ext4: remove unused metadata accounting variables

Two variables in ext4_inode_info, i_reserved_meta_blocks and
i_allocated_meta_blocks, are unused.  Removing them saves a little
memory per in-memory inode and cleans up clutter in several tracepoints.
Adjust tracepoint output from ext4_alloc_da_blocks() for consistency
and fix a typo and whitespace near these changes.

Signed-off-by: Eric Whitney <enwlinux@gmail.com>
---
 fs/ext4/ext4.h              |  6 ++----
 fs/ext4/super.c             |  2 --
 include/trace/events/ext4.h | 35 ++++++++---------------------------
 3 files changed, 10 insertions(+), 33 deletions(-)

On Thu 13-07-17 10:57:08, Eric Whitney wrote:
> Two variables in ext4_inode_info, i_reserved_meta_blocks and
> i_allocated_meta_blocks, are unused.  Removing them saves a little
> memory per in-memory inode and cleans up clutter in several tracepoints.
> Adjust tracepoint output from ext4_alloc_da_blocks() for consistency
> and fix a typo and whitespace near these changes.
> 
> Signed-off-by: Eric Whitney <enwlinux@gmail.com>

Looks good. You can add:

Reviewed-by: Jan Kara <jack@suse.cz>

								Honza

> ---
>  fs/ext4/ext4.h              |  6 ++----
>  fs/ext4/super.c             |  2 --
>  include/trace/events/ext4.h | 35 ++++++++---------------------------
>  3 files changed, 10 insertions(+), 33 deletions(-)
> 
> diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
> index 9ebde0c..dcbcd9d 100644
> --- a/fs/ext4/ext4.h
> +++ b/fs/ext4/ext4.h
> @@ -961,7 +961,7 @@ struct ext4_inode_info {
>  	/*
>  	 * i_block_group is the number of the block group which contains
>  	 * this file's inode.  Constant across the lifetime of the inode,
> -	 * it is ued for making block allocation decisions - we try to
> +	 * it is used for making block allocation decisions - we try to
>  	 * place a file's data blocks near its inode block, and new inodes
>  	 * near to their parent directory's inode.
>  	 */
> @@ -1049,10 +1049,8 @@ struct ext4_inode_info {
>  	ext4_group_t	i_last_alloc_group;
>  
>  	/* allocation reservation info for delalloc */
> -	/* In case of bigalloc, these refer to clusters rather than blocks */
> +	/* In case of bigalloc, this refer to clusters rather than blocks */
>  	unsigned int i_reserved_data_blocks;
> -	unsigned int i_reserved_meta_blocks;
> -	unsigned int i_allocated_meta_blocks;
>  	ext4_lblk_t i_da_metadata_calc_last_lblock;
>  	int i_da_metadata_calc_len;
>  
> diff --git a/fs/ext4/super.c b/fs/ext4/super.c
> index f666042..94722df 100644
> --- a/fs/ext4/super.c
> +++ b/fs/ext4/super.c
> @@ -978,8 +978,6 @@ static struct inode *ext4_alloc_inode(struct super_block *sb)
>  	ei->i_es_shk_nr = 0;
>  	ei->i_es_shrink_lblk = 0;
>  	ei->i_reserved_data_blocks = 0;
> -	ei->i_reserved_meta_blocks = 0;
> -	ei->i_allocated_meta_blocks = 0;
>  	ei->i_da_metadata_calc_len = 0;
>  	ei->i_da_metadata_calc_last_lblock = 0;
>  	spin_lock_init(&(ei->i_block_reservation_lock));
> diff --git a/include/trace/events/ext4.h b/include/trace/events/ext4.h
> index dfae175..9c3bc38 100644
> --- a/include/trace/events/ext4.h
> +++ b/include/trace/events/ext4.h
> @@ -937,21 +937,19 @@ TRACE_EVENT(ext4_alloc_da_blocks,
>  	TP_STRUCT__entry(
>  		__field(	dev_t,	dev			)
>  		__field(	ino_t,	ino			)
> -		__field( unsigned int,	data_blocks	)
> -		__field( unsigned int,	meta_blocks	)
> +		__field( unsigned int,	data_blocks		)
>  	),
>  
>  	TP_fast_assign(
>  		__entry->dev	= inode->i_sb->s_dev;
>  		__entry->ino	= inode->i_ino;
>  		__entry->data_blocks = EXT4_I(inode)->i_reserved_data_blocks;
> -		__entry->meta_blocks = EXT4_I(inode)->i_reserved_meta_blocks;
>  	),
>  
> -	TP_printk("dev %d,%d ino %lu data_blocks %u meta_blocks %u",
> +	TP_printk("dev %d,%d ino %lu reserved_data_blocks %u",
>  		  MAJOR(__entry->dev), MINOR(__entry->dev),
>  		  (unsigned long) __entry->ino,
> -		  __entry->data_blocks, __entry->meta_blocks)
> +		  __entry->data_blocks)
>  );
>  
>  TRACE_EVENT(ext4_mballoc_alloc,
> @@ -1153,8 +1151,6 @@ TRACE_EVENT(ext4_da_update_reserve_space,
>  		__field(	__u64,	i_blocks		)
>  		__field(	int,	used_blocks		)
>  		__field(	int,	reserved_data_blocks	)
> -		__field(	int,	reserved_meta_blocks	)
> -		__field(	int,	allocated_meta_blocks	)
>  		__field(	int,	quota_claim		)
>  		__field(	__u16,	mode			)
>  	),
> @@ -1166,22 +1162,16 @@ TRACE_EVENT(ext4_da_update_reserve_space,
>  		__entry->used_blocks = used_blocks;
>  		__entry->reserved_data_blocks =
>  				EXT4_I(inode)->i_reserved_data_blocks;
> -		__entry->reserved_meta_blocks =
> -				EXT4_I(inode)->i_reserved_meta_blocks;
> -		__entry->allocated_meta_blocks =
> -				EXT4_I(inode)->i_allocated_meta_blocks;
>  		__entry->quota_claim = quota_claim;
>  		__entry->mode	= inode->i_mode;
>  	),
>  
>  	TP_printk("dev %d,%d ino %lu mode 0%o i_blocks %llu used_blocks %d "
> -		  "reserved_data_blocks %d reserved_meta_blocks %d "
> -		  "allocated_meta_blocks %d quota_claim %d",
> +		  "reserved_data_blocks %d quota_claim %d",
>  		  MAJOR(__entry->dev), MINOR(__entry->dev),
>  		  (unsigned long) __entry->ino,
>  		  __entry->mode, __entry->i_blocks,
>  		  __entry->used_blocks, __entry->reserved_data_blocks,
> -		  __entry->reserved_meta_blocks, __entry->allocated_meta_blocks,
>  		  __entry->quota_claim)
>  );
>  
> @@ -1195,7 +1185,6 @@ TRACE_EVENT(ext4_da_reserve_space,
>  		__field(	ino_t,	ino			)
>  		__field(	__u64,	i_blocks		)
>  		__field(	int,	reserved_data_blocks	)
> -		__field(	int,	reserved_meta_blocks	)
>  		__field(	__u16,  mode			)
>  	),
>  
> @@ -1204,17 +1193,15 @@ TRACE_EVENT(ext4_da_reserve_space,
>  		__entry->ino	= inode->i_ino;
>  		__entry->i_blocks = inode->i_blocks;
>  		__entry->reserved_data_blocks = EXT4_I(inode)->i_reserved_data_blocks;
> -		__entry->reserved_meta_blocks = EXT4_I(inode)->i_reserved_meta_blocks;
>  		__entry->mode	= inode->i_mode;
>  	),
>  
>  	TP_printk("dev %d,%d ino %lu mode 0%o i_blocks %llu "
> -		  "reserved_data_blocks %d reserved_meta_blocks %d",
> +		  "reserved_data_blocks %d",
>  		  MAJOR(__entry->dev), MINOR(__entry->dev),
>  		  (unsigned long) __entry->ino,
>  		  __entry->mode, __entry->i_blocks,
> -		  __entry->reserved_data_blocks,
> -		  __entry->reserved_meta_blocks)
> +		  __entry->reserved_data_blocks)
>  );
>  
>  TRACE_EVENT(ext4_da_release_space,
> @@ -1228,8 +1215,6 @@ TRACE_EVENT(ext4_da_release_space,
>  		__field(	__u64,	i_blocks		)
>  		__field(	int,	freed_blocks		)
>  		__field(	int,	reserved_data_blocks	)
> -		__field(	int,	reserved_meta_blocks	)
> -		__field(	int,	allocated_meta_blocks	)
>  		__field(	__u16,  mode			)
>  	),
>  
> @@ -1239,19 +1224,15 @@ TRACE_EVENT(ext4_da_release_space,
>  		__entry->i_blocks = inode->i_blocks;
>  		__entry->freed_blocks = freed_blocks;
>  		__entry->reserved_data_blocks = EXT4_I(inode)->i_reserved_data_blocks;
> -		__entry->reserved_meta_blocks = EXT4_I(inode)->i_reserved_meta_blocks;
> -		__entry->allocated_meta_blocks = EXT4_I(inode)->i_allocated_meta_blocks;
>  		__entry->mode	= inode->i_mode;
>  	),
>  
>  	TP_printk("dev %d,%d ino %lu mode 0%o i_blocks %llu freed_blocks %d "
> -		  "reserved_data_blocks %d reserved_meta_blocks %d "
> -		  "allocated_meta_blocks %d",
> +		  "reserved_data_blocks %d",
>  		  MAJOR(__entry->dev), MINOR(__entry->dev),
>  		  (unsigned long) __entry->ino,
>  		  __entry->mode, __entry->i_blocks,
> -		  __entry->freed_blocks, __entry->reserved_data_blocks,
> -		  __entry->reserved_meta_blocks, __entry->allocated_meta_blocks)
> +		  __entry->freed_blocks, __entry->reserved_data_blocks)
>  );
>  
>  DECLARE_EVENT_CLASS(ext4__bitmap_load,
> -- 
> 2.1.4
>

On Thu, Jul 13, 2017 at 05:58:32PM +0200, Jan Kara wrote:
> On Thu 13-07-17 10:57:08, Eric Whitney wrote:
> > Two variables in ext4_inode_info, i_reserved_meta_blocks and
> > i_allocated_meta_blocks, are unused.  Removing them saves a little
> > memory per in-memory inode and cleans up clutter in several tracepoints.
> > Adjust tracepoint output from ext4_alloc_da_blocks() for consistency
> > and fix a typo and whitespace near these changes.
> > 
> > Signed-off-by: Eric Whitney <enwlinux@gmail.com>
> 
> Looks good. You can add:
> 
> Reviewed-by: Jan Kara <jack@suse.cz>

Thanks, applied.

					- Ted