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Message-ID: <2f100a4a-592d-f098-b204-efeef58341ee@kernel.org>
Date:   Mon, 12 Dec 2022 22:34:33 +0800
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To:     Yangtao Li <frank.li@vivo.com>, jaegeuk@kernel.org
Cc:     linux-f2fs-devel@lists.sourceforge.net,
        linux-kernel@vger.kernel.org
References: <974f5013-b6af-a39e-0b0f-2ce86253eaeb@kernel.org>
 <20221212141429.6329-1-frank.li@vivo.com>
From:   Chao Yu <chao@kernel.org>
Subject: Re: [PATCH v2] f2fs: don't call f2fs_issue_discard_timeout() when
 discard_cmd_cnt is 0 in f2fs_put_super()
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On 2022/12/12 22:14, Yangtao Li wrote:
> Hi Chao,
> 
>> The difference here is, if we use f2fs_realtime_discard_enable() in
>> f2fs_put_super(), we will only write checkpoint w/ CP_TRIMMED flag
>> when discard option is enable and device supports discard.
> 
>> But actually, if discard option is disabled, we still needs to give
>> put_super() a chance to write checkpoint w/ CP_TRIMMED flag.
> 
> Why do we still have to set the CP_TRIMMED flag when the discard opt is not set.
> Did I miss something?

Hi Yangtao,

I guess it's up to scenario. e.g.

mount w/ nodiscard and use FITRIM to trigger in-batch discard,
if we set CP_TRIMMED flag during umount, next time, after mount
w/ discard, it doesn't to issue redundant discard.

Thanks,

> 
> Thx,
> Yangtao