[Crash-utility] [PATCH 1/2] tree: no need to bail out on tree corruption, skip the node and move on instead

[Dave Anderson]

Hi Daniel,

If the tree is corrupted, I would think that you would want to know the
specifics, i.e., aside from the somewhat cryptic readmem() error message.

Perhaps it would be worth printing a more meaningful error message, 
something like: 

  tree: rb_node: <address>: corrupt rb_left pointer: <address>

That way you could do the 2 readmem() calls w/RETURN_ON_ERROR|QUIET, and
just have the concise error message.

Thanks,
  Dave

----- Original Message -----
> ---
>  tools.c | 23 ++++++++++++-----------
>  1 file changed, 12 insertions(+), 11 deletions(-)
> 
> diff --git a/tools.c b/tools.c
> index 186b703463a5..992f4776281a 100644
> --- a/tools.c
> +++ b/tools.c
> @@ -4374,8 +4374,8 @@ rbtree_iteration(ulong node_p, struct tree_data *td,
> char *pos)
>  {
>  	int i;
>  	uint print_radix;
> -	ulong struct_p, left_p, right_p;
> -	char left_pos[BUFSIZE], right_pos[BUFSIZE];
> +	ulong struct_p, new_p;
> +	char new_pos[BUFSIZE];
>  	static struct req_entry **e;
>  
>  	if (!node_p)
> @@ -4430,16 +4430,17 @@ rbtree_iteration(ulong node_p, struct tree_data *td,
> char *pos)
>  		}
>  	}
>  
> -	readmem(node_p+OFFSET(rb_node_rb_left), KVADDR, &left_p,
> -		sizeof(void *), "rb_node rb_left", FAULT_ON_ERROR);
> -	readmem(node_p+OFFSET(rb_node_rb_right), KVADDR, &right_p,
> -		sizeof(void *), "rb_node rb_right", FAULT_ON_ERROR);
> -
> -	sprintf(left_pos, "%s/l", pos);
> -	sprintf(right_pos, "%s/r", pos);
> +	if (	readmem(node_p+OFFSET(rb_node_rb_left), KVADDR, &new_p,
> +			sizeof(void *), "rb_node rb_left", RETURN_ON_ERROR)) {
> +		sprintf(new_pos, "%s/l", pos);
> +		rbtree_iteration(new_p, td, new_pos);
> +	}
>  
> -	rbtree_iteration(left_p, td, left_pos);
> -	rbtree_iteration(right_p, td, right_pos);
> +	if (	readmem(node_p+OFFSET(rb_node_rb_right), KVADDR, &new_p,
> +			sizeof(void *), "rb_node rb_right", RETURN_ON_ERROR)) {
> +		sprintf(new_pos, "%s/r", pos);
> +		rbtree_iteration(new_p, td, new_pos);
> +	}
>  }
>  
>  void
> --
> 2.16.2
> 
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