redonkable/alistair23-linux
redonkable/alistair23-linux
1
0
Fork 0
Code Releases Activity

mm/slub.c: pack red_left_pad with another int to save a word

Browse source 
Patch series "try to save some memory for kmem_cache in some cases", v2.

kmem_cache is a frequently used data in kernel.  During the code
reading, I found maybe we could save some space in some cases.

1. On 64bit arch, type int will occupy a word if it doesn't sit well.

2. cpu_slab->partial is just used when CONFIG_SLUB_CPU_PARTIAL is set

3. cpu_partial is just used when CONFIG_SLUB_CPU_PARTIAL is set, while
   just save some space on 32bit arch.

This patch (of 3):

On 64bit arch, struct is 8-bytes aligned, so int will occupy a word if
it doesn't sit well.

This patch pack red_left_pad with reserved to save 8 bytes for struct
kmem_cache on a 64bit arch.

Link: http://lkml.kernel.org/r/20170502144533.10729-2-richard.weiyang@gmail.com
Signed-off-by: Wei Yang <richard.weiyang@gmail.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>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Wei Yang 2017-07-06 15:36:28 -07:00 committed by Linus Torvalds
parent d4ff6d35f6
commit d3111e6cce
1 changed files with 1 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

2
include/linux/slub_def.h
View file

@ -79,9 +79,9 @@ struct kmem_cache {
int inuse; /* Offset to metadata */
int align; /* Alignment */
int reserved; /* Reserved bytes at the end of slabs */
int red_left_pad; /* Left redzone padding size */
const char *name; /* Name (only for display!) */
struct list_head list; /* List of slab caches */
int red_left_pad; /* Left redzone padding size */
#ifdef CONFIG_SYSFS
struct kobject kobj; /* For sysfs */
struct work_struct kobj_remove_work;