[PATCH] btrfs: remove pointless empty list check when reading delayed dir indexes

[PATCH] btrfs: remove pointless empty list check when reading delayed dir indexes

[fdmanana]

From: Filipe Manana <fdmanana@suse.com>

At btrfs_readdir_delayed_dir_index(), called when reading a directory, we
have this check for an empty list to return immediately, but it's not
needed since list_for_each_entry_safe(), called immediately after, is
prepared to deal with an empty list, it simply does nothing. So remove
the empty list check.

Besides shorter source code, it also slightly reduces the binary text
size:

  Before this change:

    $ size fs/btrfs/btrfs.ko
       text	   data	    bss	    dec	    hex	filename
    1609408	 167269	  16864	1793541	 1b5e05	fs/btrfs/btrfs.ko

  After this change:

    $ size fs/btrfs/btrfs.ko
       text	   data	    bss	    dec	    hex	filename
    1609392	 167269	  16864	1793525	 1b5df5	fs/btrfs/btrfs.ko

Signed-off-by: Filipe Manana <fdmanana@suse.com>
---
 fs/btrfs/delayed-inode.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/fs/btrfs/delayed-inode.c b/fs/btrfs/delayed-inode.c
index 6d51db066503..85dcf0024137 100644
--- a/fs/btrfs/delayed-inode.c
+++ b/fs/btrfs/delayed-inode.c
@@ -1736,9 +1736,6 @@ int btrfs_readdir_delayed_dir_index(struct dir_context *ctx,
 	int over = 0;
 	unsigned char d_type;
 
-	if (list_empty(ins_list))
-		return 0;
-
 	/*
 	 * Changing the data of the delayed item is impossible. So
 	 * we needn't lock them. And we have held i_mutex of the
-- 
2.34.1

Re: [PATCH] btrfs: remove pointless empty list check when reading delayed dir indexes

[David Sterba]

On Sun, Aug 13, 2023 at 04:03:28PM +0100, fdmanana@kernel.org wrote:
> From: Filipe Manana <fdmanana@suse.com>
> 
> At btrfs_readdir_delayed_dir_index(), called when reading a directory, we
> have this check for an empty list to return immediately, but it's not
> needed since list_for_each_entry_safe(), called immediately after, is
> prepared to deal with an empty list, it simply does nothing. So remove
> the empty list check.
> 
> Besides shorter source code, it also slightly reduces the binary text
> size:
> 
>   Before this change:
> 
>     $ size fs/btrfs/btrfs.ko
>        text	   data	    bss	    dec	    hex	filename
>     1609408	 167269	  16864	1793541	 1b5e05	fs/btrfs/btrfs.ko
> 
>   After this change:
> 
>     $ size fs/btrfs/btrfs.ko
>        text	   data	    bss	    dec	    hex	filename
>     1609392	 167269	  16864	1793525	 1b5df5	fs/btrfs/btrfs.ko
> 
> Signed-off-by: Filipe Manana <fdmanana@suse.com>

That one has also been in misc-next for some time, thanks.