Btrfs: cleanup for btrfs_btree_balance_dirty

- 'nr' is no more used.
- btrfs_btree_balance_dirty() and __btrfs_btree_balance_dirty() can share
  a bunch of code.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>

7 files changed, 34 insertions, 81 deletions

diff --git a/fs/btrfs/delayed-inode.c b/fs/btrfs/delayed-inode.c
index 0c6dca550ea1..34836036f01b 100644
--- a/fs/btrfs/delayed-inode.c
+++ b/fs/btrfs/delayed-inode.c
@@ -1257,7 +1257,6 @@ static void btrfs_async_run_delayed_node_done(struct btrfs_work *work)
         struct btrfs_delayed_node *delayed_node = NULL;
         struct btrfs_root *root;
         struct btrfs_block_rsv *block_rsv;
-        unsigned long nr = 0;
         int need_requeue = 0;
         int ret;
 
@@ -1318,11 +1317,9 @@ static void btrfs_async_run_delayed_node_done(struct btrfs_work *work)
                                            delayed_node);
         mutex_unlock(&delayed_node->mutex);
 
-        nr = trans->blocks_used;
-
         trans->block_rsv = block_rsv;
         btrfs_end_transaction_dmeta(trans, root);
-        __btrfs_btree_balance_dirty(root, nr);
+        btrfs_btree_balance_dirty_nodelay(root);
 free_path:
         btrfs_free_path(path);
 out:
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 07a2162cdd65..ff5d259ac275 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -3411,7 +3411,8 @@ void btrfs_mark_buffer_dirty(struct extent_buffer *buf)
         }
 }
 
-void btrfs_btree_balance_dirty(struct btrfs_root *root, unsigned long nr)
+static void __btrfs_btree_balance_dirty(struct btrfs_root *root,
+                                        int flush_delayed)
 {
         /*
          * looks as though older kernels can get into trouble with
@@ -3423,7 +3424,8 @@ void btrfs_btree_balance_dirty(struct btrfs_root *root, unsigned long nr)
         if (current->flags & PF_MEMALLOC)
                 return;
 
-        btrfs_balance_delayed_items(root);
+        if (flush_delayed)
+                btrfs_balance_delayed_items(root);
 
         num_dirty = root->fs_info->dirty_metadata_bytes;
 
@@ -3434,25 +3436,14 @@ void btrfs_btree_balance_dirty(struct btrfs_root *root, unsigned long nr)
         return;
 }
 
-void __btrfs_btree_balance_dirty(struct btrfs_root *root, unsigned long nr)
+void btrfs_btree_balance_dirty(struct btrfs_root *root)
 {
-        /*
-         * looks as though older kernels can get into trouble with
-         * this code, they end up stuck in balance_dirty_pages forever
-         */
-        u64 num_dirty;
-        unsigned long thresh = 32 * 1024 * 1024;
-
-        if (current->flags & PF_MEMALLOC)
-                return;
-
-        num_dirty = root->fs_info->dirty_metadata_bytes;
+        __btrfs_btree_balance_dirty(root, 1);
+}
 
-        if (num_dirty > thresh) {
-                balance_dirty_pages_ratelimited_nr(
-                                   root->fs_info->btree_inode->i_mapping, 1);
-        }
-        return;
+void btrfs_btree_balance_dirty_nodelay(struct btrfs_root *root)
+{
+        __btrfs_btree_balance_dirty(root, 0);
 }
 
 int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid)
diff --git a/fs/btrfs/disk-io.h b/fs/btrfs/disk-io.h
index 2025a9132c16..305c33efb0e3 100644
--- a/fs/btrfs/disk-io.h
+++ b/fs/btrfs/disk-io.h
@@ -62,8 +62,8 @@ struct btrfs_root *btrfs_read_fs_root_no_radix(struct btrfs_root *tree_root,
 struct btrfs_root *btrfs_read_fs_root_no_name(struct btrfs_fs_info *fs_info,
                                               struct btrfs_key *location);
 int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info);
-void btrfs_btree_balance_dirty(struct btrfs_root *root, unsigned long nr);
-void __btrfs_btree_balance_dirty(struct btrfs_root *root, unsigned long nr);
+void btrfs_btree_balance_dirty(struct btrfs_root *root);
+void btrfs_btree_balance_dirty_nodelay(struct btrfs_root *root);
 void btrfs_free_fs_root(struct btrfs_fs_info *fs_info, struct btrfs_root *root);
 void btrfs_mark_buffer_dirty(struct extent_buffer *buf);
 int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid,
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 883cf826cf25..bd7f1b01e051 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -1349,7 +1349,7 @@ static noinline ssize_t __btrfs_buffered_write(struct file *file,
                 balance_dirty_pages_ratelimited_nr(inode->i_mapping,
                                                    dirty_pages);
                 if (dirty_pages < (root->leafsize >> PAGE_CACHE_SHIFT) + 1)
-                        btrfs_btree_balance_dirty(root, 1);
+                        btrfs_btree_balance_dirty(root);
 
                 pos += copied;
                 num_written += copied;
@@ -1803,7 +1803,6 @@ static int btrfs_punch_hole(struct inode *inode, loff_t offset, loff_t len)
         u64 cur_offset = lockstart;
         u64 min_size = btrfs_calc_trunc_metadata_size(root, 1);
         u64 drop_end;
-        unsigned long nr;
         int ret = 0;
         int err = 0;
         bool same_page = (offset >> PAGE_CACHE_SHIFT) ==
@@ -1931,9 +1930,8 @@ static int btrfs_punch_hole(struct inode *inode, loff_t offset, loff_t len)
                         break;
                 }
 
-                nr = trans->blocks_used;
                 btrfs_end_transaction(trans, root);
-                btrfs_btree_balance_dirty(root, nr);
+                btrfs_btree_balance_dirty(root);
 
                 trans = btrfs_start_transaction(root, 3);
                 if (IS_ERR(trans)) {
@@ -1969,9 +1967,8 @@ out_trans:
 
         trans->block_rsv = &root->fs_info->trans_block_rsv;
         ret = btrfs_update_inode(trans, root, inode);
-        nr = trans->blocks_used;
         btrfs_end_transaction(trans, root);
-        btrfs_btree_balance_dirty(root, nr);
+        btrfs_btree_balance_dirty(root);
 out_free:
         btrfs_free_path(path);
         btrfs_free_block_rsv(root, rsv);
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index e8733fab2739..aabf747d056e 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -3091,7 +3091,6 @@ static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
         struct btrfs_trans_handle *trans;
         struct inode *inode = dentry->d_inode;
         int ret;
-        unsigned long nr = 0;
 
         trans = __unlink_start_trans(dir, dentry);
         if (IS_ERR(trans))
@@ -3111,9 +3110,8 @@ static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
         }
 
 out:
-        nr = trans->blocks_used;
         __unlink_end_trans(trans, root);
-        btrfs_btree_balance_dirty(root, nr);
+        btrfs_btree_balance_dirty(root);
         return ret;
 }
 
@@ -3203,7 +3201,6 @@ static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
         int err = 0;
         struct btrfs_root *root = BTRFS_I(dir)->root;
         struct btrfs_trans_handle *trans;
-        unsigned long nr = 0;
 
         if (inode->i_size > BTRFS_EMPTY_DIR_SIZE)
                 return -ENOTEMPTY;
@@ -3232,9 +3229,8 @@ static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
         if (!err)
                 btrfs_i_size_write(inode, 0);
 out:
-        nr = trans->blocks_used;
         __unlink_end_trans(trans, root);
-        btrfs_btree_balance_dirty(root, nr);
+        btrfs_btree_balance_dirty(root);
 
         return err;
 }
@@ -3800,7 +3796,6 @@ void btrfs_evict_inode(struct inode *inode)
         struct btrfs_root *root = BTRFS_I(inode)->root;
         struct btrfs_block_rsv *rsv, *global_rsv;
         u64 min_size = btrfs_calc_trunc_metadata_size(root, 1);
-        unsigned long nr;
         int ret;
 
         trace_btrfs_inode_evict(inode);
@@ -3882,10 +3877,9 @@ void btrfs_evict_inode(struct inode *inode)
                 ret = btrfs_update_inode(trans, root, inode);
                 BUG_ON(ret);
 
-                nr = trans->blocks_used;
                 btrfs_end_transaction(trans, root);
                 trans = NULL;
-                btrfs_btree_balance_dirty(root, nr);
+                btrfs_btree_balance_dirty(root);
         }
 
         btrfs_free_block_rsv(root, rsv);
@@ -3901,9 +3895,8 @@ void btrfs_evict_inode(struct inode *inode)
               root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID))
                 btrfs_return_ino(root, btrfs_ino(inode));
 
-        nr = trans->blocks_used;
         btrfs_end_transaction(trans, root);
-        btrfs_btree_balance_dirty(root, nr);
+        btrfs_btree_balance_dirty(root);
 no_delete:
         clear_inode(inode);
         return;
@@ -4915,7 +4908,6 @@ static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
         int err;
         int drop_inode = 0;
         u64 objectid;
-        unsigned long nr = 0;
         u64 index = 0;
 
         if (!new_valid_dev(rdev))
@@ -4965,9 +4957,8 @@ static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
                 d_instantiate(dentry, inode);
         }
 out_unlock:
-        nr = trans->blocks_used;
         btrfs_end_transaction(trans, root);
-        btrfs_btree_balance_dirty(root, nr);
+        btrfs_btree_balance_dirty(root);
         if (drop_inode) {
                 inode_dec_link_count(inode);
                 iput(inode);
@@ -4983,7 +4974,6 @@ static int btrfs_create(struct inode *dir, struct dentry *dentry,
         struct inode *inode = NULL;
         int drop_inode = 0;
         int err;
-        unsigned long nr = 0;
         u64 objectid;
         u64 index = 0;
 
@@ -5033,13 +5023,12 @@ static int btrfs_create(struct inode *dir, struct dentry *dentry,
                 d_instantiate(dentry, inode);
         }
 out_unlock:
-        nr = trans->blocks_used;
         btrfs_end_transaction(trans, root);
         if (drop_inode) {
                 inode_dec_link_count(inode);
                 iput(inode);
         }
-        btrfs_btree_balance_dirty(root, nr);
+        btrfs_btree_balance_dirty(root);
         return err;
 }
 
@@ -5050,7 +5039,6 @@ static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
         struct btrfs_root *root = BTRFS_I(dir)->root;
         struct inode *inode = old_dentry->d_inode;
         u64 index;
-        unsigned long nr = 0;
         int err;
         int drop_inode = 0;
 
@@ -5094,14 +5082,13 @@ static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
                 btrfs_log_new_name(trans, inode, NULL, parent);
         }
 
-        nr = trans->blocks_used;
         btrfs_end_transaction(trans, root);
 fail:
         if (drop_inode) {
                 inode_dec_link_count(inode);
                 iput(inode);
         }
-        btrfs_btree_balance_dirty(root, nr);
+        btrfs_btree_balance_dirty(root);
         return err;
 }
 
@@ -5114,7 +5101,6 @@ static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
         int drop_on_err = 0;
         u64 objectid = 0;
         u64 index = 0;
-        unsigned long nr = 1;
 
         /*
          * 2 items for inode and ref
@@ -5160,11 +5146,10 @@ static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
         drop_on_err = 0;
 
 out_fail:
-        nr = trans->blocks_used;
         btrfs_end_transaction(trans, root);
         if (drop_on_err)
                 iput(inode);
-        btrfs_btree_balance_dirty(root, nr);
+        btrfs_btree_balance_dirty(root);
         return err;
 }
 
@@ -6872,7 +6857,6 @@ static int btrfs_truncate(struct inode *inode)
         int ret;
         int err = 0;
         struct btrfs_trans_handle *trans;
-        unsigned long nr;
         u64 mask = root->sectorsize - 1;
         u64 min_size = btrfs_calc_trunc_metadata_size(root, 1);
 
@@ -6995,9 +6979,8 @@ static int btrfs_truncate(struct inode *inode)
                         break;
                 }
 
-                nr = trans->blocks_used;
                 btrfs_end_transaction(trans, root);
-                btrfs_btree_balance_dirty(root, nr);
+                btrfs_btree_balance_dirty(root);
 
                 trans = btrfs_start_transaction(root, 2);
                 if (IS_ERR(trans)) {
@@ -7031,9 +7014,8 @@ static int btrfs_truncate(struct inode *inode)
                 if (ret && !err)
                         err = ret;
 
-                nr = trans->blocks_used;
                 ret = btrfs_end_transaction(trans, root);
-                btrfs_btree_balance_dirty(root, nr);
+                btrfs_btree_balance_dirty(root);
         }
 
 out:
@@ -7594,7 +7576,6 @@ static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
         unsigned long ptr;
         struct btrfs_file_extent_item *ei;
         struct extent_buffer *leaf;
-        unsigned long nr = 0;
 
         name_len = strlen(symname) + 1;
         if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(root))
@@ -7692,13 +7673,12 @@ static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
 out_unlock:
         if (!err)
                 d_instantiate(dentry, inode);
-        nr = trans->blocks_used;
         btrfs_end_transaction(trans, root);
         if (drop_inode) {
                 inode_dec_link_count(inode);
                 iput(inode);
         }
-        btrfs_btree_balance_dirty(root, nr);
+        btrfs_btree_balance_dirty(root);
         return err;
 }
 
diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index 270f24ffe1be..300e09ac3659 100644
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -2025,7 +2025,6 @@ static noinline_for_stack int merge_reloc_root(struct reloc_control *rc,
         struct btrfs_root_item *root_item;
         struct btrfs_path *path;
         struct extent_buffer *leaf;
-        unsigned long nr;
         int level;
         int max_level;
         int replaced = 0;
@@ -2126,10 +2125,9 @@ static noinline_for_stack int merge_reloc_root(struct reloc_control *rc,
                                path->slots[level]);
                 root_item->drop_level = level;
 
-                nr = trans->blocks_used;
                 btrfs_end_transaction_throttle(trans, root);
 
-                btrfs_btree_balance_dirty(root, nr);
+                btrfs_btree_balance_dirty(root);
 
                 if (replaced && rc->stage == UPDATE_DATA_PTRS)
                         invalidate_extent_cache(root, &key, &next_key);
@@ -2156,10 +2154,9 @@ out:
                 btrfs_update_reloc_root(trans, root);
         }
 
-        nr = trans->blocks_used;
         btrfs_end_transaction_throttle(trans, root);
 
-        btrfs_btree_balance_dirty(root, nr);
+        btrfs_btree_balance_dirty(root);
 
         if (replaced && rc->stage == UPDATE_DATA_PTRS)
                 invalidate_extent_cache(root, &key, &next_key);
@@ -3262,7 +3259,6 @@ static int delete_block_group_cache(struct btrfs_fs_info *fs_info,
         struct btrfs_path *path;
         struct btrfs_root *root = fs_info->tree_root;
         struct btrfs_trans_handle *trans;
-        unsigned long nr;
         int ret = 0;
 
         if (inode)
@@ -3296,9 +3292,8 @@ truncate:
         ret = btrfs_truncate_free_space_cache(root, trans, path, inode);
 
         btrfs_free_path(path);
-        nr = trans->blocks_used;
         btrfs_end_transaction(trans, root);
-        btrfs_btree_balance_dirty(root, nr);
+        btrfs_btree_balance_dirty(root);
 out:
         iput(inode);
         return ret;
@@ -3715,7 +3710,6 @@ static noinline_for_stack int relocate_block_group(struct reloc_control *rc)
         struct btrfs_trans_handle *trans = NULL;
         struct btrfs_path *path;
         struct btrfs_extent_item *ei;
-        unsigned long nr;
         u64 flags;
         u32 item_size;
         int ret;
@@ -3832,9 +3826,8 @@ restart:
                         ret = btrfs_commit_transaction(trans, rc->extent_root);
                         BUG_ON(ret);
                 } else {
-                        nr = trans->blocks_used;
                         btrfs_end_transaction_throttle(trans, rc->extent_root);
-                        btrfs_btree_balance_dirty(rc->extent_root, nr);
+                        btrfs_btree_balance_dirty(rc->extent_root);
                 }
                 trans = NULL;
 
@@ -3864,9 +3857,8 @@ restart:
                           GFP_NOFS);
 
         if (trans) {
-                nr = trans->blocks_used;
                 btrfs_end_transaction_throttle(trans, rc->extent_root);
-                btrfs_btree_balance_dirty(rc->extent_root, nr);
+                btrfs_btree_balance_dirty(rc->extent_root);
         }
 
         if (!err) {
@@ -3945,7 +3937,6 @@ struct inode *create_reloc_inode(struct btrfs_fs_info *fs_info,
         struct btrfs_trans_handle *trans;
         struct btrfs_root *root;
         struct btrfs_key key;
-        unsigned long nr;
         u64 objectid = BTRFS_FIRST_FREE_OBJECTID;
         int err = 0;
 
@@ -3973,9 +3964,8 @@ struct inode *create_reloc_inode(struct btrfs_fs_info *fs_info,
 
         err = btrfs_orphan_add(trans, inode);
 out:
-        nr = trans->blocks_used;
         btrfs_end_transaction(trans, root);
-        btrfs_btree_balance_dirty(root, nr);
+        btrfs_btree_balance_dirty(root);
         if (err) {
                 if (inode)
                         iput(inode);
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index f21f39f0b1a1..7b297354e738 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -952,7 +952,6 @@ int btrfs_defrag_root(struct btrfs_root *root, int cacheonly)
         struct btrfs_fs_info *info = root->fs_info;
         struct btrfs_trans_handle *trans;
         int ret;
-        unsigned long nr;
 
         if (xchg(&root->defrag_running, 1))
                 return 0;
@@ -964,9 +963,8 @@ int btrfs_defrag_root(struct btrfs_root *root, int cacheonly)
 
                 ret = btrfs_defrag_leaves(trans, root, cacheonly);
 
-                nr = trans->blocks_used;
                 btrfs_end_transaction(trans, root);
-                btrfs_btree_balance_dirty(info->tree_root, nr);
+                btrfs_btree_balance_dirty(info->tree_root);
                 cond_resched();
 
                 if (btrfs_fs_closing(root->fs_info) || ret != -EAGAIN)