f2fs: reduce region of f2fs_lock_op covered for better concurrency

In our rename process, region of f2fs_lock_op covered is too big as some of the
code like f2fs_empty_dir/f2fs_find_entry are not needed to protect by this lock.

So in the extreme case like doing checkpoint when we rename old inode to exist
inode in a large directory could cause lower concurrency.

Let's reduce the region of f2fs_lock_op to fix this.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

1 files changed, 8 insertions, 4 deletions

diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c
index 89b0bd9420cc..1b3cae03c24f 100644
--- a/fs/f2fs/namei.c
+++ b/fs/f2fs/namei.c
@@ -387,8 +387,6 @@ static int f2fs_rename(struct inode *old_dir, struct dentry *old_dentry,
                         goto out_old;
         }
 
-        f2fs_lock_op(sbi);
-
         if (new_inode) {
 
                 err = -ENOTEMPTY;
@@ -401,6 +399,8 @@ static int f2fs_rename(struct inode *old_dir, struct dentry *old_dentry,
                 if (!new_entry)
                         goto out_dir;
 
+                f2fs_lock_op(sbi);
+
                 err = acquire_orphan_inode(sbi);
                 if (err)
                         goto put_out_dir;
@@ -429,9 +429,13 @@ static int f2fs_rename(struct inode *old_dir, struct dentry *old_dentry,
                 update_inode_page(old_inode);
                 update_inode_page(new_inode);
         } else {
+                f2fs_lock_op(sbi);
+
                 err = f2fs_add_link(new_dentry, old_inode);
-                if (err)
+                if (err) {
+                        f2fs_unlock_op(sbi);
                         goto out_dir;
+                }
 
                 if (old_dir_entry) {
                         inc_nlink(new_dir);
@@ -466,6 +470,7 @@ static int f2fs_rename(struct inode *old_dir, struct dentry *old_dentry,
         return 0;
 
 put_out_dir:
+        f2fs_unlock_op(sbi);
         kunmap(new_page);
         f2fs_put_page(new_page, 0);
 out_dir:
@@ -473,7 +478,6 @@ out_dir:
                 kunmap(old_dir_page);
                 f2fs_put_page(old_dir_page, 0);
         }
-        f2fs_unlock_op(sbi);
 out_old:
         kunmap(old_page);
         f2fs_put_page(old_page, 0);