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From:   Pengfei Li <lpf.vector@gmail.com>
To:     akpm@linux-foundation.org
Cc:     vbabka@suse.cz, cl@linux.com, penberg@kernel.org,
        rientjes@google.com, iamjoonsoo.kim@lge.com, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, guro@fb.com,
        Pengfei Li <lpf.vector@gmail.com>
Subject: [PATCH v3 4/4] mm, slab_common: Make the loop for initializing KMALLOC_DMA start from 1
Date:   Tue, 10 Sep 2019 09:26:52 +0800
Message-Id: <20190910012652.3723-5-lpf.vector@gmail.com>
In-Reply-To: <20190910012652.3723-1-lpf.vector@gmail.com>
References: <20190910012652.3723-1-lpf.vector@gmail.com>
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KMALLOC_DMA will be initialized only if KMALLOC_NORMAL with
the same index exists.

And kmalloc_caches[KMALLOC_NORMAL][0] is always NULL.

Therefore, the loop that initializes KMALLOC_DMA should start
at 1 instead of 0, which will reduce 1 meaningless attempt.

Signed-off-by: Pengfei Li <lpf.vector@gmail.com>
---
 mm/slab_common.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/slab_common.c b/mm/slab_common.c
index af45b5278fdc..c81fc7dc2946 100644
--- a/mm/slab_common.c
+++ b/mm/slab_common.c
@@ -1236,7 +1236,7 @@ void __init create_kmalloc_caches(slab_flags_t flags)
 	slab_state = UP;
 
 #ifdef CONFIG_ZONE_DMA
-	for (i = 0; i <= KMALLOC_SHIFT_HIGH; i++) {
+	for (i = 1; i <= KMALLOC_SHIFT_HIGH; i++) {
 		struct kmem_cache *s = kmalloc_caches[KMALLOC_NORMAL][i];
 
 		if (s) {
-- 
2.21.0