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Subject: Re: [PATCH] f2fs: change the codes of checking CP_CRC_RECOVERY_FLAG
 to macro
To: Jaegeuk Kim <jaegeuk@kernel.org>
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From: Yunlong Song <yunlong.song@huawei.com>
Message-ID: <58B13C05.50900@huawei.com>
Date: Sat, 25 Feb 2017 16:10:45 +0800
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On 2017/2/25 2:12, Jaegeuk Kim wrote:

> 
> This is to handle only one case in which:
> 
> 1. uses old kernel without this flag,
> 2. calls fsync and gets sudden power-cut,
> 3. updates new kernel having this flag before mount.
> 
> Then, if we do not check this flag at mount time, we will lose the last fsync'ed
> node blocks.
> 

So I just send a v2 patch to only change to macro in fill_node_footer_blkaddr and
allocate_segment_by_default, these two functions are called frequently, so it is
better to use macro code. And I remain the original checking code in is_recoverable_dnode,
this function is called only once after mount, it's OK.

-- 
Thanks,
Yunlong Song