On Mon 03-06-24 21:15:24, Junchao Sun wrote:
> Using pahole, we can see that there are some padding holes
> in the current ext4_inode_info structure. Adjusting the
> layout of ext4_inode_info can reduce these holes,
> resulting in the size of the structure decreasing
> from 2424 bytes to 2408 bytes.
But AFAICT this will save two holes 4 bytes each so only 8 bytes in total?
Not 16?
>
> Signed-off-by: Junchao Sun <sunjunchao2870@xxxxxxxxx>
Otherwise looks good. Feel free to add:
Reviewed-by: Jan Kara <jack@xxxxxxx>
Honza
> ---
> fs/ext4/ext4.h | 10 +++++-----
> 1 file changed, 5 insertions(+), 5 deletions(-)
>
> diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
> index 023571f8dd1b..42bcd4f749a8 100644
> --- a/fs/ext4/ext4.h
> +++ b/fs/ext4/ext4.h
> @@ -1055,6 +1055,7 @@ struct ext4_inode_info {
>
> /* Number of ongoing updates on this inode */
> atomic_t i_fc_updates;
> + atomic_t i_unwritten; /* Nr. of inflight conversions pending */
>
> /* Fast commit wait queue for this inode */
> wait_queue_head_t i_fc_wait;
> @@ -1103,6 +1104,10 @@ struct ext4_inode_info {
>
> /* mballoc */
> atomic_t i_prealloc_active;
> +
> + /* allocation reservation info for delalloc */
> + /* In case of bigalloc, this refer to clusters rather than blocks */
> + unsigned int i_reserved_data_blocks;
> struct rb_root i_prealloc_node;
> rwlock_t i_prealloc_lock;
>
> @@ -1119,10 +1124,6 @@ struct ext4_inode_info {
> /* ialloc */
> ext4_group_t i_last_alloc_group;
>
> - /* allocation reservation info for delalloc */
> - /* In case of bigalloc, this refer to clusters rather than blocks */
> - unsigned int i_reserved_data_blocks;
> -
> /* pending cluster reservations for bigalloc file systems */
> struct ext4_pending_tree i_pending_tree;
>
> @@ -1146,7 +1147,6 @@ struct ext4_inode_info {
> */
> struct list_head i_rsv_conversion_list;
> struct work_struct i_rsv_conversion_work;
> - atomic_t i_unwritten; /* Nr. of inflight conversions pending */
>
> spinlock_t i_block_reservation_lock;
>
> --
> 2.39.2
>
--
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR
