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Message-ID: <062e3adc-6d01-aa9a-8480-a4d845d4d4fe@linux.alibaba.com>
Date:   Wed, 2 Aug 2023 10:32:45 +0800
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Subject: Re: [PATCH 2/5] mm/compaction: set compact_cached_free_pfn correctly
 in update_pageblock_skip
To:     Kemeng Shi <shikemeng@huaweicloud.com>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, akpm@linux-foundation.org
Cc:     mgorman@techsingularity.net, willy@infradead.org, david@redhat.com
References: <20230729174354.2239980-1-shikemeng@huaweicloud.com>
 <20230729174354.2239980-3-shikemeng@huaweicloud.com>
From:   Baolin Wang <baolin.wang@linux.alibaba.com>
In-Reply-To: <20230729174354.2239980-3-shikemeng@huaweicloud.com>
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On 7/30/2023 1:43 AM, Kemeng Shi wrote:
> We will set skip to page block of block_start_pfn, it's more reasonable
> to set compact_cached_free_pfn to page block before the block_start_pfn.

Looks reasonable to me.
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>

> Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
> ---
>   mm/compaction.c | 3 ++-
>   1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/mm/compaction.c b/mm/compaction.c
> index d1d28d57e5bd..4a784872565a 100644
> --- a/mm/compaction.c
> +++ b/mm/compaction.c
> @@ -1690,7 +1690,8 @@ static void isolate_freepages(struct compact_control *cc)
>   
>   		/* Update the skip hint if the full pageblock was scanned */
>   		if (isolate_start_pfn >= block_end_pfn)
> -			update_pageblock_skip(cc, page, block_start_pfn);
> +			update_pageblock_skip(cc, page, block_start_pfn -
> +					      pageblock_nr_pages);
>   
>   		/* Are enough freepages isolated? */
>   		if (cc->nr_freepages >= cc->nr_migratepages) {