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From:   Miaohe Lin <linmiaohe@huawei.com>
To:     <akpm@linux-foundation.org>
CC:     <ying.huang@intel.com>, <songmuchun@bytedance.com>,
        <hch@infradead.org>, <willy@infradead.org>, <linux-mm@kvack.org>,
        <linux-kernel@vger.kernel.org>, <linmiaohe@huawei.com>
Subject: [PATCH v2 4/9] mm/vmscan: save a bit of stack space in shrink_lruvec
Date:   Sat, 9 Apr 2022 17:34:55 +0800
Message-ID: <20220409093500.10329-5-linmiaohe@huawei.com>
In-Reply-To: <20220409093500.10329-1-linmiaohe@huawei.com>
References: <20220409093500.10329-1-linmiaohe@huawei.com>
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LRU_UNEVICTABLE is not taken into account when shrink lruvec. So we can
save a bit of stack space by shrinking the array size of nr and targets
to NR_LRU_LISTS - 1. No functional change intended.

Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
---
 mm/vmscan.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/mm/vmscan.c b/mm/vmscan.c
index 59b96320f481..0e5818970998 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -2881,8 +2881,9 @@ static bool can_age_anon_pages(struct pglist_data *pgdat,
 
 static void shrink_lruvec(struct lruvec *lruvec, struct scan_control *sc)
 {
-	unsigned long nr[NR_LRU_LISTS];
-	unsigned long targets[NR_LRU_LISTS];
+	/* LRU_UNEVICTABLE is not taken into account. */
+	unsigned long nr[NR_LRU_LISTS - 1];
+	unsigned long targets[NR_LRU_LISTS - 1];
 	unsigned long nr_to_scan;
 	enum lru_list lru;
 	unsigned long nr_reclaimed = 0;
-- 
2.23.0