Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 87d6f890 authored by Jaegeuk Kim's avatar Jaegeuk Kim
Browse files

f2fs: avoid small data writes by skipping writepages 



This patch introduces nr_pages_to_skip(sbi, type) to determine writepages can
be skipped.
The dentry, node, and meta pages can be conrolled by F2FS without breaking the
FS consistency.

Signed-off-by: default avatarJaegeuk Kim <jaegeuk.kim@samsung.com>
parent f8b2c1f9

fs/f2fs/checkpoint.c

+2 −2
Original line number Original line Diff line number Diff line
@@ -187,7 +187,7 @@ static int f2fs_write_meta_pages(struct address_space *mapping, 
				struct writeback_control *wbc)

				struct writeback_control *wbc)

{

{

	struct f2fs_sb_info *sbi = F2FS_SB(mapping->host->i_sb);

	struct f2fs_sb_info *sbi = F2FS_SB(mapping->host->i_sb);

	int nrpages = MAX_BIO_BLOCKS(max_hw_blocks(sbi));

	int nrpages = nr_pages_to_skip(sbi, META);

	long written;

	long written;





	if (wbc->for_kupdate)

	if (wbc->for_kupdate)
@@ -682,7 +682,7 @@ retry: 
	inode = igrab(entry->inode);

	inode = igrab(entry->inode);

	spin_unlock(&sbi->dir_inode_lock);

	spin_unlock(&sbi->dir_inode_lock);

	if (inode) {

	if (inode) {

		filemap_flush(inode->i_mapping);

		filemap_fdatawrite(inode->i_mapping);

		iput(inode);

		iput(inode);

	} else {

	} else {

		/*

		/*

fs/f2fs/data.c

+4 −0
Original line number Original line Diff line number Diff line
@@ -868,6 +868,10 @@ static int f2fs_write_data_pages(struct address_space *mapping, 
	if (!mapping->a_ops->writepage)

	if (!mapping->a_ops->writepage)

		return 0;

		return 0;





	if (S_ISDIR(inode->i_mode) && wbc->sync_mode == WB_SYNC_NONE &&

			get_dirty_dents(inode) < nr_pages_to_skip(sbi, DATA))

		return 0;



	if (wbc->nr_to_write < MAX_DESIRED_PAGES_WP) {

	if (wbc->nr_to_write < MAX_DESIRED_PAGES_WP) {

		desired_nrtw = MAX_DESIRED_PAGES_WP;

		desired_nrtw = MAX_DESIRED_PAGES_WP;

		excess_nrtw = desired_nrtw - wbc->nr_to_write;

		excess_nrtw = desired_nrtw - wbc->nr_to_write;

fs/f2fs/node.c

+1 −7
Original line number Original line Diff line number Diff line
@@ -1198,12 +1198,6 @@ redirty_out: 
	return AOP_WRITEPAGE_ACTIVATE;

	return AOP_WRITEPAGE_ACTIVATE;

}

}





/*

 * It is very important to gather dirty pages and write at once, so that we can

 * submit a big bio without interfering other data writes.

 * Be default, 512 pages (2MB) * 3 node types, is more reasonable.

 */

#define COLLECT_DIRTY_NODES	1536

static int f2fs_write_node_pages(struct address_space *mapping,

static int f2fs_write_node_pages(struct address_space *mapping,

			    struct writeback_control *wbc)

			    struct writeback_control *wbc)

{

{
@@ -1214,7 +1208,7 @@ static int f2fs_write_node_pages(struct address_space *mapping, 
	f2fs_balance_fs_bg(sbi);

	f2fs_balance_fs_bg(sbi);





	/* collect a number of dirty node pages and write together */

	/* collect a number of dirty node pages and write together */

	if (get_pages(sbi, F2FS_DIRTY_NODES) < COLLECT_DIRTY_NODES)

	if (get_pages(sbi, F2FS_DIRTY_NODES) < nr_pages_to_skip(sbi, NODE))

		return 0;

		return 0;





	/* if mounting is failed, skip writing node pages */

	/* if mounting is failed, skip writing node pages */

fs/f2fs/segment.h

+19 −0
Original line number Original line Diff line number Diff line
@@ -664,3 +664,22 @@ static inline unsigned int max_hw_blocks(struct f2fs_sb_info *sbi) 
	struct request_queue *q = bdev_get_queue(bdev);

	struct request_queue *q = bdev_get_queue(bdev);

	return SECTOR_TO_BLOCK(sbi, queue_max_sectors(q));

	return SECTOR_TO_BLOCK(sbi, queue_max_sectors(q));

}

}



/*

 * It is very important to gather dirty pages and write at once, so that we can

 * submit a big bio without interfering other data writes.

 * By default, 512 pages for directory data,

 * 512 pages (2MB) * 3 for three types of nodes, and

 * max_bio_blocks for meta are set.

 */

static inline int nr_pages_to_skip(struct f2fs_sb_info *sbi, int type)

{

	if (type == DATA)

		return sbi->blocks_per_seg;

	else if (type == NODE)

		return 3 * sbi->blocks_per_seg;

	else if (type == META)

		return MAX_BIO_BLOCKS(max_hw_blocks(sbi));

	else

		return 0;

}