Commit 430f163b authored by Chao Yu's avatar Chao Yu Committed by Jaegeuk Kim
Browse files

f2fs: adjust readahead block number during recovery 



In a fragmented image, entries in dnode block list may locate in
incontiguous physical block address space, however, in recovery flow,
we will always readahead BIO_MAX_VECS size blocks, so in such case,
current readahead policy is low efficient, let's adjust readahead
window size dynamically based on consecutiveness of dnode blocks.

Signed-off-by: default avatarChao Yu <chao@kernel.org>
Signed-off-by: default avatarJaegeuk Kim <jaegeuk@kernel.org>
parent 6d18762e

fs/f2fs/checkpoint.c

+6 −2
Original line number Diff line number Diff line
@@ -282,18 +282,22 @@ int f2fs_ra_meta_pages(struct f2fs_sb_info *sbi, block_t start, int nrpages, 
	return blkno - start;

}



void f2fs_ra_meta_pages_cond(struct f2fs_sb_info *sbi, pgoff_t index)

void f2fs_ra_meta_pages_cond(struct f2fs_sb_info *sbi, pgoff_t index,

							unsigned int ra_blocks)

{

	struct page *page;

	bool readahead = false;



	if (ra_blocks == RECOVERY_MIN_RA_BLOCKS)

		return;



	page = find_get_page(META_MAPPING(sbi), index);

	if (!page || !PageUptodate(page))

		readahead = true;

	f2fs_put_page(page, 0);



	if (readahead)

		f2fs_ra_meta_pages(sbi, index, BIO_MAX_VECS, META_POR, true);

		f2fs_ra_meta_pages(sbi, index, ra_blocks, META_POR, true);

}



static int __f2fs_write_meta_page(struct page *page,

fs/f2fs/f2fs.h

+5 −1
Original line number Diff line number Diff line
@@ -590,6 +590,9 @@ enum { 
/* number of extent info in extent cache we try to shrink */

#define EXTENT_CACHE_SHRINK_NUMBER	128



#define RECOVERY_MAX_RA_BLOCKS		BIO_MAX_VECS

#define RECOVERY_MIN_RA_BLOCKS		1



struct rb_entry {

	struct rb_node rb_node;		/* rb node located in rb-tree */

	union {
@@ -3651,7 +3654,8 @@ bool f2fs_is_valid_blkaddr(struct f2fs_sb_info *sbi, 
					block_t blkaddr, int type);

int f2fs_ra_meta_pages(struct f2fs_sb_info *sbi, block_t start, int nrpages,

			int type, bool sync);

void f2fs_ra_meta_pages_cond(struct f2fs_sb_info *sbi, pgoff_t index);

void f2fs_ra_meta_pages_cond(struct f2fs_sb_info *sbi, pgoff_t index,

							unsigned int ra_blocks);

long f2fs_sync_meta_pages(struct f2fs_sb_info *sbi, enum page_type type,

			long nr_to_write, enum iostat_type io_type);

void f2fs_add_ino_entry(struct f2fs_sb_info *sbi, nid_t ino, int type);

fs/f2fs/recovery.c

+24 −3
Original line number Diff line number Diff line
@@ -343,6 +343,19 @@ static int recover_inode(struct inode *inode, struct page *page) 
	return 0;

}



static unsigned int adjust_por_ra_blocks(struct f2fs_sb_info *sbi,

				unsigned int ra_blocks, unsigned int blkaddr,

				unsigned int next_blkaddr)

{

	if (blkaddr + 1 == next_blkaddr)

		ra_blocks = min_t(unsigned int, RECOVERY_MAX_RA_BLOCKS,

							ra_blocks * 2);

	else if (next_blkaddr % sbi->blocks_per_seg)

		ra_blocks = max_t(unsigned int, RECOVERY_MIN_RA_BLOCKS,

							ra_blocks / 2);

	return ra_blocks;

}



static int find_fsync_dnodes(struct f2fs_sb_info *sbi, struct list_head *head,

				bool check_only)

{
@@ -350,6 +363,7 @@ static int find_fsync_dnodes(struct f2fs_sb_info *sbi, struct list_head *head, 
	struct page *page = NULL;

	block_t blkaddr;

	unsigned int loop_cnt = 0;

	unsigned int ra_blocks = RECOVERY_MAX_RA_BLOCKS;

	unsigned int free_blocks = MAIN_SEGS(sbi) * sbi->blocks_per_seg -

						valid_user_blocks(sbi);

	int err = 0;
@@ -424,11 +438,14 @@ static int find_fsync_dnodes(struct f2fs_sb_info *sbi, struct list_head *head, 
			break;

		}



		ra_blocks = adjust_por_ra_blocks(sbi, ra_blocks, blkaddr,

						next_blkaddr_of_node(page));



		/* check next segment */

		blkaddr = next_blkaddr_of_node(page);

		f2fs_put_page(page, 1);



		f2fs_ra_meta_pages_cond(sbi, blkaddr);

		f2fs_ra_meta_pages_cond(sbi, blkaddr, ra_blocks);

	}

	return err;

}
@@ -704,6 +721,7 @@ static int recover_data(struct f2fs_sb_info *sbi, struct list_head *inode_list, 
	struct page *page = NULL;

	int err = 0;

	block_t blkaddr;

	unsigned int ra_blocks = RECOVERY_MAX_RA_BLOCKS;



	/* get node pages in the current segment */

	curseg = CURSEG_I(sbi, CURSEG_WARM_NODE);
@@ -715,8 +733,6 @@ static int recover_data(struct f2fs_sb_info *sbi, struct list_head *inode_list, 
		if (!f2fs_is_valid_blkaddr(sbi, blkaddr, META_POR))

			break;



		f2fs_ra_meta_pages_cond(sbi, blkaddr);



		page = f2fs_get_tmp_page(sbi, blkaddr);

		if (IS_ERR(page)) {

			err = PTR_ERR(page);
@@ -759,9 +775,14 @@ static int recover_data(struct f2fs_sb_info *sbi, struct list_head *inode_list, 
		if (entry->blkaddr == blkaddr)

			list_move_tail(&entry->list, tmp_inode_list);

next:

		ra_blocks = adjust_por_ra_blocks(sbi, ra_blocks, blkaddr,

						next_blkaddr_of_node(page));



		/* check next segment */

		blkaddr = next_blkaddr_of_node(page);

		f2fs_put_page(page, 1);



		f2fs_ra_meta_pages_cond(sbi, blkaddr, ra_blocks);

	}

	if (!err)

		f2fs_allocate_new_segments(sbi);