diff options
| author | Michael S. Tsirkin | 2019-11-19 05:25:24 -0500 |
|---|---|---|
| committer | Michael S. Tsirkin | 2019-12-11 08:14:07 -0500 |
| commit | 63b9b80e9f5b2c463d98d6e550e0d0e3ace66033 (patch) | |
| tree | cc7783bec788c6b87dc68d93654df3ab96f18ace | |
| parent | 2a946fa1c8bc26df03bacebb6811b656d5e0cf1c (diff) | |
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.c | 9 |
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; } |