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/file.c b/fs/f2fs/file.c
index e755ee5..a9474cd 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -111,6 +111,7 @@
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 @@
/* 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 @@
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 @@
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;
}