From 79344efb93a26378a91193bed133cee42162cd81 Mon Sep 17 00:00:00 2001 From: Jaegeuk Kim Date: Fri, 6 May 2016 16:19:43 -0700 Subject: [PATCH] f2fs: read node blocks ahead when truncating blocks This patch enables reading node blocks in advance when truncating large data blocks. > time rm $MNT/testfile (500GB) after drop_cachees Before : 9.422 s After : 4.821 s Reported-by: Stephen Bates Signed-off-by: Jaegeuk Kim --- fs/f2fs/file.c | 2 +- fs/f2fs/node.c | 52 +++++++++++++++++++++++++++----------------------- 2 files changed, 29 insertions(+), 25 deletions(-) diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c index fb8cc27d4cc6..314612997721 100644 --- a/fs/f2fs/file.c +++ b/fs/f2fs/file.c @@ -584,7 +584,7 @@ int truncate_blocks(struct inode *inode, u64 from, bool lock) } set_new_dnode(&dn, inode, ipage, NULL, 0); - err = get_dnode_of_data(&dn, free_from, LOOKUP_NODE); + err = get_dnode_of_data(&dn, free_from, LOOKUP_NODE_RA); if (err) { if (err == -ENOENT) goto free_next; diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c index 264abe08bafb..cda7c7ccd4c8 100644 --- a/fs/f2fs/node.c +++ b/fs/f2fs/node.c @@ -407,6 +407,29 @@ cache: up_write(&nm_i->nat_tree_lock); } +/* + * readahead MAX_RA_NODE number of node pages. + */ +static void ra_node_pages(struct page *parent, int start, int n) +{ + struct f2fs_sb_info *sbi = F2FS_P_SB(parent); + struct blk_plug plug; + int i, end; + nid_t nid; + + blk_start_plug(&plug); + + /* Then, try readahead for siblings of the desired node */ + end = start + n; + end = min(end, NIDS_PER_BLOCK); + for (i = start; i < end; i++) { + nid = get_nid(parent, i, false); + ra_node_page(sbi, nid); + } + + blk_finish_plug(&plug); +} + pgoff_t get_next_page_offset(struct dnode_of_data *dn, pgoff_t pgofs) { const long direct_index = ADDRS_PER_INODE(dn->inode); @@ -707,6 +730,8 @@ static int truncate_nodes(struct dnode_of_data *dn, unsigned int nofs, return PTR_ERR(page); } + ra_node_pages(page, ofs, NIDS_PER_BLOCK); + rn = F2FS_NODE(page); if (depth < 3) { for (i = ofs; i < NIDS_PER_BLOCK; i++, freed++) { @@ -784,6 +809,8 @@ static int truncate_partial_nodes(struct dnode_of_data *dn, nid[i + 1] = get_nid(pages[i], offset[i + 1], false); } + ra_node_pages(pages[idx], offset[idx + 1], NIDS_PER_BLOCK); + /* free direct nodes linked to a partial indirect node */ for (i = offset[idx + 1]; i < NIDS_PER_BLOCK; i++) { child_nid = get_nid(pages[idx], i, false); @@ -1095,29 +1122,6 @@ void ra_node_page(struct f2fs_sb_info *sbi, nid_t nid) f2fs_put_page(apage, err ? 1 : 0); } -/* - * readahead MAX_RA_NODE number of node pages. - */ -static void ra_node_pages(struct page *parent, int start) -{ - struct f2fs_sb_info *sbi = F2FS_P_SB(parent); - struct blk_plug plug; - int i, end; - nid_t nid; - - blk_start_plug(&plug); - - /* Then, try readahead for siblings of the desired node */ - end = start + MAX_RA_NODE; - end = min(end, NIDS_PER_BLOCK); - for (i = start; i < end; i++) { - nid = get_nid(parent, i, false); - ra_node_page(sbi, nid); - } - - blk_finish_plug(&plug); -} - static struct page *__get_node_page(struct f2fs_sb_info *sbi, pgoff_t nid, struct page *parent, int start) { @@ -1141,7 +1145,7 @@ repeat: } if (parent) - ra_node_pages(parent, start + 1); + ra_node_pages(parent, start + 1, MAX_RA_NODE); lock_page(page); -- 2.20.1