Ref counts are stored in two places: a bitmap if the ref_count is
below 3, or a btreeof uint32_t if 3 or above.
When a ref_count that was above 3 drops below we can remove it from
the tree and save some metadata space. This removal was commented out
before because I was unsure why this was causing under populated btree
nodes. Earlier patches have fixed this issue.
---
drivers/md/persistent-data/dm-space-map-common.c | 3 ---
1 files changed, 0 insertions(+), 3 deletions(-)
diff --git a/drivers/md/persistent-data/dm-space-map-common.c b/drivers/md/persistent-data/dm-space-map-common.c
index df2494c..ff3beed 100644
--- a/drivers/md/persistent-data/dm-space-map-common.c
+++ b/drivers/md/persistent-data/dm-space-map-common.c
@@ -405,8 +405,6 @@ int sm_ll_insert(struct ll_disk *ll, dm_block_t b,
if (r < 0)
return r;
-#if 0
- /* FIXME: dm_btree_remove doesn't handle this yet */
if (old > 2) {
r = dm_btree_remove(&ll->ref_count_info,
ll->ref_count_root,
@@ -414,7 +412,6 @@ int sm_ll_insert(struct ll_disk *ll, dm_block_t b,
if (r)
return r;
}
-#endif
} else {
__le32 le_rc = cpu_to_le32(ref_count);
--
1.7.5.4
--
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