!diff)
+ return;
+
if (diff > 0)
diff -= fill_balloon(vb, diff);
- else if (diff < 0)
+ else
diff += leak_balloon(vb, -diff);
update_balloon_size(vb);

--
2.7.4