2018-11-14 09:25:36

by Chengguang Xu

Subject: [PATCH] ext4: remove redundant condition check

ext4_xattr_destroy_cache() can handle NULL pointer correctly,
so there is no need to check NULL pointer before calling
ext4_xattr_destroy_cache().

Signed-off-by: Chengguang Xu <[email protected]>
---
fs/ext4/super.c | 29 +++++++++++++----------------
1 file changed, 13 insertions(+), 16 deletions(-)

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 53ff6c2a26ed..30d4a4e69de8 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1000,14 +1000,13 @@ static void ext4_put_super(struct super_block *sb)
invalidate_bdev(sbi->journal_bdev);
ext4_blkdev_remove(sbi);
}
- if (sbi->s_ea_inode_cache) {
- ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
- sbi->s_ea_inode_cache = NULL;
- }
- if (sbi->s_ea_block_cache) {
- ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
- sbi->s_ea_block_cache = NULL;
- }
+
+ ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
+ sbi->s_ea_inode_cache = NULL;
+
+ ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
+ sbi->s_ea_block_cache = NULL;
+
if (sbi->s_mmp_tsk)
kthread_stop(sbi->s_mmp_tsk);
brelse(sbi->s_sbh);
@@ -4522,14 +4521,12 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
if (EXT4_SB(sb)->rsv_conversion_wq)
destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
failed_mount_wq:
- if (sbi->s_ea_inode_cache) {
- ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
- sbi->s_ea_inode_cache = NULL;
- }
- if (sbi->s_ea_block_cache) {
- ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
- sbi->s_ea_block_cache = NULL;
- }
+ ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
+ sbi->s_ea_inode_cache = NULL;
+
+ ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
+ sbi->s_ea_block_cache = NULL;
+
if (sbi->s_journal) {
jbd2_journal_destroy(sbi->s_journal);
sbi->s_journal = NULL;
--
2.17.2

2018-11-27 20:41:20

by Jan Kara

Subject: Re: [PATCH] ext4: remove redundant condition check

On Wed 14-11-18 07:24:48, Chengguang Xu wrote:
> ext4_xattr_destroy_cache() can handle NULL pointer correctly,
> so there is no need to check NULL pointer before calling
> ext4_xattr_destroy_cache().
>
> Signed-off-by: Chengguang Xu <[email protected]>

The patch looks good. You can add:

Reviewed-by: Jan Kara <[email protected]>

Honza

> ---
> fs/ext4/super.c | 29 +++++++++++++----------------
> 1 file changed, 13 insertions(+), 16 deletions(-)
>
> diff --git a/fs/ext4/super.c b/fs/ext4/super.c
> index 53ff6c2a26ed..30d4a4e69de8 100644
> --- a/fs/ext4/super.c
> +++ b/fs/ext4/super.c
> @@ -1000,14 +1000,13 @@ static void ext4_put_super(struct super_block *sb)
> invalidate_bdev(sbi->journal_bdev);
> ext4_blkdev_remove(sbi);
> }
> - if (sbi->s_ea_inode_cache) {
> - ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
> - sbi->s_ea_inode_cache = NULL;
> - }
> - if (sbi->s_ea_block_cache) {
> - ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
> - sbi->s_ea_block_cache = NULL;
> - }
> +
> + ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
> + sbi->s_ea_inode_cache = NULL;
> +
> + ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
> + sbi->s_ea_block_cache = NULL;
> +
> if (sbi->s_mmp_tsk)
> kthread_stop(sbi->s_mmp_tsk);
> brelse(sbi->s_sbh);
> @@ -4522,14 +4521,12 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
> if (EXT4_SB(sb)->rsv_conversion_wq)
> destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
> failed_mount_wq:
> - if (sbi->s_ea_inode_cache) {
> - ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
> - sbi->s_ea_inode_cache = NULL;
> - }
> - if (sbi->s_ea_block_cache) {
> - ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
> - sbi->s_ea_block_cache = NULL;
> - }
> + ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
> + sbi->s_ea_inode_cache = NULL;
> +
> + ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
> + sbi->s_ea_block_cache = NULL;
> +
> if (sbi->s_journal) {
> jbd2_journal_destroy(sbi->s_journal);
> sbi->s_journal = NULL;
> --
> 2.17.2
>
--
Jan Kara <[email protected]>
SUSE Labs, CR

2018-12-04 05:25:32

by Theodore Ts'o

Subject: Re: [PATCH] ext4: remove redundant condition check

On Tue, Nov 27, 2018 at 10:43:58AM +0100, Jan Kara wrote:
> On Wed 14-11-18 07:24:48, Chengguang Xu wrote:
> > ext4_xattr_destroy_cache() can handle NULL pointer correctly,
> > so there is no need to check NULL pointer before calling
> > ext4_xattr_destroy_cache().
> >
> > Signed-off-by: Chengguang Xu <[email protected]>
>
> The patch looks good. You can add:
>
> Reviewed-by: Jan Kara <[email protected]>

Thanks, applied.

- Ted