linux-kernel - [PATCH v3 4/5] mm/memory-failure: move hwpoison

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Message-Id: <20240521235429.2368017-5-jane.chu@oracle.com>
Date: Tue, 21 May 2024 17:54:28 -0600
From: Jane Chu <jane.chu@...cle.com>
To: linmiaohe@...wei.com, nao.horiguchi@...il.com, akpm@...ux-foundation.org,
        osalvador@...e.de, linux-mm@...ck.org, linux-kernel@...r.kernel.org
Subject: [PATCH v3 4/5] mm/memory-failure: move hwpoison_filter() higher up

Move hwpoison_filter() higher up as there is no need to spend a lot
cycles only to find out later that the page is supposed to be skipped
from hwpoison handling.

Signed-off-by: Jane Chu <jane.chu@...cle.com>
---
 mm/memory-failure.c | 20 ++++++++++++--------
 1 file changed, 12 insertions(+), 8 deletions(-)

diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index 1e22d73c9329..794196951a04 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -2301,6 +2301,18 @@ int memory_failure(unsigned long pfn, int flags)
 	}
 
 	folio = page_folio(p);
+
+	/* filter pages that are protected from hwpoison test by users */
+	folio_lock(folio);
+	if (hwpoison_filter(p)) {
+		ClearPageHWPoison(p);
+		folio_unlock(folio);
+		folio_put(folio);
+		res = -EOPNOTSUPP;
+		goto unlock_mutex;
+	}
+	folio_unlock(folio);
+
 	if (folio_test_large(folio)) {
 		/*
 		 * The flag must be set after the refcount is bumped
@@ -2364,14 +2376,6 @@ int memory_failure(unsigned long pfn, int flags)
 	 */
 	page_flags = folio->flags;
 
-	if (hwpoison_filter(p)) {
-		ClearPageHWPoison(p);
-		folio_unlock(folio);
-		folio_put(folio);
-		res = -EOPNOTSUPP;
-		goto unlock_mutex;
-	}
-
 	/*
 	 * __munlock_folio() may clear a writeback folio's LRU flag without
 	 * the folio lock. We need to wait for writeback completion for this
-- 
2.39.3