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Date:   Mon, 12 Jul 2021 09:24:25 +0200
From:   Michal Hocko <mhocko@suse.com>
To:     Miaohe Lin <linmiaohe@huawei.com>
Cc:     akpm@linux-foundation.org, hannes@cmpxchg.org, vbabka@suse.cz,
        axboe@kernel.dk, iamjoonsoo.kim@lge.com, alexs@kernel.org,
        apopple@nvidia.com, willy@infradead.org, minchan@kernel.org,
        david@redhat.com, shli@fb.com, hillf.zj@alibaba-inc.com,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/5] mm/vmscan: remove misleading setting to sc->priority
Message-ID: <YOvuKZ4kZ/1BJ5VC@dhcp22.suse.cz>
References: <20210710100329.49174-1-linmiaohe@huawei.com>
 <20210710100329.49174-3-linmiaohe@huawei.com>
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On Sat 10-07-21 18:03:26, Miaohe Lin wrote:
> The priority field of sc is used to control how many pages we should scan
> at once while we always traverse the list to shrink the pages in these
> functions. So these settings are unneeded and misleading.

I dunno. I agree that priority is not really used as these operate on
page lists but I am not sure this is worth touching.

> Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
> ---
>  mm/vmscan.c | 2 --
>  1 file changed, 2 deletions(-)
> 
> diff --git a/mm/vmscan.c b/mm/vmscan.c
> index 6483fe0e2065..fbe53e60b248 100644
> --- a/mm/vmscan.c
> +++ b/mm/vmscan.c
> @@ -1702,7 +1702,6 @@ unsigned int reclaim_clean_pages_from_list(struct zone *zone,
>  {
>  	struct scan_control sc = {
>  		.gfp_mask = GFP_KERNEL,
> -		.priority = DEF_PRIORITY,
>  		.may_unmap = 1,
>  	};
>  	struct reclaim_stat stat;
> @@ -2327,7 +2326,6 @@ unsigned long reclaim_pages(struct list_head *page_list)
>  	unsigned int noreclaim_flag;
>  	struct scan_control sc = {
>  		.gfp_mask = GFP_KERNEL,
> -		.priority = DEF_PRIORITY,
>  		.may_writepage = 1,
>  		.may_unmap = 1,
>  		.may_swap = 1,
> -- 
> 2.23.0

-- 
Michal Hocko
SUSE Labs