summaryrefslogtreecommitdiffstats
path: root/fs
diff options
context:
space:
mode:
authorJosef Bacik <josef@redhat.com>2011-01-24 21:43:19 +0000
committerChris Mason <chris.mason@oracle.com>2011-01-28 16:40:37 -0500
commite9e22899de661af94cb9995885fd04e4c738838b (patch)
tree3932040f0c5416e6ecbf508fa5d99b50eefbbc18 /fs
parentdedefd7215d3ec451291ca393e5c8e4c1882c8c6 (diff)
downloadblackbird-op-linux-e9e22899de661af94cb9995885fd04e4c738838b.tar.gz
blackbird-op-linux-e9e22899de661af94cb9995885fd04e4c738838b.zip
Btrfs: do not release more reserved bytes to the global_block_rsv than we need
When we do btrfs_block_rsv_release, if global_block_rsv is not full we will release all the extra bytes to global_block_rsv, even if it's only a little short of the amount of space that we need to reserve. This causes us to starve ourselves of reservable space during the transaction which will force us to shrink delalloc bytes and commit the transaction more often than we should. So instead just add the amount of bytes we need to add to the global reserve so reserved == size, and then add the rest back into the space_info for general use. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
Diffstat (limited to 'fs')
-rw-r--r--fs/btrfs/extent-tree.c16
1 files changed, 14 insertions, 2 deletions
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 98ee139885cc..7af618dcf2c0 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -3589,8 +3589,20 @@ void block_rsv_release_bytes(struct btrfs_block_rsv *block_rsv,
if (num_bytes > 0) {
if (dest) {
- block_rsv_add_bytes(dest, num_bytes, 0);
- } else {
+ spin_lock(&dest->lock);
+ if (!dest->full) {
+ u64 bytes_to_add;
+
+ bytes_to_add = dest->size - dest->reserved;
+ bytes_to_add = min(num_bytes, bytes_to_add);
+ dest->reserved += bytes_to_add;
+ if (dest->reserved >= dest->size)
+ dest->full = 1;
+ num_bytes -= bytes_to_add;
+ }
+ spin_unlock(&dest->lock);
+ }
+ if (num_bytes) {
spin_lock(&space_info->lock);
space_info->bytes_reserved -= num_bytes;
spin_unlock(&space_info->lock);
OpenPOWER on IntegriCloud