From 9f835703ea67633617ca82bc150f6ee70831b40a Mon Sep 17 00:00:00 2001
From: Wei Yang <weiyang@linux.vnet.ibm.com>
Date: Thu, 5 Nov 2015 18:45:51 -0800
Subject: [PATCH] mm/slub: calculate start order with reserved in consideration
In slub_order(), the order starts from max(min_order,
get_order(min_objects * size)). When (min_objects * size) has different
order from (min_objects * size + reserved), it will skip this order via a
check in the loop.
This patch optimizes this a little by calculating the start order with
`reserved' in consideration and removing the check in loop.
Signed-off-by: Wei Yang <weiyang@linux.vnet.ibm.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
mm/slub.c | 6 +-----
1 file changed, 1 insertion(+), 5 deletions(-)
diff --git a/mm/slub.c b/mm/slub.c
index e309ed140fd18c..e1bb147827ef23 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -2912,19 +2912,15 @@ static inline int slab_order(int size, int min_objects,
if (order_objects(min_order, size, reserved) > MAX_OBJS_PER_PAGE)
return get_order(size * MAX_OBJS_PER_PAGE) - 1;
- for (order = max(min_order, get_order(min_objects * size));
+ for (order = max(min_order, get_order(min_objects * size + reserved));
order <= max_order; order++) {
unsigned long slab_size = PAGE_SIZE << order;
- if (slab_size < min_objects * size + reserved)
- continue;
-
rem = (slab_size - reserved) % size;
if (rem <= slab_size / fract_leftover)
break;
-
}
return order;
--
GitLab