Btrfs: Add efficient dirty accounting to the extent_map tree

Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 6 insertions, 1 deletions

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index de0552532d23..eef4ab56b9ca 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -210,7 +210,7 @@ static int btree_writepages(struct address_space *mapping,
 {
         struct extent_map_tree *tree;
         tree = &BTRFS_I(mapping->host)->extent_tree;
-        if (wbc->sync_mode == WB_SYNC_NONE && current_is_pdflush()) {
+        if (wbc->sync_mode == WB_SYNC_NONE) {
                 u64 num_dirty;
                 u64 start = 0;
                 unsigned long thresh = 96 * 1024 * 1024;
@@ -218,6 +218,11 @@ static int btree_writepages(struct address_space *mapping,
                 if (wbc->for_kupdate)
                         return 0;
 
+                if (current_is_pdflush()) {
+                        thresh = 96 * 1024 * 1024;
+                } else {
+                        thresh = 8 * 1024 * 1024;
+                }
                 num_dirty = count_range_bits(tree, &start, thresh, EXTENT_DIRTY);
                 if (num_dirty < thresh) {
                         return 0;