aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorMichael S. Tsirkin <mst@redhat.com>2019-11-19 05:25:24 -0500
committerMichael S. Tsirkin <mst@redhat.com>2019-12-11 08:14:07 -0500
commit63b9b80e9f5b2c463d98d6e550e0d0e3ace66033 (patch)
treecc7783bec788c6b87dc68d93654df3ab96f18ace
parent2a946fa1c8bc26df03bacebb6811b656d5e0cf1c (diff)
downloadlinux-stericsson-63b9b80e9f5b2c463d98d6e550e0d0e3ace66033.tar.gz
virtio_balloon: divide/multiply instead of shifts
We managed to get confused about the shift direction at least once. Let's switch to division/multiplcation instead. Add a number of pages macro for this purpose. We still keep the order macro around too since this is what alloc/free pages want. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Wei Wang <wei.w.wang@intel.com> Reviewed-by: David Hildenbrand <david@redhat.com>
-rw-r--r--drivers/virtio/virtio_balloon.c9
1 files changed, 5 insertions, 4 deletions
diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c
index 23119b3a71bd..93f995f6cf36 100644
--- a/drivers/virtio/virtio_balloon.c
+++ b/drivers/virtio/virtio_balloon.c
@@ -36,6 +36,7 @@
/* The size of a free page block in bytes */
#define VIRTIO_BALLOON_HINT_BLOCK_BYTES \
(1 << (VIRTIO_BALLOON_HINT_BLOCK_ORDER + PAGE_SHIFT))
+#define VIRTIO_BALLOON_HINT_BLOCK_PAGES (1 << VIRTIO_BALLOON_HINT_BLOCK_ORDER)
#ifdef CONFIG_BALLOON_COMPACTION
static struct vfsmount *balloon_mnt;
@@ -776,11 +777,11 @@ static unsigned long shrink_free_pages(struct virtio_balloon *vb,
unsigned long blocks_to_free, blocks_freed;
pages_to_free = round_up(pages_to_free,
- 1 << VIRTIO_BALLOON_HINT_BLOCK_ORDER);
- blocks_to_free = pages_to_free >> VIRTIO_BALLOON_HINT_BLOCK_ORDER;
+ VIRTIO_BALLOON_HINT_BLOCK_PAGES);
+ blocks_to_free = pages_to_free / VIRTIO_BALLOON_HINT_BLOCK_PAGES;
blocks_freed = return_free_pages_to_mm(vb, blocks_to_free);
- return blocks_freed << VIRTIO_BALLOON_HINT_BLOCK_ORDER;
+ return blocks_freed * VIRTIO_BALLOON_HINT_BLOCK_PAGES;
}
static unsigned long leak_balloon_pages(struct virtio_balloon *vb,
@@ -837,7 +838,7 @@ static unsigned long virtio_balloon_shrinker_count(struct shrinker *shrinker,
unsigned long count;
count = vb->num_pages / VIRTIO_BALLOON_PAGES_PER_PAGE;
- count += vb->num_free_page_blocks << VIRTIO_BALLOON_HINT_BLOCK_ORDER;
+ count += vb->num_free_page_blocks * VIRTIO_BALLOON_HINT_BLOCK_PAGES;
return count;
}