[PATCH 3.2 105/140] dm thin metadata: introduce THIN_MAX_CONCURRENT_LOCKS

Ben Hutchings
2018-02-28T17:35:15Z

From: Joe Thornber <ejt@redhat.com>

commit 8c971178a788c70e8d6db5c3a813de1a1f54e5b7 upstream.

Introduce THIN_MAX_CONCURRENT_LOCKS into dm-thin-metadata to
give a name to an otherwise "magic" number.

Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
drivers/md/dm-thin-metadata.c | 14 ++++++++------
1 file changed, 8 insertions(+), 6 deletions(-)

--- a/drivers/md/dm-thin-metadata.c
+++ b/drivers/md/dm-thin-metadata.c
@@ -80,6 +80,12 @@
#define THIN_METADATA_CACHE_SIZE 64
#define SECTOR_TO_BLOCK_SHIFT 3

+/*
+ * 3 for btree insert +
+ * 2 for btree lookup used within space map
+ */
+#define THIN_MAX_CONCURRENT_LOCKS 5
+
/* This should be plenty */
#define SPACE_MAP_ROOT_SIZE 128

@@ -669,13 +675,9 @@ struct dm_pool_metadata *dm_pool_metadat
return ERR_PTR(-ENOMEM);
}

- /*
- * Max hex locks:
- * 3 for btree insert +
- * 2 for btree lookup used within space map
- */
bm = dm_block_manager_create(bdev, THIN_METADATA_BLOCK_SIZE,
- THIN_METADATA_CACHE_SIZE, 5);
+ THIN_METADATA_CACHE_SIZE,
+ THIN_MAX_CONCURRENT_LOCKS);
if (!bm) {
DMERR("could not create block manager");
kfree(pmd);