3.16.54-rc1 review patch. If anyone has any objections, please let me know.
------------------ From: Dongho Sim <[email protected]> commit 33be828ada7274ebcade2001f16e5b4e33a4636e upstream. There are redundant lines in allocate_data_block. In this function, we call refresh_sit_entry with old seg and old curseg. After that, we call locate_dirty_segment with old curseg. But, the new address is always allocated from old curseg and we call locate_dirty_segment with old curseg in refresh_sit_entry. So, we do not need to call locate_dirty_segment with old curseg again. We've discussed like below: Jaegeuk said: "When considering SSR, we need to take care of the following scenario. - old segno : X - new address : Z - old curseg : Y This means, a new block is supposed to be written to Z from X. And Z is newly allocated in the same path from Y. In that case, we should trigger locate_dirty_segment for Y, since it was a current_segment and can be dirty owing to SSR. But that was not included in the dirty list." Changman said: "We already choosed old curseg(Y) and then we allocate new address(Z) from old curseg(Y). After that we call refresh_sit_entry(old address, new address). In the funcation, we call locate_dirty_segment with old seg and old curseg. So calling locate_dirty_segment after refresh_sit_entry again is redundant." Jaegeuk said: "Right. The new address is always allocated from old_curseg." Reviewed-by: Chao Yu <[email protected]> Signed-off-by: Dongho Sim <[email protected]> Signed-off-by: Jaegeuk Kim <[email protected]> Signed-off-by: Ben Hutchings <[email protected]> --- fs/f2fs/segment.c | 3 --- 1 file changed, 3 deletions(-) --- a/fs/f2fs/segment.c +++ b/fs/f2fs/segment.c @@ -969,14 +969,12 @@ void allocate_data_block(struct f2fs_sb_ { struct sit_info *sit_i = SIT_I(sbi); struct curseg_info *curseg; - unsigned int old_cursegno; curseg = CURSEG_I(sbi, type); mutex_lock(&curseg->curseg_mutex); *new_blkaddr = NEXT_FREE_BLKADDR(sbi, curseg); - old_cursegno = curseg->segno; /* * __add_sum_entry should be resided under the curseg_mutex @@ -997,7 +995,6 @@ void allocate_data_block(struct f2fs_sb_ * since SSR needs latest valid block information. */ refresh_sit_entry(sbi, old_blkaddr, *new_blkaddr); - locate_dirty_segment(sbi, old_cursegno); mutex_unlock(&sit_i->sentry_lock);
