Btrfs: Use balance_dirty_pages_nr on btree blocks

btrfs_btree_balance_dirty is changed to pass the number of pages dirtied
for more accurate dirty throttling.  This lets the VM make better decisions
about when to force some writeback.

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

1 files changed, 10 insertions, 4 deletions

diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 29755593de65..087074db0bd5 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -18,6 +18,7 @@
 
 #include <linux/fs.h>
 #include <linux/sched.h>
+#include <linux/writeback.h>
 #include "ctree.h"
 #include "disk-io.h"
 #include "transaction.h"
@@ -340,6 +341,7 @@ int btrfs_defrag_root(struct btrfs_root *root, int cacheonly)
         struct btrfs_fs_info *info = root->fs_info;
         int ret;
         struct btrfs_trans_handle *trans;
+        unsigned long nr;
 
         if (root->defrag_running)
                 return 0;
@@ -348,10 +350,11 @@ int btrfs_defrag_root(struct btrfs_root *root, int cacheonly)
         while (1) {
                 root->defrag_running = 1;
                 ret = btrfs_defrag_leaves(trans, root, cacheonly);
+                nr = trans->blocks_used;
                 btrfs_end_transaction(trans, root);
                 mutex_unlock(&info->fs_mutex);
 
-                btrfs_btree_balance_dirty(root);
+                btrfs_btree_balance_dirty(info->tree_root, nr);
                 cond_resched();
 
                 mutex_lock(&info->fs_mutex);
@@ -398,6 +401,7 @@ static int drop_dirty_roots(struct btrfs_root *tree_root,
 {
         struct dirty_root *dirty;
         struct btrfs_trans_handle *trans;
+        unsigned long nr;
         u64 num_blocks;
         u64 blocks_used;
         int ret = 0;
@@ -426,11 +430,11 @@ static int drop_dirty_roots(struct btrfs_root *tree_root,
                                         &dirty->root->root_item);
                         if (err)
                                 ret = err;
+                        nr = trans->blocks_used;
                         ret = btrfs_end_transaction(trans, tree_root);
                         BUG_ON(ret);
                         mutex_unlock(&tree_root->fs_info->fs_mutex);
-
-                        btrfs_btree_balance_dirty(tree_root);
+                        btrfs_btree_balance_dirty(tree_root, nr);
                         schedule();
 
                         mutex_lock(&tree_root->fs_info->fs_mutex);
@@ -449,13 +453,15 @@ static int drop_dirty_roots(struct btrfs_root *tree_root,
                         BUG();
                         break;
                 }
+                nr = trans->blocks_used;
                 ret = btrfs_end_transaction(trans, tree_root);
                 BUG_ON(ret);
 
                 kfree(dirty->root);
                 kfree(dirty);
                 mutex_unlock(&tree_root->fs_info->fs_mutex);
-                btrfs_btree_balance_dirty(tree_root);
+
+                btrfs_btree_balance_dirty(tree_root, nr);
                 schedule();
         }
         return ret;