[PATCH 3/4] xfs: combine xfs_rtmodify_summary and xfs_rtget_summary

[Eric Sandeen]

On 8/22/14, 8:19 AM, Brian Foster wrote:
> On Thu, Aug 21, 2014 at 08:00:45PM -0500, Eric Sandeen wrote:

...

>> @@ -480,15 +484,40 @@ xfs_rtmodify_summary(
>>  		}
>>  	}
>>  	/*
>> -	 * Point to the summary information, modify and log it.
>> +	 * Point to the summary information, modify/log it, and/or copy it out.
>>  	 */
>>  	sp = XFS_SUMPTR(mp, bp, so);
>> -	*sp += delta;
>> -	xfs_trans_log_buf(tp, bp, (uint)((char *)sp - (char *)bp->b_addr),
>> -		(uint)((char *)sp - (char *)bp->b_addr + sizeof(*sp) - 1));
>> +	if (delta) {
>> +		uint first = (uint)((char *)sp - (char *)bp->b_addr);
>> +
>> +		*sp += delta;
>> +		xfs_trans_log_buf(tp, bp, first, first + sizeof(*sp) - 1);
>> +	}
>> +	if (sum) {
>> +		/*
>> +		 * Drop the buffer if we're not asked to remember it.
>> +		 */
>> +		if (!rbpp)
>> +			xfs_trans_brelse(tp, bp);
> 
> This introduces some potentially weird circumstances (e.g., acquire,
> log, release of a buffer), but I think it's resolved by the next patch.
> 
> Reviewed-by: Brian Foster <bfoster at redhat.com>

does it introduce it, or just highlight it?  I thought it was weird too,
but I think it existed before; that's what prompted me to go looking at
callers and drop the rbpp checks, FWIW.

-Eric