]> git.proxmox.com Git - mirror_ubuntu-disco-kernel.git/commit
memcg: allocate all page_cgroup at boot
authorKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Sun, 19 Oct 2008 03:28:16 +0000 (20:28 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Mon, 20 Oct 2008 15:52:39 +0000 (08:52 -0700)
commit52d4b9ac0b985168009c2a57098324e67bae171f
treeb3e3b854166930af893be90ea30a7ab0d65c59e7
parentc05555b572921c464d064d9267f7f7bc06d424fa
memcg: allocate all page_cgroup at boot

Allocate all page_cgroup at boot and remove page_cgroup poitner from
struct page.  This patch adds an interface as

 struct page_cgroup *lookup_page_cgroup(struct page*)

All FLATMEM/DISCONTIGMEM/SPARSEMEM  and MEMORY_HOTPLUG is supported.

Remove page_cgroup pointer reduces the amount of memory by
 - 4 bytes per PAGE_SIZE.
 - 8 bytes per PAGE_SIZE
if memory controller is disabled. (even if configured.)

On usual 8GB x86-32 server, this saves 8MB of NORMAL_ZONE memory.
On my x86-64 server with 48GB of memory, this saves 96MB of memory.
I think this reduction makes sense.

By pre-allocation, kmalloc/kfree in charge/uncharge are removed.
This means
  - we're not necessary to be afraid of kmalloc faiulre.
    (this can happen because of gfp_mask type.)
  - we can avoid calling kmalloc/kfree.
  - we can avoid allocating tons of small objects which can be fragmented.
  - we can know what amount of memory will be used for this extra-lru handling.

I added printk message as

"allocated %ld bytes of page_cgroup"
        "please try cgroup_disable=memory option if you don't want"

maybe enough informative for users.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Reviewed-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
include/linux/memcontrol.h
include/linux/mm_types.h
include/linux/mmzone.h
include/linux/page_cgroup.h [new file with mode: 0644]
mm/Makefile
mm/memcontrol.c
mm/page_alloc.c
mm/page_cgroup.c [new file with mode: 0644]