Re: [f2fs-dev] [PATCH 3/3] f2fs: use macro for code readability

[Jaegeuk Kim <jaegeuk@kernel.org>]

On Wed, Aug 20, 2014 at 06:38:40PM +0800, Chao Yu wrote:
> This patch introduces DEF_NIDS_PER_INODE/GET_ORPHAN_BLOCKS/F2FS_CP_PARK_NUM macro

F2FS_CP_PACKS?

> instead of numbers in code for readability.
> 
> Signed-off-by: Chao Yu <chao2.yu@samsung.com>
> ---
>  fs/f2fs/checkpoint.c    | 21 ++++++++++-----------
>  include/linux/f2fs_fs.h | 13 ++++++++++---
>  2 files changed, 20 insertions(+), 14 deletions(-)
> 
> diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c
> index 6aeed5b..b0b6079 100644
> --- a/fs/f2fs/checkpoint.c
> +++ b/fs/f2fs/checkpoint.c
> @@ -446,8 +446,8 @@ static void write_orphan_inodes(struct f2fs_sb_info *sbi, block_t start_blk)
>  	struct f2fs_orphan_block *orphan_blk = NULL;
>  	unsigned int nentries = 0;
>  	unsigned short index;
> -	unsigned short orphan_blocks = (unsigned short)((sbi->n_orphans +
> -		(F2FS_ORPHANS_PER_BLOCK - 1)) / F2FS_ORPHANS_PER_BLOCK);
> +	unsigned short orphan_blocks =
> +			(unsigned short)GET_ORPHAN_BLOCKS(sbi->n_orphans);
>  	struct page *page = NULL;
>  	struct ino_entry *orphan = NULL;
>  
> @@ -825,7 +825,7 @@ static void do_checkpoint(struct f2fs_sb_info *sbi, bool is_umount)
>  	ckpt->elapsed_time = cpu_to_le64(get_mtime(sbi));
>  	ckpt->valid_block_count = cpu_to_le64(valid_user_blocks(sbi));
>  	ckpt->free_segment_count = cpu_to_le32(free_segments(sbi));
> -	for (i = 0; i < 3; i++) {
> +	for (i = 0; i < NR_CURSEG_NODE_TYPE; i++) {
>  		ckpt->cur_node_segno[i] =
>  			cpu_to_le32(curseg_segno(sbi, i + CURSEG_HOT_NODE));
>  		ckpt->cur_node_blkoff[i] =
> @@ -833,7 +833,7 @@ static void do_checkpoint(struct f2fs_sb_info *sbi, bool is_umount)
>  		ckpt->alloc_type[i + CURSEG_HOT_NODE] =
>  				curseg_alloc_type(sbi, i + CURSEG_HOT_NODE);
>  	}
> -	for (i = 0; i < 3; i++) {
> +	for (i = 0; i < NR_CURSEG_DATA_TYPE; i++) {
>  		ckpt->cur_data_segno[i] =
>  			cpu_to_le32(curseg_segno(sbi, i + CURSEG_HOT_DATA));
>  		ckpt->cur_data_blkoff[i] =
> @@ -848,24 +848,23 @@ static void do_checkpoint(struct f2fs_sb_info *sbi, bool is_umount)
>  
>  	/* 2 cp  + n data seg summary + orphan inode blocks */
>  	data_sum_blocks = npages_for_summary_flush(sbi);
> -	if (data_sum_blocks < 3)
> +	if (data_sum_blocks < NR_CURSEG_DATA_TYPE)
>  		set_ckpt_flags(ckpt, CP_COMPACT_SUM_FLAG);
>  	else
>  		clear_ckpt_flags(ckpt, CP_COMPACT_SUM_FLAG);
>  
> -	orphan_blocks = (sbi->n_orphans + F2FS_ORPHANS_PER_BLOCK - 1)
> -					/ F2FS_ORPHANS_PER_BLOCK;
> +	orphan_blocks = GET_ORPHAN_BLOCKS(sbi->n_orphans);
>  	ckpt->cp_pack_start_sum = cpu_to_le32(1 + cp_payload_blks +
>  			orphan_blocks);
>  
>  	if (is_umount) {
>  		set_ckpt_flags(ckpt, CP_UMOUNT_FLAG);
> -		ckpt->cp_pack_total_block_count = cpu_to_le32(2 +
> +		ckpt->cp_pack_total_block_count = cpu_to_le32(F2FS_CP_PARK_NUM +
>  				cp_payload_blks + data_sum_blocks +
>  				orphan_blocks + NR_CURSEG_NODE_TYPE);
>  	} else {
>  		clear_ckpt_flags(ckpt, CP_UMOUNT_FLAG);
> -		ckpt->cp_pack_total_block_count = cpu_to_le32(2 +
> +		ckpt->cp_pack_total_block_count = cpu_to_le32(F2FS_CP_PARK_NUM +
>  				cp_payload_blks + data_sum_blocks +
>  				orphan_blocks);
>  	}
> @@ -999,8 +998,8 @@ void init_ino_entry_info(struct f2fs_sb_info *sbi)
>  	 * for cp pack we can have max 1020*504 orphan entries
>  	 */
>  	sbi->n_orphans = 0;
> -	sbi->max_orphans = (sbi->blocks_per_seg - 2 - NR_CURSEG_TYPE)
> -				* F2FS_ORPHANS_PER_BLOCK;
> +	sbi->max_orphans = (sbi->blocks_per_seg - F2FS_CP_PARK_NUM -
> +			NR_CURSEG_TYPE) * F2FS_ORPHANS_PER_BLOCK;
>  }
>  
>  int __init create_checkpoint_caches(void)
> diff --git a/include/linux/f2fs_fs.h b/include/linux/f2fs_fs.h
> index 0ed77f3..f3cca5b 100644
> --- a/include/linux/f2fs_fs.h
> +++ b/include/linux/f2fs_fs.h
> @@ -90,6 +90,8 @@ struct f2fs_super_block {
>  #define CP_ORPHAN_PRESENT_FLAG	0x00000002
>  #define CP_UMOUNT_FLAG		0x00000001
>  
> +#define F2FS_CP_PARK_NUM	2	/* # of checkpoint packs */
> +
>  struct f2fs_checkpoint {
>  	__le64 checkpoint_ver;		/* checkpoint block version number */
>  	__le64 user_block_count;	/* # of user blocks */
> @@ -126,6 +128,9 @@ struct f2fs_checkpoint {
>   */
>  #define F2FS_ORPHANS_PER_BLOCK	1020
>  
> +#define GET_ORPHAN_BLOCKS(n)	((n + F2FS_ORPHANS_PER_BLOCK - 1) / \
> +					F2FS_ORPHANS_PER_BLOCK)
> +
>  struct f2fs_orphan_block {
>  	__le32 ino[F2FS_ORPHANS_PER_BLOCK];	/* inode numbers */
>  	__le32 reserved;	/* reserved */
> @@ -147,6 +152,7 @@ struct f2fs_extent {
>  #define F2FS_NAME_LEN		255
>  #define F2FS_INLINE_XATTR_ADDRS	50	/* 200 bytes for inline xattrs */
>  #define DEF_ADDRS_PER_INODE	923	/* Address Pointers in an Inode */
> +#define DEF_NIDS_PER_INODE	5	/* Node IDs in an Inode */
>  #define ADDRS_PER_INODE(fi)	addrs_per_inode(fi)
>  #define ADDRS_PER_BLOCK		1018	/* Address Pointers in a Direct Block */
>  #define NIDS_PER_BLOCK		1018	/* Node IDs in an Indirect Block */
> @@ -166,8 +172,9 @@ struct f2fs_extent {
>  #define MAX_INLINE_DATA		(sizeof(__le32) * (DEF_ADDRS_PER_INODE - \
>  						F2FS_INLINE_XATTR_ADDRS - 1))
>  
> -#define INLINE_DATA_OFFSET	(PAGE_CACHE_SIZE - sizeof(struct node_footer) \
> -			- sizeof(__le32) * (DEF_ADDRS_PER_INODE + 5 - 1))
> +#define INLINE_DATA_OFFSET	(PAGE_CACHE_SIZE - sizeof(struct node_footer) -\
> +				sizeof(__le32) * (DEF_ADDRS_PER_INODE + \
> +				DEF_NIDS_PER_INODE - 1))
>  
>  struct f2fs_inode {
>  	__le16 i_mode;			/* file mode */
> @@ -197,7 +204,7 @@ struct f2fs_inode {
>  
>  	__le32 i_addr[DEF_ADDRS_PER_INODE];	/* Pointers to data blocks */
>  
> -	__le32 i_nid[5];		/* direct(2), indirect(2),
> +	__le32 i_nid[DEF_NIDS_PER_INODE];	/* direct(2), indirect(2),
>  						double_indirect(1) node id */
>  } __packed;
>  
> -- 
> 2.0.1.474.g72c7794
> 
> 
> 
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