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From:   Zhiguo Jiang <justinjiang@vivo.com>
To:     Andrew Morton <akpm@linux-foundation.org>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Cc:     opensource.kernel@vivo.com, Zhiguo Jiang <justinjiang@vivo.com>
Subject: [PATCH] mm:vmscan: fix return negative unneed to detect VM_EXEC
Date:   Wed, 25 Oct 2023 23:44:32 +0800
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The reason that folio_referenced() returns negative is because
rwc.contended is 1, vm_flags is 0 at this time and so there is
no need to detect VM_EXEC. And only when referenced > 0, pra->vm_flags
will be filled with vma->vm_flags in folio_referenced_one().

Signed-off-by: Zhiguo Jiang <justinjiang@vivo.com>
---
 mm/vmscan.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/vmscan.c b/mm/vmscan.c
index e587dafeef94..f0b4325cccd4 100755
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -2095,7 +2095,7 @@ static void shrink_active_list(unsigned long nr_to_scan,
 
 		/* Referenced or rmap lock contention: rotate */
 		if (folio_referenced(folio, 0, sc->target_mem_cgroup,
-				     &vm_flags) != 0) {
+				     &vm_flags) > 0) {
 			/*
 			 * Identify referenced, file-backed active folios and
 			 * give them one more trip around the active list. So
--
2.39.0