Eric Lee / linux-smarc-t335x-v3.2

11 Dec, 2008

1 commit

02 Dec, 2008

1 commit

  • dc19f9db3   memcg: memory hotplug fix for notifier callback ... Browse Code »

    Fixes for memcg/memory hotplug.

    While memory hotplug allocate/free memmap, page_cgroup doesn't free
    page_cgroup at OFFLINE when page_cgroup is allocated via bootomem.
    (Because freeing bootmem requires special care.)

    Then, if page_cgroup is allocated by bootmem and memmap is freed/allocated
    by memory hotplug, page_cgroup->page == page is no longer true.

    But current MEM_ONLINE handler doesn't check it and update
    page_cgroup->page if it's not necessary to allocate page_cgroup. (This
    was not found because memmap is not freed if SPARSEMEM_VMEMMAP is y.)

    And I noticed that MEM_ONLINE can be called against "part of section".
    So, freeing page_cgroup at CANCEL_ONLINE will cause trouble. (freeing
    used page_cgroup) Don't rollback at CANCEL.

    One more, current memory hotplug notifier is stopped by slub because it
    sets NOTIFY_STOP_MASK to return vaule. So, page_cgroup's callback never
    be called. (low priority than slub now.)

    I think this slub's behavior is not intentional(BUG). and fixes it.

    Another way to be considered about page_cgroup allocation:
    - free page_cgroup at OFFLINE even if it's from bootmem
    and remove specieal handler. But it requires more changes.

    Addresses http://bugzilla.kernel.org/show_bug.cgi?id=12041

    Signed-off-by: KAMEZAWA Hiruyoki
    Cc: Li Zefan
    Cc: Balbir Singh
    Cc: Pavel Emelyanov
    Tested-by: Badari Pulavarty
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    KAMEZAWA Hiroyuki
     

01 Dec, 2008

1 commit

13 Nov, 2008

1 commit

23 Oct, 2008

2 commits

  • 94b6da5ab   memcg: fix page_cgroup allocation ... Browse Code »

    page_cgroup_init() is called from mem_cgroup_init(). But at this
    point, we cannot call alloc_bootmem().
    (and this caused panic at boot.)

    This patch moves page_cgroup_init() to init/main.c.

    Time table is following:
    ==
    parse_args(). # we can trust mem_cgroup_subsys.disabled bit after this.
    ....
    cgroup_init_early() # "early" init of cgroup.
    ....
    setup_arch() # memmap is allocated.
    ...
    page_cgroup_init();
    mem_init(); # we cannot call alloc_bootmem after this.
    ....
    cgroup_init() # mem_cgroup is initialized.
    ==

    Before page_cgroup_init(), mem_map must be initialized. So,
    I added page_cgroup_init() to init/main.c directly.

    (*) maybe this is not very clean but
    - cgroup_init_early() is too early
    - in cgroup_init(), we have to use vmalloc instead of alloc_bootmem().
    use of vmalloc area in x86-32 is important and we should avoid very large
    vmalloc() in x86-32. So, we want to use alloc_bootmem() and added page_cgroup_init()
    directly to init/main.c

    [akpm@linux-foundation.org: remove unneeded/bad mem_cgroup_subsys declaration]
    [akpm@linux-foundation.org: fix build]
    Acked-by: Balbir Singh
    Tested-by: Balbir Singh
    Signed-off-by: KAMEZAWA Hiroyuki
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    KAMEZAWA Hiroyuki
     
  • 4c8210427   mm: page_cgroup needs linux/vmalloc.h for vmalloc_node()/vfree(). ... Browse Code »

    mm/page_cgroup.c: In function 'init_section_page_cgroup':
    mm/page_cgroup.c:111: error: implicit declaration of function 'vmalloc_node'
    mm/page_cgroup.c:111: warning: assignment makes pointer from integer without a cast
    mm/page_cgroup.c: In function '__free_page_cgroup':
    mm/page_cgroup.c:140: error: implicit declaration of function 'vfree'

    Signed-off-by: Paul Mundt
    Reviewed-by: KAMEZAWA Hiroyuki
    Cc: Heiko Carstens
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Paul Mundt
     

20 Oct, 2008

1 commit

  • 52d4b9ac0   memcg: allocate all page_cgroup at boot ... Browse Code »

    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
    Reviewed-by: Balbir Singh
    Cc: Daisuke Nishimura
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    KAMEZAWA Hiroyuki