From: Kemeng Shi <shikemeng@huaweicloud.com>
Date: Tue, 25 Mar 2025 16:25:24 +0000 (+0800)
Subject: mm: swap: use swap_entries_free() drop last ref count in swap_entries_put_nr()
X-Git-Tag: v6.16-rc1~92^2~237
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=46e0ab2c62067a8d5e62ae90088b1743af83725d;p=thirdparty%2Fkernel%2Flinux.git

mm: swap: use swap_entries_free() drop last ref count in swap_entries_put_nr()

Use swap_entries_free() to directly free swap entries when the swap
entries are not cached and referenced, without needing to set swap entries
to set intermediate SWAP_HAS_CACHE state.

Link: https://lkml.kernel.org/r/20250325162528.68385-5-shikemeng@huaweicloud.com
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Reviewed-by: Tim Chen <tim.c.chen@linux.intel.com>
Reviewed-by: Baoquan He <bhe@redhat.com>
Cc: Kairui Song <kasong@tencent.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

diff --git a/mm/swapfile.c b/mm/swapfile.c
index f0ba27db9b3ed..f8fe507be4f35 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -1498,10 +1498,11 @@ static bool swap_entries_put_nr(struct swap_info_struct *si,
 		unlock_cluster(ci);
 		goto fallback;
 	}
-	for (i = 0; i < nr; i++)
-		WRITE_ONCE(si->swap_map[offset + i], SWAP_HAS_CACHE);
 	if (!has_cache)
 		swap_entries_free(si, ci, entry, nr);
+	else
+		for (i = 0; i < nr; i++)
+			WRITE_ONCE(si->swap_map[offset + i], SWAP_HAS_CACHE);
 	unlock_cluster(ci);
 
 	return has_cache;