RE: [f2fs-dev] [PATCH 2/4 v2] f2fs: avoid unnecessary f2fs_gc for dir operations

[Chao Yu <chao2.yu@samsung.com>]

Hi Jaegeuk,

> -----Original Message-----
> From: Jaegeuk Kim [mailto:jaegeuk@kernel.org]
> Sent: Thursday, December 24, 2015 2:55 AM
> To: Chao Yu
> Cc: linux-kernel@vger.kernel.org; linux-fsdevel@vger.kernel.org;
> linux-f2fs-devel@lists.sourceforge.net
> Subject: Re: [f2fs-dev] [PATCH 2/4 v2] f2fs: avoid unnecessary f2fs_gc for dir operations
> 
> Chang log from v1:
>  - add more cases
> 
> From 9fea6346f5dd2992525e853e27a4fe899d122379 Mon Sep 17 00:00:00 2001
> From: Jaegeuk Kim <jaegeuk@kernel.org>
> Date: Tue, 22 Dec 2015 11:56:08 -0800
> Subject: [PATCH] f2fs: avoid unnecessary f2fs_gc for dir operations
> 
> The f2fs_balance_fs doesn't need to cover f2fs_new_inode or f2fs_find_entry
> works.
> 
> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
> ---
>  fs/f2fs/namei.c | 34 ++++++++++++++++++----------------
>  1 file changed, 18 insertions(+), 16 deletions(-)
> 
> diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c
> index 2c32110..e4588f7 100644
> --- a/fs/f2fs/namei.c
> +++ b/fs/f2fs/namei.c
> @@ -128,8 +128,6 @@ static int f2fs_create(struct inode *dir, struct dentry *dentry, umode_t
> mode,
>  	nid_t ino = 0;
>  	int err;
> 
> -	f2fs_balance_fs(sbi);
> -
>  	inode = f2fs_new_inode(dir, mode);
>  	if (IS_ERR(inode))
>  		return PTR_ERR(inode);
> @@ -142,6 +140,8 @@ static int f2fs_create(struct inode *dir, struct dentry *dentry, umode_t
> mode,
>  	inode->i_mapping->a_ops = &f2fs_dblock_aops;
>  	ino = inode->i_ino;
> 
> +	f2fs_balance_fs(sbi);
> +
>  	f2fs_lock_op(sbi);
>  	err = f2fs_add_link(dentry, inode);
>  	if (err)
> @@ -288,12 +288,13 @@ static int f2fs_unlink(struct inode *dir, struct dentry *dentry)
>  	int err = -ENOENT;
> 
>  	trace_f2fs_unlink_enter(dir, dentry);
> -	f2fs_balance_fs(sbi);
> 
>  	de = f2fs_find_entry(dir, &dentry->d_name, &page);
>  	if (!de)
>  		goto fail;
> 
> +	f2fs_balance_fs(sbi);
> +
>  	f2fs_lock_op(sbi);
>  	err = acquire_orphan_inode(sbi);
>  	if (err) {
> @@ -341,8 +342,6 @@ static int f2fs_symlink(struct inode *dir, struct dentry *dentry,
>  	if (len > dir->i_sb->s_blocksize)
>  		return -ENAMETOOLONG;
> 
> -	f2fs_balance_fs(sbi);
> -
>  	inode = f2fs_new_inode(dir, S_IFLNK | S_IRWXUGO);
>  	if (IS_ERR(inode))
>  		return PTR_ERR(inode);
> @@ -353,6 +352,8 @@ static int f2fs_symlink(struct inode *dir, struct dentry *dentry,
>  		inode->i_op = &f2fs_symlink_inode_operations;
>  	inode->i_mapping->a_ops = &f2fs_dblock_aops;
> 
> +	f2fs_balance_fs(sbi);
> +
>  	f2fs_lock_op(sbi);
>  	err = f2fs_add_link(dentry, inode);
>  	if (err)
> @@ -433,8 +434,6 @@ static int f2fs_mkdir(struct inode *dir, struct dentry *dentry, umode_t
> mode)
>  	struct inode *inode;
>  	int err;
> 
> -	f2fs_balance_fs(sbi);
> -
>  	inode = f2fs_new_inode(dir, S_IFDIR | mode);
>  	if (IS_ERR(inode))
>  		return PTR_ERR(inode);
> @@ -444,6 +443,8 @@ static int f2fs_mkdir(struct inode *dir, struct dentry *dentry, umode_t
> mode)
>  	inode->i_mapping->a_ops = &f2fs_dblock_aops;
>  	mapping_set_gfp_mask(inode->i_mapping, GFP_F2FS_HIGH_ZERO);
> 
> +	f2fs_balance_fs(sbi);
> +
>  	set_inode_flag(F2FS_I(inode), FI_INC_LINK);
>  	f2fs_lock_op(sbi);
>  	err = f2fs_add_link(dentry, inode);
> @@ -481,8 +482,6 @@ static int f2fs_mknod(struct inode *dir, struct dentry *dentry,
>  	struct inode *inode;
>  	int err = 0;
> 
> -	f2fs_balance_fs(sbi);
> -
>  	inode = f2fs_new_inode(dir, mode);
>  	if (IS_ERR(inode))
>  		return PTR_ERR(inode);
> @@ -490,6 +489,8 @@ static int f2fs_mknod(struct inode *dir, struct dentry *dentry,
>  	init_special_inode(inode, inode->i_mode, rdev);
>  	inode->i_op = &f2fs_special_inode_operations;
> 
> +	f2fs_balance_fs(sbi);
> +
>  	f2fs_lock_op(sbi);
>  	err = f2fs_add_link(dentry, inode);
>  	if (err)
> @@ -516,9 +517,6 @@ static int __f2fs_tmpfile(struct inode *dir, struct dentry *dentry,
>  	struct inode *inode;
>  	int err;
> 
> -	if (!whiteout)
> -		f2fs_balance_fs(sbi);
> -
>  	inode = f2fs_new_inode(dir, mode);
>  	if (IS_ERR(inode))
>  		return PTR_ERR(inode);
> @@ -530,6 +528,8 @@ static int __f2fs_tmpfile(struct inode *dir, struct dentry *dentry,
>  		inode->i_op = &f2fs_file_inode_operations;
>  		inode->i_fop = &f2fs_file_operations;
>  		inode->i_mapping->a_ops = &f2fs_dblock_aops;
> +
> +		f2fs_balance_fs(sbi);
>  	}
> 
>  	f2fs_lock_op(sbi);
> @@ -604,8 +604,6 @@ static int f2fs_rename(struct inode *old_dir, struct dentry *old_dentry,
>  		goto out;
>  	}
> 
> -	f2fs_balance_fs(sbi);
> -
>  	old_entry = f2fs_find_entry(old_dir, &old_dentry->d_name, &old_page);
>  	if (!old_entry)
>  		goto out;
> @@ -635,6 +633,8 @@ static int f2fs_rename(struct inode *old_dir, struct dentry *old_dentry,
>  		if (!new_entry)
>  			goto out_whiteout;
> 
> +		f2fs_balance_fs(sbi);

If we are in RENAME_WHITEOUT case, move f2fs_balance_fs here seems a bit late.
How about let __f2fs_tmpfile do reclaim for both whiteout and tmpfile case
itself, and do reclaim exclude whiteout case here?

Thanks,

> +
>  		f2fs_lock_op(sbi);
> 
>  		err = acquire_orphan_inode(sbi);
> @@ -666,6 +666,8 @@ static int f2fs_rename(struct inode *old_dir, struct dentry *old_dentry,
>  		update_inode_page(old_inode);
>  		update_inode_page(new_inode);
>  	} else {
> +		f2fs_balance_fs(sbi);
> +
>  		f2fs_lock_op(sbi);
> 
>  		err = f2fs_add_link(new_dentry, old_inode);
> @@ -763,8 +765,6 @@ static int f2fs_cross_rename(struct inode *old_dir, struct dentry
> *old_dentry,
>  								new_inode)))
>  		return -EPERM;
> 
> -	f2fs_balance_fs(sbi);
> -
>  	old_entry = f2fs_find_entry(old_dir, &old_dentry->d_name, &old_page);
>  	if (!old_entry)
>  		goto out;
> @@ -807,6 +807,8 @@ static int f2fs_cross_rename(struct inode *old_dir, struct dentry
> *old_dentry,
>  			goto out_new_dir;
>  	}
> 
> +	f2fs_balance_fs(sbi);
> +
>  	f2fs_lock_op(sbi);
> 
>  	err = update_dent_inode(old_inode, new_inode, &new_dentry->d_name);
> --
> 2.5.4 (Apple Git-61)