On 2017/2/23 17:18, Hou Pengyang wrote:
> proc A:                      proc B:
> - writeback_sb_inodes
> - __writeback_single_inode   
> - do_writepages
> - f2fs_write_node_pages       
> - f2fs_balance_fs_bg         - write_checkpoint
> - build_free_nids            - flush_nat_entries
> - __build_free_nids          - __flush_nat_entry_set
> - ra_meta_pages              - get_next_nat_page
> - current_nat_addr           - set_to_next_nat
> [do nat_bitmap checking]     - f2fs_change_bit

Both flows were protected by nat_tree_lock, so we don't need to worry about such
case?

Thanks,

> 
> For proc A, nat_bitmap and nat_bitmap_mir would be compared without lock_op 
> and 
> nm_i->nat_tree_lock, while proc B is changing nat_bitmap/nat_bitmap_ver in cp.
> 
> So it is normal for nat_bitmap/nat_bitmap diffrence under such scenario.
> 
> This patch fix this by removing the monitoring point.
> 
> [Fix: 599a09b f2fs: check in-memory nat version bitmap]
> Signed-off-by: Hou Pengyang <houpengy...@huawei.com>
> ---
>  fs/f2fs/node.h | 6 ------
>  1 file changed, 6 deletions(-)
> 
> diff --git a/fs/f2fs/node.h b/fs/f2fs/node.h
> index d3d2893..3fc9c4b 100644
> --- a/fs/f2fs/node.h
> +++ b/fs/f2fs/node.h
> @@ -209,12 +209,6 @@ static inline pgoff_t current_nat_addr(struct 
> f2fs_sb_info *sbi, nid_t start)
>               (seg_off << sbi->log_blocks_per_seg << 1) +
>               (block_off & (sbi->blocks_per_seg - 1)));
>  
> -#ifdef CONFIG_F2FS_CHECK_FS
> -     if (f2fs_test_bit(block_off, nm_i->nat_bitmap) !=
> -                     f2fs_test_bit(block_off, nm_i->nat_bitmap_mir))
> -             f2fs_bug_on(sbi, 1);
> -#endif
> -
>       if (f2fs_test_bit(block_off, nm_i->nat_bitmap))
>               block_addr += sbi->blocks_per_seg;
>  
> 


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