f2fs: issue more large discard command
o Changes from v1
Use find_next(_zero)_bit suggested by jg.kim
When f2fs issues discard command, if segment is contiguous,
let's issue more large segment to gather adjacent segments.
** blktrace **
179,1 0 5859 42.619023770 971 C D 131072 + 2097152 [0]
179,1 0 33665 108.840475468 971 C D 2228224 + 2494464 [0]
179,1 0 33671 109.131616427 971 C D 14909440 + 344064 [0]
179,1 0 33677 109.137100677 971 C D 15261696 + 4096 [0]
Signed-off-by: Changman Lee <[email protected]>
Signed-off-by: Jaegeuk Kim <[email protected]>
diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index 86dc289..fa284d3 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -139,27 +139,33 @@
void clear_prefree_segments(struct f2fs_sb_info *sbi)
{
struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
- unsigned int segno = -1;
+ unsigned long *prefree_map = dirty_i->dirty_segmap[PRE];
unsigned int total_segs = TOTAL_SEGS(sbi);
+ unsigned int start = 0, end = -1;
mutex_lock(&dirty_i->seglist_lock);
+
while (1) {
- segno = find_next_bit(dirty_i->dirty_segmap[PRE], total_segs,
- segno + 1);
- if (segno >= total_segs)
+ int i;
+ start = find_next_bit(prefree_map, total_segs, end + 1);
+ if (start >= total_segs)
break;
+ end = find_next_zero_bit(prefree_map, total_segs, start + 1);
- if (test_and_clear_bit(segno, dirty_i->dirty_segmap[PRE]))
- dirty_i->nr_dirty[PRE]--;
+ for (i = start; i < end; i++)
+ clear_bit(i, prefree_map);
- /* Let's use trim */
- if (test_opt(sbi, DISCARD))
- blkdev_issue_discard(sbi->sb->s_bdev,
- START_BLOCK(sbi, segno) <<
- sbi->log_sectors_per_block,
- 1 << (sbi->log_sectors_per_block +
- sbi->log_blocks_per_seg),
- GFP_NOFS, 0);
+ dirty_i->nr_dirty[PRE] -= end - start;
+
+ if (!test_opt(sbi, DISCARD))
+ continue;
+
+ blkdev_issue_discard(sbi->sb->s_bdev,
+ START_BLOCK(sbi, start) <<
+ sbi->log_sectors_per_block,
+ (1 << (sbi->log_sectors_per_block +
+ sbi->log_blocks_per_seg)) * (end - start),
+ GFP_NOFS, 0);
}
mutex_unlock(&dirty_i->seglist_lock);
}
