linux-kernel - [PATCH] mm: swap: Use memset to fill the swap_map with SWAP_HAS

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Message-ID: <20200921122224.7139-1-linmiaohe@huawei.com>
Date:   Mon, 21 Sep 2020 08:22:24 -0400
From:   Miaohe Lin <linmiaohe@...wei.com>
To:     <akpm@...ux-foundation.org>
CC:     <linux-mm@...ck.org>, <linux-kernel@...r.kernel.org>,
        <linmiaohe@...wei.com>
Subject: [PATCH] mm: swap: Use memset to fill the swap_map with SWAP_HAS_CACHE

We could use helper memset to fill the swap_map with SWAP_HAS_CACHE instead
of a direct loop here to simplify the code. Also we can remove the local
variable i and map this way.

Signed-off-by: Miaohe Lin <linmiaohe@...wei.com>
---
 mm/swapfile.c | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/mm/swapfile.c b/mm/swapfile.c
index 8feaab31a3a9..b0b629b24e3a 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -975,8 +975,7 @@ static int swap_alloc_cluster(struct swap_info_struct *si, swp_entry_t *slot)
 {
 	unsigned long idx;
 	struct swap_cluster_info *ci;
-	unsigned long offset, i;
-	unsigned char *map;
+	unsigned long offset;
 
 	/*
 	 * Should not even be attempting cluster allocations when huge
@@ -996,9 +995,7 @@ static int swap_alloc_cluster(struct swap_info_struct *si, swp_entry_t *slot)
 	alloc_cluster(si, idx);
 	cluster_set_count_flag(ci, SWAPFILE_CLUSTER, CLUSTER_FLAG_HUGE);
 
-	map = si->swap_map + offset;
-	for (i = 0; i < SWAPFILE_CLUSTER; i++)
-		map[i] = SWAP_HAS_CACHE;
+	memset(si->swap_map + offset, SWAP_HAS_CACHE, SWAPFILE_CLUSTER);
 	unlock_cluster(ci);
 	swap_range_alloc(si, offset, SWAPFILE_CLUSTER);
 	*slot = swp_entry(si->type, offset);
-- 
2.19.1