Subject: Re: [PATCH] f2fs: clear get_ssr_cost
To: Yunlong Song <yunlong.song@huawei.com>, <jaegeuk@kernel.org>,
        <chao@kernel.org>, <yunlong.song@icloud.com>
CC: <miaoxie@huawei.com>, <bintian.wang@huawei.com>,
        <linux-fsdevel@vger.kernel.org>,
        <linux-f2fs-devel@lists.sourceforge.net>,
        <linux-kernel@vger.kernel.org>
References: <1504268075-81858-1-git-send-email-yunlong.song@huawei.com>
From: Chao Yu <yuchao0@huawei.com>
Message-ID: <2503831f-3868-4037-307d-1e5fb4833a29@huawei.com>
Date: Mon, 4 Sep 2017 09:17:56 +0800
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On 2017/9/1 20:14, Yunlong Song wrote:
> se->ckpt_valid_blocks is always larger than se->valid_blocks, so
> get_ssr_cost can be cleared.

I think this is not correct.

Thanks,

> 
> Signed-off-by: Yunlong Song <yunlong.song@huawei.com>
> ---
>  fs/f2fs/gc.c | 11 +----------
>  1 file changed, 1 insertion(+), 10 deletions(-)
> 
> diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
> index cd147e7..b226760 100644
> --- a/fs/f2fs/gc.c
> +++ b/fs/f2fs/gc.c
> @@ -277,20 +277,11 @@ static unsigned int get_greedy_cost(struct f2fs_sb_info *sbi,
>  				valid_blocks * 2 : valid_blocks;
>  }
>  
> -static unsigned int get_ssr_cost(struct f2fs_sb_info *sbi,
> -						unsigned int segno)
> -{
> -	struct seg_entry *se = get_seg_entry(sbi, segno);
> -
> -	return se->ckpt_valid_blocks > se->valid_blocks ?
> -				se->ckpt_valid_blocks : se->valid_blocks;
> -}
> -
>  static inline unsigned int get_gc_cost(struct f2fs_sb_info *sbi,
>  			unsigned int segno, struct victim_sel_policy *p)
>  {
>  	if (p->alloc_mode == SSR)
> -		return get_ssr_cost(sbi, segno);
> +		return get_seg_entry(sbi, segno)->ckpt_valid_blocks;
>  
>  	/* alloc_mode == LFS */
>  	if (p->gc_mode == GC_GREEDY)
>