Hi Yu,
On 10/24/2013 04:21 PM, Chao Yu wrote:
> Previously, check_block_count check valid_map with bit data type in common
> scenario that sit has all ones or zeros bitmap, it makes low mount
> performance.
> So let's check the special bitmap with integer data type instead of the bit
> one.
>
> v2:
> use find_next_bit_le/find_next_zero_bit_le for better performance and
> readable as Jaegeuk suggested.
If so, how about using find_first_{zero_}bit_le instead? It's more neat.
Regards,
Gu
>
> Suggested-by: Jaegeuk Kim <jaegeuk....@samsung.com>
> Signed-off-by: Tan Shu <shu....@samsung.com>
> Signed-off-by: Yu Chao <chao2...@samsung.com>
> ---
> fs/f2fs/segment.h | 17 +++++++++++++++++
> 1 file changed, 17 insertions(+)
>
> diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h
> index 7f94d78..d25b6af 100644
> --- a/fs/f2fs/segment.h
> +++ b/fs/f2fs/segment.h
> @@ -552,6 +552,23 @@ static inline void check_block_count(struct f2fs_sb_info
> *sbi,
> /* check boundary of a given segment number */
> BUG_ON(segno > end_segno);
>
> + /* check all ones or zeros valid_map */
> + if (GET_SIT_VBLOCKS(raw_sit) == 0) {
> + int pos = find_next_bit_le(&raw_sit->valid_map,
> + sbi->blocks_per_seg,
> + 0);
> + if (pos != sbi->blocks_per_seg)
> + BUG();
> + return;
> + } else if (GET_SIT_VBLOCKS(raw_sit) == sbi->blocks_per_seg) {
> + int pos = find_next_zero_bit_le(&raw_sit->valid_map,
> + sbi->blocks_per_seg,
> + 0);
> + if (pos != sbi->blocks_per_seg)
> + BUG();
> + return;
> + }
> +
> /* check bitmap with valid block count */
> for (i = 0; i < sbi->blocks_per_seg; i++)
> if (f2fs_test_bit(i, raw_sit->valid_map))
--
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