From: Zhongkun He <hezhongkun.hzk@bytedance.com>
Date: Mon, 21 Apr 2025 09:13:29 +0000 (+0800)
Subject: mm: vmscan: add more comments about cache_trim_mode
X-Git-Tag: v6.16-rc1~92^2~120
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=aded729f64d3eb1543abc7e6a3a20069716efb7d;p=thirdparty%2Fkernel%2Flinux.git

mm: vmscan: add more comments about cache_trim_mode

Add more comments for cache_trim_mode, and the annotations provided by
Johannes Weiner in [1].

Link: https://lore.kernel.org/all/20250314141833.GA1316033@cmpxchg.org/
Link: https://lkml.kernel.org/r/4baad87ba637f1e6f666e9b99b3fdcb7ab39171b.1745225696.git.hezhongkun.hzk@bytedance.com
Signed-off-by: Zhongkun He <hezhongkun.hzk@bytedance.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Yosry Ahmed <yosry.ahmed@linux.dev>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

diff --git a/mm/vmscan.c b/mm/vmscan.c
index 495889f621b55..ca786575b6c2e 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -2536,7 +2536,8 @@ static void get_scan_count(struct lruvec *lruvec, struct scan_control *sc,
 
 	/*
 	 * If there is enough inactive page cache, we do not reclaim
-	 * anything from the anonymous working right now.
+	 * anything from the anonymous working right now to make sure
+         * a streaming file access pattern doesn't cause swapping.
 	 */
 	if (sc->cache_trim_mode) {
 		scan_balance = SCAN_FILE;