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Message-ID: <974f5013-b6af-a39e-0b0f-2ce86253eaeb@kernel.org>
Date:   Mon, 12 Dec 2022 21:50:08 +0800
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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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To:     Yangtao Li <frank.li@vivo.com>, jaegeuk@kernel.org
Cc:     linux-f2fs-devel@lists.sourceforge.net,
        linux-kernel@vger.kernel.org
References: <3f2c81f8-7946-d2e0-8768-6f0b03282944@kernel.org>
 <20221212130554.79049-1-frank.li@vivo.com>
From:   Chao Yu <chao@kernel.org>
In-Reply-To: <20221212130554.79049-1-frank.li@vivo.com>
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On 2022/12/12 21:05, Yangtao Li wrote:
> Hi,
> 
>> static inline bool f2fs_realtime_discard_enable(struct f2fs_sb_info *sbi) {
>> 	return (test_opt(sbi, DISCARD) && f2fs_hw_support_discard(sbi)) ||
>> 					f2fs_hw_should_discard(sbi);
>> }
> 
>> It looks the logic is changed?
> 
> For a storage device that does not support discard, and we have not actually
> issued any discard command. I don't think it is necessary and f2fs should not
> be equipped with trim markers.

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.

Thanks,

> 
> Thx,
> Yangtao