From: jing zhang <zj.barak@gmail.com>
Subject: Re: [PATCH] ext4: group cache is added in ext4_mb_discard_preallocations()
Date: Wed, 7 Apr 2010 20:58:36 +0800
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Cc: Andreas Dilger <adilger@sun.com>,
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To: tytso@mit.edu
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2010/4/7, tytso@mit.edu <tytso@mit.edu>:
> On Thu, Apr 01, 2010 at 08:34:41PM +0800, jing zhang wrote:
>>
>> --- linux-2.6.32/fs/ext4/mballoc.c	2009-12-03 11:51:22.000000000 +0800
>> +++ ext4_mm_leak/mballoc-14.c	2010-04-01 20:35:58.000000000 +0800
>> @@ -4299,7 +4299,7 @@ repeat:
>>  		}
>>  	} else {
>>  		freed  = ext4_mb_discard_preallocations(sb, ac->ac_o_ex.fe_len);
>> -		if (freed)
>> +		if (freed && freed >= ac->ac_o_ex.fe_len)
>>  			goto repeat;
>>  		*errp = -ENOSPC;
>>  		ac->ac_b_ex.fe_len = 0;
>
> This is just wrong.
>
> Since you didn't give a justification, I'm not sure why you think it
> is correct.
>

Though freed, is the amount freed bigger than needed?
If not, it seems unnecessary to repeat.

      - zj