f2fs: introduce fi->i_sem to protect fi's info

This patch introduces fi->i_sem to protect fi's info that includes xattr_ver,
pino, i_nlink.
This enables to remove i_mutex during f2fs_sync_file, resulting in performance
improvement when a number of fsync calls are triggered from many concurrent
threads.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>

diff --git a/fs/f2fs/dir.c b/fs/f2fs/dir.c
index 7c9b17c0367581e4e7253e602b4e8f2b54e9cb0d..972fd0ef230f9aff12f877a4f056980ad07757f3 100644 (file)
--- a/fs/f2fs/dir.c
+++ b/fs/f2fs/dir.c
@@ -493,6 +493,7 @@ start:
 add_dentry:
        f2fs_wait_on_page_writeback(dentry_page, DATA);
 
+       down_write(&F2FS_I(inode)->i_sem);
        page = init_inode_metadata(inode, dir, name);
        if (IS_ERR(page)) {
                err = PTR_ERR(page);
@@ -515,6 +516,8 @@ add_dentry:
 
        update_parent_metadata(dir, inode, current_depth);
 fail:
+       up_write(&F2FS_I(inode)->i_sem);
+
        if (is_inode_flag_set(F2FS_I(dir), FI_UPDATE_DIR)) {
                update_inode_page(dir);
                clear_inode_flag(F2FS_I(dir), FI_UPDATE_DIR);
@@ -559,6 +562,8 @@ void f2fs_delete_entry(struct f2fs_dir_entry *dentry, struct page *page,
        if (inode) {
                struct f2fs_sb_info *sbi = F2FS_SB(dir->i_sb);
 
+               down_write(&F2FS_I(inode)->i_sem);
+
                if (S_ISDIR(inode->i_mode)) {
                        drop_nlink(dir);
                        update_inode_page(dir);
@@ -569,6 +574,7 @@ void f2fs_delete_entry(struct f2fs_dir_entry *dentry, struct page *page,
                        drop_nlink(inode);
                        i_size_write(inode, 0);
                }
+               up_write(&F2FS_I(inode)->i_sem);
                update_inode_page(inode);
 
                if (inode->i_nlink == 0)

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 05c652493f04aa93fc2af5abda3b06a6d05e730c..469779ab1d772f128d0d308d4851c83d62fe9bff 100644 (file)
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -210,6 +210,7 @@ struct f2fs_inode_info {
 
        /* Use below internally in f2fs*/
        unsigned long flags;            /* use to pass per-file flags */
+       struct rw_semaphore i_sem;      /* protect fi info */
        atomic_t dirty_dents;           /* # of dirty dentry pages */
        f2fs_hash_t chash;              /* hash value of given file name */
        unsigned int clevel;            /* maximum level of given file name */

diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index e755ee57e042a081405c1d1b745e246004a4ba6b..a9474cd4e0db68a550a5e002ddf56e4abb856b0f 100644 (file)
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -111,6 +111,7 @@ static int get_parent_ino(struct inode *inode, nid_t *pino)
 int f2fs_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
 {
        struct inode *inode = file->f_mapping->host;
+       struct f2fs_inode_info *fi = F2FS_I(inode);
        struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
        int ret = 0;
        bool need_cp = false;
@@ -133,7 +134,7 @@ int f2fs_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
        /* guarantee free sections for fsync */
        f2fs_balance_fs(sbi);
 
-       mutex_lock(&inode->i_mutex);
+       down_read(&fi->i_sem);
 
        /*
         * Both of fdatasync() and fsync() are able to be recovered from
@@ -150,21 +151,27 @@ int f2fs_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
        else if (F2FS_I(inode)->xattr_ver == cur_cp_version(F2FS_CKPT(sbi)))
                need_cp = true;
 
+       up_read(&fi->i_sem);
+
        if (need_cp) {
                nid_t pino;
 
-               F2FS_I(inode)->xattr_ver = 0;
-
                /* all the dirty node pages should be flushed for POR */
                ret = f2fs_sync_fs(inode->i_sb, 1);
+
+               down_write(&fi->i_sem);
+               F2FS_I(inode)->xattr_ver = 0;
                if (file_wrong_pino(inode) && inode->i_nlink == 1 &&
                                        get_parent_ino(inode, &pino)) {
                        F2FS_I(inode)->i_pino = pino;
                        file_got_pino(inode);
+                       up_write(&fi->i_sem);
                        mark_inode_dirty_sync(inode);
                        ret = f2fs_write_inode(inode, NULL);
                        if (ret)
                                goto out;
+               } else {
+                       up_write(&fi->i_sem);
                }
        } else {
                /* if there is no written node page, write its inode page */
@@ -180,7 +187,6 @@ int f2fs_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
                ret = blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL, NULL);
        }
 out:
-       mutex_unlock(&inode->i_mutex);
        trace_f2fs_sync_file_exit(inode, need_cp, datasync, ret);
        return ret;
 }

diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c
index 397d459e97bf9f1ee2107c1079f02a282a47e5fa..0cea87437a609bafcdb61f07463c56c87492eb54 100644 (file)
--- a/fs/f2fs/namei.c
+++ b/fs/f2fs/namei.c
@@ -424,12 +424,17 @@ static int f2fs_rename(struct inode *old_dir, struct dentry *old_dentry,
                }
 
                f2fs_set_link(new_dir, new_entry, new_page, old_inode);
+               down_write(&F2FS_I(old_inode)->i_sem);
                F2FS_I(old_inode)->i_pino = new_dir->i_ino;
+               up_write(&F2FS_I(old_inode)->i_sem);
 
                new_inode->i_ctime = CURRENT_TIME;
+               down_write(&F2FS_I(new_inode)->i_sem);
                if (old_dir_entry)
                        drop_nlink(new_inode);
                drop_nlink(new_inode);
+               up_write(&F2FS_I(new_inode)->i_sem);
+
                mark_inode_dirty(new_inode);
 
                if (!new_inode->i_nlink)
@@ -459,7 +464,9 @@ static int f2fs_rename(struct inode *old_dir, struct dentry *old_dentry,
                if (old_dir != new_dir) {
                        f2fs_set_link(old_inode, old_dir_entry,
                                                old_dir_page, new_dir);
+                       down_write(&F2FS_I(old_inode)->i_sem);
                        F2FS_I(old_inode)->i_pino = new_dir->i_ino;
+                       up_write(&F2FS_I(old_inode)->i_sem);
                        update_inode_page(old_inode);
                } else {
                        kunmap(old_dir_page);

diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 34c47b2010bcef9fe6b1bf06fba1b8014689e886..89ea046c846db16f113801503becb29833656b42 100644 (file)
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -360,6 +360,7 @@ static struct inode *f2fs_alloc_inode(struct super_block *sb)
        fi->i_current_depth = 1;
        fi->i_advise = 0;
        rwlock_init(&fi->ext.ext_lock);
+       init_rwsem(&fi->i_sem);
 
        set_inode_flag(fi, FI_NEW_INODE);
 

diff --git a/fs/f2fs/xattr.c b/fs/f2fs/xattr.c
index 89d0422a91a88fea51ecf5935d31c2920545f8a6..84191307a670be0cdff09192f9485c7294ac1563 100644 (file)
--- a/fs/f2fs/xattr.c
+++ b/fs/f2fs/xattr.c
@@ -590,7 +590,10 @@ int f2fs_setxattr(struct inode *inode, int name_index, const char *name,
        f2fs_balance_fs(sbi);
 
        f2fs_lock_op(sbi);
+       /* protect xattr_ver */
+       down_write(&F2FS_I(inode)->i_sem);
        err = __f2fs_setxattr(inode, name_index, name, value, value_len, ipage);
+       up_write(&F2FS_I(inode)->i_sem);
        f2fs_unlock_op(sbi);
 
        return err;