[PATCH 1/4] mm/slub: simplify the last resort slab order calculation

From: Vlastimil Babka <vbabka@suse.cz>
To: David Rientjes <rientjes@google.com>,
	Christoph Lameter <cl@linux.com>,
	Hyeonggon Yoo <42.hyeyoo@gmail.com>,
	Jay Patel <jaypatel@linux.ibm.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>,
	Pekka Enberg <penberg@kernel.org>,
	Joonsoo Kim <iamjoonsoo.kim@lge.com>,
	linux-mm@kvack.org, patches@lists.linux.dev,
	linux-kernel@vger.kernel.org, Vlastimil Babka <vbabka@suse.cz>
Subject: [PATCH 1/4] mm/slub: simplify the last resort slab order calculation
Date: Fri,  8 Sep 2023 16:53:04 +0200	[thread overview]
Message-ID: <20230908145302.30320-7-vbabka@suse.cz> (raw)
In-Reply-To: <20230908145302.30320-6-vbabka@suse.cz>

If calculate_order() can't fit even a single large object within
slub_max_order, it will try using the smallest necessary order that may
exceed slub_max_order but not MAX_ORDER.

Currently this is done with a call to calc_slab_order() which is
unecessary. We can simply use get_order(size). No functional change.

Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
---
 mm/slub.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/slub.c b/mm/slub.c
index f7940048138c..c6e694cb17b9 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -4193,7 +4193,7 @@ static inline int calculate_order(unsigned int size)
 	/*
 	 * Doh this slab cannot be placed using slub_max_order.
 	 */
-	order = calc_slab_order(size, 1, MAX_ORDER, 1);
+	order = get_order(size);
 	if (order <= MAX_ORDER)
 		return order;
 	return -ENOSYS;
-- 
2.42.0

