From 832a15d209cd260180407bde1af18965b21623f3 Mon Sep 17 00:00:00 2001
From: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Date: Tue, 15 Mar 2016 14:54:33 -0700
Subject: [PATCH] mm/slab: align cache size first before determination of
OFF_SLAB candidate
Finding suitable OFF_SLAB candidate is more related to aligned cache
size rather than original size. Same reasoning can be applied to the
debug pagealloc candidate. So, this patch moves up alignment fixup to
proper position. From that point, size is aligned so we can remove some
alignment fixups.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
mm/slab.c | 26 +++++++++++++++-----------
1 file changed, 15 insertions(+), 11 deletions(-)
diff --git a/mm/slab.c b/mm/slab.c
index b3d91b048f44..d5dffc806f82 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -2125,6 +2125,17 @@ __kmem_cache_create (struct kmem_cache *cachep, unsigned long flags)
else
size += BYTES_PER_WORD;
}
+#endif
+
+ size = ALIGN(size, cachep->align);
+ /*
+ * We should restrict the number of objects in a slab to implement
+ * byte sized index. Refer comment on SLAB_OBJ_MIN_SIZE definition.
+ */
+ if (FREELIST_BYTE_INDEX && size < SLAB_OBJ_MIN_SIZE)
+ size = ALIGN(SLAB_OBJ_MIN_SIZE, cachep->align);
+
+#if DEBUG
/*
* To activate debug pagealloc, off-slab management is necessary
* requirement. In early phase of initialization, small sized slab
@@ -2135,8 +2146,8 @@ __kmem_cache_create (struct kmem_cache *cachep, unsigned long flags)
if (debug_pagealloc_enabled() && (flags & SLAB_POISON) &&
!slab_early_init && size >= kmalloc_size(INDEX_NODE) &&
size >= 256 && cachep->object_size > cache_line_size() &&
- ALIGN(size, cachep->align) < PAGE_SIZE) {
- cachep->obj_offset += PAGE_SIZE - ALIGN(size, cachep->align);
+ size < PAGE_SIZE) {
+ cachep->obj_offset += PAGE_SIZE - size;
size = PAGE_SIZE;
}
#endif
@@ -2148,20 +2159,13 @@ __kmem_cache_create (struct kmem_cache *cachep, unsigned long flags)
* SLAB_NOLEAKTRACE to avoid recursive calls into kmemleak)
*/
if (size >= OFF_SLAB_MIN_SIZE && !slab_early_init &&
- !(flags & SLAB_NOLEAKTRACE))
+ !(flags & SLAB_NOLEAKTRACE)) {
/*
* Size is large, assume best to place the slab management obj
* off-slab (should allow better packing of objs).
*/
flags |= CFLGS_OFF_SLAB;
-
- size = ALIGN(size, cachep->align);
- /*
- * We should restrict the number of objects in a slab to implement
- * byte sized index. Refer comment on SLAB_OBJ_MIN_SIZE definition.
- */
- if (FREELIST_BYTE_INDEX && size < SLAB_OBJ_MIN_SIZE)
- size = ALIGN(SLAB_OBJ_MIN_SIZE, cachep->align);
+ }
left_over = calculate_slab_order(cachep, size, flags);
--
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