Re: [f2fs-dev] [PATCH V3 2/2] f2fs: read contiguous sit entry pages by merging for mount performance

[Jaegeuk Kim <jaegeuk.kim@samsung.com>]

Hi,

2013-11-22 (금), 09:09 +0800, Chao Yu:
> Previously we read sit entries page one by one, this method lost the chance 
> of reading contiguous page together. So we read pages as contiguous as 
> possible for better mount performance.
> 
> change log:
>  o merge judgements/use 'Continue' or 'Break' instead of 'Goto' as Gu Zheng 
>    suggested.
>  o add mark_page_accessed() before release page to delay VM reclaiming.
>  o remove '*order' for simplification of function as Jaegeuk Kim suggested.
> 
> Signed-off-by: Chao Yu <chao2.yu@samsung.com>
> ---
>  fs/f2fs/segment.c |  103 +++++++++++++++++++++++++++++++++++++++--------------
>  fs/f2fs/segment.h |    2 ++
>  2 files changed, 78 insertions(+), 27 deletions(-)
> 
> diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
> index 8149eba..998e7d3 100644
> --- a/fs/f2fs/segment.c
> +++ b/fs/f2fs/segment.c
> @@ -14,6 +14,7 @@
>  #include <linux/blkdev.h>
>  #include <linux/prefetch.h>
>  #include <linux/vmalloc.h>
> +#include <linux/swap.h>
>  
>  #include "f2fs.h"
>  #include "segment.h"
> @@ -1488,41 +1489,89 @@ static int build_curseg(struct f2fs_sb_info *sbi)
>  	return restore_curseg_summaries(sbi);
>  }
>  
> +static int ra_sit_pages(struct f2fs_sb_info *sbi, int start, int nrpages)
> +{
> +	struct address_space *mapping = sbi->meta_inode->i_mapping;
> +	struct page *page;
> +	block_t blk_addr, prev_blk_addr = 0;
> +	int sit_blk_cnt = SIT_BLK_CNT(sbi);
> +	int blkno = start;
> +
> +	for (; blkno < start + nrpages && blkno < sit_blk_cnt; blkno++) {
> +
> +		blk_addr = current_sit_addr(sbi, start * SIT_ENTRY_PER_BLOCK);

Should be:
	blk_addr = current_sit_addr(sbi, blkno * SIT_ENTRY_PER_BLOCK);
	                                -------
I'll fix this and merge the patch though.
Thanks,

-- 
Jaegeuk Kim
Samsung