Re: [PATCH] ext4: Change list_for_each to list_for_each_entry

From: harshad shirwadkar
Date: Fri Jan 08 2021 - 18:01:33 EST


Hey Daejun,

I was taking a look at this again, and just noticed one quick thing:

On Tue, Jan 5, 2021 at 1:56 PM harshad shirwadkar
<harshadshirwadkar@xxxxxxxxx> wrote:
>
> Looks good to me, thanks!
>
> Reviewed-by: Harshad Shirwadkar <harshadshirwadkar@xxxxxxxxx>
>
> On Wed, Dec 30, 2020 at 5:56 PM Daejun Park <daejun7.park@xxxxxxxxxxx> wrote:
> >
> > list_for_each + list_entry can be changed to list_for_each_entry
> > It reduces number of variables and lines.
> >
> > Signed-off-by: Daejun Park <daejun7.park@xxxxxxxxxxx>
> > ---
> > fs/ext4/fast_commit.c | 7 ++-----
> > 1 file changed, 2 insertions(+), 5 deletions(-)
> >
> > diff --git a/fs/ext4/fast_commit.c b/fs/ext4/fast_commit.c
> > index 5b6bb3ef0f33..dc58471971db 100644
> > --- a/fs/ext4/fast_commit.c
> > +++ b/fs/ext4/fast_commit.c
> > @@ -915,13 +915,11 @@ static int ext4_fc_submit_inode_data_all(journal_t *journal)
> > struct super_block *sb = (struct super_block *)(journal->j_private);
> > struct ext4_sb_info *sbi = EXT4_SB(sb);
> > struct ext4_inode_info *ei;
> > - struct list_head *pos;
> > int ret = 0;
> >
> > spin_lock(&sbi->s_fc_lock);
> > ext4_set_mount_flag(sb, EXT4_MF_FC_COMMITTING);
> > - list_for_each(pos, &sbi->s_fc_q[FC_Q_MAIN]) {
> > - ei = list_entry(pos, struct ext4_inode_info, i_fc_list);
> > + list_for_each_entry(ei, &sbi->s_fc_q[FC_Q_MAIN], i_fc_list) {
> > ext4_set_inode_state(&ei->vfs_inode, EXT4_STATE_FC_COMMITTING);
> > while (atomic_read(&ei->i_fc_updates)) {
> > DEFINE_WAIT(wait);
> > @@ -1099,8 +1097,7 @@ static int ext4_fc_perform_commit(journal_t *journal)
> > goto out;
> > }
> >
> > - list_for_each(pos, &sbi->s_fc_q[FC_Q_MAIN]) {
> > - iter = list_entry(pos, struct ext4_inode_info, i_fc_list);
Variable "pos" isn't used anymore after this patch. You removed it for
the ext4_fc_submit_inode_data_all() function, but missed removing it
in this function. That's throwing me a warning.

Thanks,
Harshad

> > + list_for_each_entry(iter, &sbi->s_fc_q[FC_Q_MAIN], i_fc_list) {
> > inode = &iter->vfs_inode;
> > if (!ext4_test_inode_state(inode, EXT4_STATE_FC_COMMITTING))
> > continue;
> > --
> > 2.25.1
> >