Re: [PATCH v21 01/13] xfs: Return from xfs_attr_set_iter if there are no more rmtblks to process

[Allison Henderson <allison.henderson@oracle.com>]

On 7/8/21 9:05 PM, Darrick J. Wong wrote:
> On Wed, Jul 07, 2021 at 03:20:59PM -0700, Allison Henderson wrote:
>> During an attr rename operation, blocks are saved for later removal
>> as rmtblkno2. The rmtblkno is used in the case of needing to alloc
>> more blocks if not enough were available.  However, in the case
>> that neither rmtblkno or rmtblkno2 are set, we can return as soon
>> as xfs_attr_node_addname completes, rather than rolling the transaction
>> with an -EAGAIN return.  This extra loop does not hurt anything right
>> now, but it will be a problem later when we get into log items because
>> we end up with an empty log transaction.  So, add a simple check to
>> cut out the unneeded iteration.
>>
>> Signed-off-by: Allison Henderson <allison.henderson@oracle.com>
>> ---
>>   fs/xfs/libxfs/xfs_attr.c | 7 +++++++
>>   1 file changed, 7 insertions(+)
>>
>> diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c
>> index 611dc67..5e81389 100644
>> --- a/fs/xfs/libxfs/xfs_attr.c
>> +++ b/fs/xfs/libxfs/xfs_attr.c
>> @@ -409,6 +409,13 @@ xfs_attr_set_iter(
>>   			if (error)
>>   				return error;
>>   
>> +			/*
>> +			 * If addname was successful, and we dont need to alloc
>> +			 * or remove anymore blks, we're done.
>> +			 */
>> +			if (!args->rmtblkno && !args->rmtblkno2)
>> +				return error;
> 
> Is there actually an error to return here, or could this be a 'return 0;' ?
> 
> --D
Error is zero here, I just try to make the code consistent looking.  It 
can be a hard zero if folk prefer.

Allison

> 
>> +
>>   			dac->dela_state = XFS_DAS_FOUND_NBLK;
>>   		}
>>   		return -EAGAIN;
>> -- 
>> 2.7.4
>>