From: Joe Thornber Date: Wed, 28 Mar 2012 17:41:27 +0000 (+0100) Subject: dm persistent data: remove space map ref_count entries if redundant X-Git-Tag: v3.4-rc1~68^2~8 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=71fd5ae25d88841c08d5bbea90c0f0a12ca05509;p=pandora-kernel.git dm persistent data: remove space map ref_count entries if redundant Save space by removing entries from the space map ref_count tree if they're no longer needed. Ref counts are stored in two places: a bitmap if the ref_count is below 3, or a btree of 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. Signed-off-by: Joe Thornber Signed-off-by: Mike Snitzer Signed-off-by: Alasdair G Kergon --- Reading git-diff-tree failed