Re: [RFC] block: remove never-modified global variable

[Brian Norris <computersforpeace@gmail.com>]

On Tue, May 19, 2015 at 10:34:56AM +0300, Boaz Harrosh wrote:
> On 05/19/2015 10:19 AM, Boaz Harrosh wrote:
> <>
> > But specially now that you are unconditionally printing it. It is better
> > to just combine the two statements. See suggested patch below:
> > 
> 
> Actually we can even do better:
> 
> diff --git a/block/partitions/check.c b/block/partitions/check.c
> index 513c601..9bea23d 100644
> --- a/block/partitions/check.c
> +++ b/block/partitions/check.c
> @@ -160,35 +160,31 @@ check_partition(struct gendisk *hd, struct block_device *bdev)
>  
>  	i = res = err = 0;
>  	while (!res && check_part[i]) {
>  		memset(state->parts, 0, state->limit * sizeof(state->parts[0]));
>  		res = check_part[i++](state);
>  		if (res < 0) {
>  			/* We have hit an I/O error which we don't report now.
>  		 	* But record it, and let the others do their job.
>  		 	*/
>  			err = res;
>  			res = 0;
>  		}
>  
>  	}
> 
> boaz> When we exit the loop res can only be (res >= 0)
> 
>  	if (res > 0) {
>  		printk(KERN_INFO "%s", state->pp_buf);
>  
>  		free_page((unsigned long)state->pp_buf);
>  		return state;
> 
> boaz> When bigger we exit here
> 
>  	}
>  	if (state->access_beyond_eod)
>  		err = -ENOSPC;
> 
> boaz> So by this stage res can only be == 0. So we should just do:
> 
>  	if (err)
> 	/* The partition is unrecognized. So report I/O errors if there were any */
> -		res = err;

^^ You don't want to kill this line, since we still return ERR_PRT(res).
But otherwise, I think you're right.

> -	if (res) {
> -		strlcat(state->pp_buf,
> -			" unable to read partition table\n", PAGE_SIZE);
> -		printk(KERN_INFO "%s", state->pp_buf);
> -	}
> +		printk(KERN_INFO "%s unable to read partition table\n",
> +		       state->pp_buf);
>  
>  	free_page((unsigned long)state->pp_buf);
>  	free_partitions(state);
>  	return ERR_PTR(res);
>  }
> 
> ----
> Here is a proper diff:

I can send out a full patch, squashing my original + your fixup + my
fixup, if that sounds OK.

Brian