From a9189d5b88dd1acfb543a9b940b49294ea226297 Mon Sep 17 00:00:00 2001
From: Wang ShaoBo <bobo.shaobowang@huawei.com>
Date: Fri, 5 Nov 2021 13:40:55 -0700
Subject: [PATCH] mm/page_alloc: use clamp() to simplify code

References: bsc#1190208 (MM functional and performance backports)
Patch-mainline: v5.16-rc1
Git-commit: 59d336bdf6931a6a8c2ba41e533267d1cc799fc9

This patch uses clamp() to simplify code in init_per_zone_wmark_min().

Link: https://lkml.kernel.org/r/20211021034830.1049150-1-bobo.shaobowang@huawei.com
Signed-off-by: Wang ShaoBo <bobo.shaobowang@huawei.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Wei Yongjun <weiyongjun1@huawei.com>
Cc: Li Bin <huawei.libin@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Mel Gorman <mgorman@suse.de>
---
 mm/page_alloc.c | 12 ++++--------
 1 file changed, 4 insertions(+), 8 deletions(-)

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index def88c43c482..e611706a3a96 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -8480,16 +8480,12 @@ int __meminit init_per_zone_wmark_min(void)
 	lowmem_kbytes = nr_free_buffer_pages() * (PAGE_SIZE >> 10);
 	new_min_free_kbytes = int_sqrt(lowmem_kbytes * 16);
 
-	if (new_min_free_kbytes > user_min_free_kbytes) {
-		min_free_kbytes = new_min_free_kbytes;
-		if (min_free_kbytes < 128)
-			min_free_kbytes = 128;
-		if (min_free_kbytes > 262144)
-			min_free_kbytes = 262144;
-	} else {
+	if (new_min_free_kbytes > user_min_free_kbytes)
+		min_free_kbytes = clamp(new_min_free_kbytes, 128, 262144);
+	else
 		pr_warn("min_free_kbytes is not updated to %d because user defined value %d is preferred\n",
 				new_min_free_kbytes, user_min_free_kbytes);
-	}
+
 	setup_per_zone_wmarks();
 	refresh_zone_stat_thresholds();
 	setup_per_zone_lowmem_reserve();