Re: [PATCH v2] ext4: lost matching-pair of trace in ext4_truncate

[Ritesh Harjani <riteshh@linux.ibm.com>]

On 7/1/20 2:00 PM, zhengliang wrote:
> It should call trace exit in all return path for ext4_truncate.
> 
> v2:
> It shoule call trace exit in all return path, and add "out_trace" label to avoid the
> multiple copies of the cleanup code in each error case.

v2 description should generally go below three dashed line so that
it need not become part of commit msg.


> 
> Signed-off-by: zhengliang <zhengliang6@huawei.com>

LGTM, feel free to add
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>


> ---
>   fs/ext4/inode.c | 17 +++++++++--------
>   1 file changed, 9 insertions(+), 8 deletions(-)
> 
> diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
> index 10dd470876b3..6187c8880c02 100644
> --- a/fs/ext4/inode.c
> +++ b/fs/ext4/inode.c
> @@ -4163,7 +4163,7 @@ int ext4_truncate(struct inode *inode)
>   	trace_ext4_truncate_enter(inode);
> 
>   	if (!ext4_can_truncate(inode))
> -		return 0;
> +		goto out_trace;
> 
>   	if (inode->i_size == 0 && !test_opt(inode->i_sb, NO_AUTO_DA_ALLOC))
>   		ext4_set_inode_state(inode, EXT4_STATE_DA_ALLOC_CLOSE);
> @@ -4172,16 +4172,14 @@ int ext4_truncate(struct inode *inode)
>   		int has_inline = 1;
> 
>   		err = ext4_inline_data_truncate(inode, &has_inline);
> -		if (err)
> -			return err;
> -		if (has_inline)
> -			return 0;
> +		if (err || has_inline)
> +			goto out_trace;
>   	}
> 
>   	/* If we zero-out tail of the page, we have to create jinode for jbd2 */
>   	if (inode->i_size & (inode->i_sb->s_blocksize - 1)) {
>   		if (ext4_inode_attach_jinode(inode) < 0)
> -			return 0;
> +			goto out_trace;
>   	}
> 
>   	if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
> @@ -4190,8 +4188,10 @@ int ext4_truncate(struct inode *inode)
>   		credits = ext4_blocks_for_truncate(inode);
> 
>   	handle = ext4_journal_start(inode, EXT4_HT_TRUNCATE, credits);
> -	if (IS_ERR(handle))
> -		return PTR_ERR(handle);
> +	if (IS_ERR(handle)) {
> +		err = PTR_ERR(handle);
> +		goto out_trace;
> +	}
> 
>   	if (inode->i_size & (inode->i_sb->s_blocksize - 1))
>   		ext4_block_truncate_page(handle, mapping, inode->i_size);
> @@ -4242,6 +4242,7 @@ int ext4_truncate(struct inode *inode)
>   		err = err2;
>   	ext4_journal_stop(handle);
> 
> +out_trace:
>   	trace_ext4_truncate_exit(inode);
>   	return err;
>   }
>