2015-12-17 05:21:46

by Fan Li

Subject: [f2fs-dev] [PATCH] f2fs: optimize the flow of f2fs_map_blocks

check map->m_len right after it changes to avoid excess call
to update dnode_of_data.

Signed-off-by: Fan li <[email protected]>
---
fs/f2fs/data.c | 69 +++++++++++++++++++++++++++++---------------------------
1 file changed, 36 insertions(+), 33 deletions(-)

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 90a2ffe..8fa4560 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -573,6 +573,7 @@ int f2fs_map_blocks(struct inode *inode, struct f2fs_map_blocks *map,
int err = 0, ofs = 1;
struct extent_info ei;
bool allocated = false;
+ block_t blkaddr;

map->m_len = 0;
map->m_flags = 0;
@@ -636,6 +637,9 @@ int f2fs_map_blocks(struct inode *inode, struct f2fs_map_blocks *map,
pgofs++;

get_next:
+ if (map->m_len >= maxblocks)
+ goto sync_out;
+
if (dn.ofs_in_node >= end_offset) {
if (allocated)
sync_inode_page(&dn);
@@ -653,44 +657,43 @@ get_next:
end_offset = ADDRS_PER_PAGE(dn.node_page, F2FS_I(inode));
}

- if (maxblocks > map->m_len) {
- block_t blkaddr = datablock_addr(dn.node_page, dn.ofs_in_node);
+ blkaddr = datablock_addr(dn.node_page, dn.ofs_in_node);

- if (blkaddr == NEW_ADDR || blkaddr == NULL_ADDR) {
- if (create) {
- if (unlikely(f2fs_cp_error(sbi))) {
- err = -EIO;
- goto sync_out;
- }
- err = __allocate_data_block(&dn);
- if (err)
- goto sync_out;
- allocated = true;
- map->m_flags |= F2FS_MAP_NEW;
- blkaddr = dn.data_blkaddr;
- } else {
- /*
- * we only merge preallocated unwritten blocks
- * for fiemap.
- */
- if (flag != F2FS_GET_BLOCK_FIEMAP ||
- blkaddr != NEW_ADDR)
- goto sync_out;
+ if (blkaddr == NEW_ADDR || blkaddr == NULL_ADDR) {
+ if (create) {
+ if (unlikely(f2fs_cp_error(sbi))) {
+ err = -EIO;
+ goto sync_out;
}
+ err = __allocate_data_block(&dn);
+ if (err)
+ goto sync_out;
+ allocated = true;
+ map->m_flags |= F2FS_MAP_NEW;
+ blkaddr = dn.data_blkaddr;
+ } else {
+ /*
+ * we only merge preallocated unwritten blocks
+ * for fiemap.
+ */
+ if (flag != F2FS_GET_BLOCK_FIEMAP ||
+ blkaddr != NEW_ADDR)
+ goto sync_out;
}
+ }

- /* Give more consecutive addresses for the readahead */
- if ((map->m_pblk != NEW_ADDR &&
- blkaddr == (map->m_pblk + ofs)) ||
- (map->m_pblk == NEW_ADDR &&
- blkaddr == NEW_ADDR)) {
- ofs++;
- dn.ofs_in_node++;
- pgofs++;
- map->m_len++;
- goto get_next;
- }
+ /* Give more consecutive addresses for the readahead */
+ if ((map->m_pblk != NEW_ADDR &&
+ blkaddr == (map->m_pblk + ofs)) ||
+ (map->m_pblk == NEW_ADDR &&
+ blkaddr == NEW_ADDR)) {
+ ofs++;
+ dn.ofs_in_node++;
+ pgofs++;
+ map->m_len++;
+ goto get_next;
}
+
sync_out:
if (allocated)
sync_inode_page(&dn);
--
1.7.9.5

2015-12-17 09:19:20

by Chao Yu

Subject: RE: [f2fs-dev] [PATCH] f2fs: optimize the flow of f2fs_map_blocks

> -----Original Message-----
> From: Fan Li [mailto:[email protected]]
> Sent: Thursday, December 17, 2015 1:21 PM
> To: 'Jaegeuk Kim'
> Cc: [email protected]; [email protected]
> Subject: [f2fs-dev] [PATCH] f2fs: optimize the flow of f2fs_map_blocks
>
> check map->m_len right after it changes to avoid excess call
> to update dnode_of_data.
>
> Signed-off-by: Fan li <[email protected]>

Reviewed-by: Chao Yu <[email protected]>