For consecutive large hole mapping across {d,id,did}nodes , we don't
need to call f2fs_map_blocks() to check one hole block per one time,
instead, we can use map.m_next_pgofs as a hint of next potential valid
block, so that we can skip calling f2fs_map_blocks the range of
[cur_pgofs + 1, .m_next_pgofs).1) regular case touch /mnt/f2fs/file truncate -s $((1024*1024*1024)) /mnt/f2fs/file time dd if=/mnt/f2fs/file of=/dev/null bs=1M count=1024 Before: real 0m0.706s user 0m0.000s sys 0m0.706s After: real 0m0.620s user 0m0.008s sys 0m0.611s 2) large folio case touch /mnt/f2fs/file truncate -s $((1024*1024*1024)) /mnt/f2fs/file f2fs_io setflags immutable /mnt/f2fs/file sync echo 3 > /proc/sys/vm/drop_caches time dd if=/mnt/f2fs/file of=/dev/null bs=1M count=1024 Before: real 0m0.438s user 0m0.004s sys 0m0.433s After: real 0m0.368s user 0m0.004s sys 0m0.364s Signed-off-by: Chao Yu <[email protected]> --- fs/f2fs/data.c | 21 +++++++++++++++------ 1 file changed, 15 insertions(+), 6 deletions(-) diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c index a2c4769d0ae1..5b0642cd27ff 100644 --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -2176,10 +2176,13 @@ static int f2fs_read_single_page(struct inode *inode, struct folio *folio, /* * Map blocks using the previous result first. */ - if ((map->m_flags & F2FS_MAP_MAPPED) && - block_in_file > map->m_lblk && + if (map->m_flags & F2FS_MAP_MAPPED) { + if (block_in_file > map->m_lblk && block_in_file < (map->m_lblk + map->m_len)) + goto got_it; + } else if (block_in_file < *map->m_next_pgofs) { goto got_it; + } /* * Then do more f2fs_map_blocks() calls until we are @@ -2454,7 +2457,7 @@ static int f2fs_read_data_large_folio(struct inode *inode, struct bio *bio = NULL; sector_t last_block_in_bio = 0; struct f2fs_map_blocks map = {0, }; - pgoff_t index, offset; + pgoff_t index, offset, next_pgofs = 0; unsigned max_nr_pages = rac ? readahead_count(rac) : folio_nr_pages(folio); unsigned nrpages; @@ -2487,16 +2490,21 @@ static int f2fs_read_data_large_folio(struct inode *inode, /* * Map blocks using the previous result first. */ - if ((map.m_flags & F2FS_MAP_MAPPED) && - index > map.m_lblk && + if (map.m_flags & F2FS_MAP_MAPPED) { + if (index > map.m_lblk && index < (map.m_lblk + map.m_len)) + goto got_it; + } else if (index < next_pgofs) { + /* hole case */ goto got_it; + } /* * Then do more f2fs_map_blocks() calls until we are * done with this page. */ memset(&map, 0, sizeof(map)); + map.m_next_pgofs = &next_pgofs; map.m_seg_type = NO_CHECK_TYPE; map.m_lblk = index; map.m_len = max_nr_pages; @@ -2617,6 +2625,7 @@ static int f2fs_mpage_readpages(struct inode *inode, pgoff_t nc_cluster_idx = NULL_CLUSTER; pgoff_t index; #endif + pgoff_t next_pgofs = 0; unsigned nr_pages = rac ? readahead_count(rac) : 1; struct address_space *mapping = rac ? rac->mapping : folio->mapping; unsigned max_nr_pages = nr_pages; @@ -2637,7 +2646,7 @@ static int f2fs_mpage_readpages(struct inode *inode, map.m_lblk = 0; map.m_len = 0; map.m_flags = 0; - map.m_next_pgofs = NULL; + map.m_next_pgofs = &next_pgofs; map.m_next_extent = NULL; map.m_seg_type = NO_CHECK_TYPE; map.m_may_create = false; -- 2.40.1 _______________________________________________ Linux-f2fs-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel
