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From:   Yejune Deng <yejune.deng@gmail.com>
To:     cl@linux.com, penberg@kernel.org, rientjes@google.com,
        iamjoonsoo.kim@lge.com, akpm@linux-foundation.org, vbabka@suse.cz
Cc:     linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        Yejune Deng <yejunedeng@gmail.com>
Subject: [PATCH 2/2] mm: slub: use DEFINE_RAW_SPINLOCK init object_map_lock
Date:   Tue, 25 May 2021 18:23:55 +0800
Message-Id: <1621938235-11947-2-git-send-email-yejunedeng@gmail.com>
In-Reply-To: <1621938235-11947-1-git-send-email-yejunedeng@gmail.com>
References: <1621938235-11947-1-git-send-email-yejunedeng@gmail.com>
Precedence: bulk

Use DEFINE_RAW_SPINLOCK instead of DEFINE_SPINLOCK object_map_lock
that won't be preempted on mainline and PREEMPT_RT kernels.

Signed-off-by: Yejune Deng <yejunedeng@gmail.com>
---
 mm/slub.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/mm/slub.c b/mm/slub.c
index c2f63c3..995f3d0 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -445,7 +445,7 @@ static inline bool cmpxchg_double_slab(struct kmem_cache *s, struct page *page,
 
 #ifdef CONFIG_SLUB_DEBUG
 static unsigned long object_map[BITS_TO_LONGS(MAX_OBJS_PER_PAGE)];
-static DEFINE_SPINLOCK(object_map_lock);
+static DEFINE_RAW_SPINLOCK(object_map_lock);
 
 #if IS_ENABLED(CONFIG_KUNIT)
 static bool slab_add_kunit_errors(void)
@@ -481,7 +481,7 @@ static unsigned long *get_map(struct kmem_cache *s, struct page *page)
 
 	VM_BUG_ON(!irqs_disabled());
 
-	spin_lock(&object_map_lock);
+	raw_spin_lock(&object_map_lock);
 
 	bitmap_zero(object_map, page->objects);
 
@@ -494,7 +494,7 @@ static unsigned long *get_map(struct kmem_cache *s, struct page *page)
 static void put_map(unsigned long *map) __releases(&object_map_lock)
 {
 	VM_BUG_ON(map != object_map);
-	spin_unlock(&object_map_lock);
+	raw_spin_unlock(&object_map_lock);
 }
 
 static inline unsigned int size_from_object(struct kmem_cache *s)
-- 
2.7.4