14 Jan, 2011

2 commits

  • PG_buddy can be converted to _mapcount == -2. So the PG_compound_lock can
    be added to page->flags without overflowing (because of the sparse section
    bits increasing) with CONFIG_X86_PAE=y and CONFIG_X86_PAT=y. This also
    has to move the memory hotplug code from _mapcount to lru.next to avoid
    any risk of clashes. We can't use lru.next for PG_buddy removal, but
    memory hotplug can use lru.next even more easily than the mapcount
    instead.

    Signed-off-by: Andrea Arcangeli
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Andrea Arcangeli
     
  • Add a PageSlab() check before adding the _mapcount value to /kpagecount.
    page->_mapcount is in a union with the SLAB structure so for pages
    controlled by SLAB, page_mapcount() returns nonsense.

    Signed-off-by: Petr Holasek
    Cc: Wu Fengguang
    Cc: Matt Mackall
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Petr Holasek
     

10 Sep, 2010

1 commit


16 Dec, 2009

1 commit

  • Rename get_uflags() to stable_page_flags() and make it a global function
    for use in the hwpoison page flags filter, which need to compare user
    page flags with the value provided by user space.

    Also move KPF_* to kernel-page-flags.h for use by user space tools.

    Acked-by: Matt Mackall
    Signed-off-by: Andi Kleen
    CC: Nick Piggin
    CC: Christoph Lameter
    Signed-off-by: Wu Fengguang
    Signed-off-by: Andi Kleen

    Wu Fengguang
     

08 Oct, 2009

1 commit

  • This flag indicates a hardware detected memory corruption on the page.
    Any future access of the page data may bring down the machine.

    Signed-off-by: Wu Fengguang
    Cc: Andi Kleen
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Wu Fengguang
     

22 Sep, 2009

1 commit

  • KSM will need to identify its kernel merged pages unambiguously, and
    /proc/kpageflags will probably like to do so too.

    Since KSM will only be substituting anonymous pages, statistics are best
    preserved by making a PageKsm page a special PageAnon page: one with no
    anon_vma.

    But KSM then needs its own page_add_ksm_rmap() - keep it in ksm.h near
    PageKsm; and do_wp_page() must COW them, unlike singly mapped PageAnons.

    Signed-off-by: Hugh Dickins
    Signed-off-by: Chris Wright
    Signed-off-by: Izik Eidus
    Cc: Wu Fengguang
    Cc: Andrea Arcangeli
    Cc: Rik van Riel
    Cc: Wu Fengguang
    Cc: Balbir Singh
    Cc: Hugh Dickins
    Cc: KAMEZAWA Hiroyuki
    Cc: Lee Schermerhorn
    Cc: Avi Kivity
    Cc: Nick Piggin
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Hugh Dickins
     

17 Jun, 2009

4 commits

  • Currently, nobody wants to turn UNEVICTABLE_LRU off. Thus this
    configurability is unnecessary.

    Signed-off-by: KOSAKI Motohiro
    Cc: Johannes Weiner
    Cc: Andi Kleen
    Acked-by: Minchan Kim
    Cc: David Woodhouse
    Cc: Matt Mackall
    Cc: Rik van Riel
    Cc: Lee Schermerhorn
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    KOSAKI Motohiro
     
  • Export all page flags faithfully in /proc/kpageflags.

    11. KPF_MMAP (pseudo flag) memory mapped page
    12. KPF_ANON (pseudo flag) memory mapped page (anonymous)
    13. KPF_SWAPCACHE page is in swap cache
    14. KPF_SWAPBACKED page is swap/RAM backed
    15. KPF_COMPOUND_HEAD (*)
    16. KPF_COMPOUND_TAIL (*)
    17. KPF_HUGE hugeTLB pages
    18. KPF_UNEVICTABLE page is in the unevictable LRU list
    19. KPF_HWPOISON(TBD) hardware detected corruption
    20. KPF_NOPAGE (pseudo flag) no page frame at the address
    32-39. more obscure flags for kernel developers

    (*) For compound pages, exporting _both_ head/tail info enables
    users to tell where a compound page starts/ends, and its order.

    The accompanying page-types tool will handle the details like decoupling
    overloaded flags and hiding obscure flags to normal users.

    Thanks to KOSAKI and Andi for their valuable recommendations!

    Signed-off-by: Wu Fengguang
    Cc: KOSAKI Motohiro
    Cc: Andi Kleen
    Cc: Matt Mackall
    Cc: Alexey Dobriyan
    Cc: Ingo Molnar
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Wu Fengguang
     
  • Move increments of pfn/out to bottom of the loop.

    Signed-off-by: Wu Fengguang
    Cc: KOSAKI Motohiro
    Cc: Andi Kleen
    Acked-by: Matt Mackall
    Cc: Alexey Dobriyan
    Cc: Ingo Molnar
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Wu Fengguang
     
  • A series of patches to enhance the /proc/pagemap interface and to add a
    userspace executable which can be used to present the pagemap data.

    Export 10 more flags to end users (and more for kernel developers):

    11. KPF_MMAP (pseudo flag) memory mapped page
    12. KPF_ANON (pseudo flag) memory mapped page (anonymous)
    13. KPF_SWAPCACHE page is in swap cache
    14. KPF_SWAPBACKED page is swap/RAM backed
    15. KPF_COMPOUND_HEAD (*)
    16. KPF_COMPOUND_TAIL (*)
    17. KPF_HUGE hugeTLB pages
    18. KPF_UNEVICTABLE page is in the unevictable LRU list
    19. KPF_HWPOISON hardware detected corruption
    20. KPF_NOPAGE (pseudo flag) no page frame at the address

    (*) For compound pages, exporting _both_ head/tail info enables
    users to tell where a compound page starts/ends, and its order.

    a simple demo of the page-types tool

    # ./page-types -h
    page-types [options]
    -r|--raw Raw mode, for kernel developers
    -a|--addr addr-spec Walk a range of pages
    -b|--bits bits-spec Walk pages with specified bits
    -l|--list Show page details in ranges
    -L|--list-each Show page details one by one
    -N|--no-summary Don't show summay info
    -h|--help Show this usage message
    addr-spec:
    N one page at offset N (unit: pages)
    N+M pages range from N to N+M-1
    N,M pages range from N to M-1
    N, pages range from N to end
    ,M pages range from 0 to M
    bits-spec:
    bit1,bit2 (flags & (bit1|bit2)) != 0
    bit1,bit2=bit1 (flags & (bit1|bit2)) == bit1
    bit1,~bit2 (flags & (bit1|bit2)) == bit1
    =bit1,bit2 flags == (bit1|bit2)
    bit-names:
    locked error referenced uptodate
    dirty lru active slab
    writeback reclaim buddy mmap
    anonymous swapcache swapbacked compound_head
    compound_tail huge unevictable hwpoison
    nopage reserved(r) mlocked(r) mappedtodisk(r)
    private(r) private_2(r) owner_private(r) arch(r)
    uncached(r) readahead(o) slob_free(o) slub_frozen(o)
    slub_debug(o)
    (r) raw mode bits (o) overloaded bits

    # ./page-types
    flags page-count MB symbolic-flags long-symbolic-flags
    0x0000000000000000 487369 1903 _________________________________
    0x0000000000000014 5 0 __R_D____________________________ referenced,dirty
    0x0000000000000020 1 0 _____l___________________________ lru
    0x0000000000000024 34 0 __R__l___________________________ referenced,lru
    0x0000000000000028 3838 14 ___U_l___________________________ uptodate,lru
    0x0001000000000028 48 0 ___U_l_______________________I___ uptodate,lru,readahead
    0x000000000000002c 6478 25 __RU_l___________________________ referenced,uptodate,lru
    0x000100000000002c 47 0 __RU_l_______________________I___ referenced,uptodate,lru,readahead
    0x0000000000000040 8344 32 ______A__________________________ active
    0x0000000000000060 1 0 _____lA__________________________ lru,active
    0x0000000000000068 348 1 ___U_lA__________________________ uptodate,lru,active
    0x0001000000000068 12 0 ___U_lA______________________I___ uptodate,lru,active,readahead
    0x000000000000006c 988 3 __RU_lA__________________________ referenced,uptodate,lru,active
    0x000100000000006c 48 0 __RU_lA______________________I___ referenced,uptodate,lru,active,readahead
    0x0000000000004078 1 0 ___UDlA_______b__________________ uptodate,dirty,lru,active,swapbacked
    0x000000000000407c 34 0 __RUDlA_______b__________________ referenced,uptodate,dirty,lru,active,swapbacked
    0x0000000000000400 503 1 __________B______________________ buddy
    0x0000000000000804 1 0 __R________M_____________________ referenced,mmap
    0x0000000000000828 1029 4 ___U_l_____M_____________________ uptodate,lru,mmap
    0x0001000000000828 43 0 ___U_l_____M_________________I___ uptodate,lru,mmap,readahead
    0x000000000000082c 382 1 __RU_l_____M_____________________ referenced,uptodate,lru,mmap
    0x000100000000082c 12 0 __RU_l_____M_________________I___ referenced,uptodate,lru,mmap,readahead
    0x0000000000000868 192 0 ___U_lA____M_____________________ uptodate,lru,active,mmap
    0x0001000000000868 12 0 ___U_lA____M_________________I___ uptodate,lru,active,mmap,readahead
    0x000000000000086c 800 3 __RU_lA____M_____________________ referenced,uptodate,lru,active,mmap
    0x000100000000086c 31 0 __RU_lA____M_________________I___ referenced,uptodate,lru,active,mmap,readahead
    0x0000000000004878 2 0 ___UDlA____M__b__________________ uptodate,dirty,lru,active,mmap,swapbacked
    0x0000000000001000 492 1 ____________a____________________ anonymous
    0x0000000000005808 4 0 ___U_______Ma_b__________________ uptodate,mmap,anonymous,swapbacked
    0x0000000000005868 2839 11 ___U_lA____Ma_b__________________ uptodate,lru,active,mmap,anonymous,swapbacked
    0x000000000000586c 30 0 __RU_lA____Ma_b__________________ referenced,uptodate,lru,active,mmap,anonymous,swapbacked
    total 513968 2007

    # ./page-types -r
    flags page-count MB symbolic-flags long-symbolic-flags
    0x0000000000000000 468002 1828 _________________________________
    0x0000000100000000 19102 74 _____________________r___________ reserved
    0x0000000000008000 41 0 _______________H_________________ compound_head
    0x0000000000010000 188 0 ________________T________________ compound_tail
    0x0000000000008014 1 0 __R_D__________H_________________ referenced,dirty,compound_head
    0x0000000000010014 4 0 __R_D___________T________________ referenced,dirty,compound_tail
    0x0000000000000020 1 0 _____l___________________________ lru
    0x0000000800000024 34 0 __R__l__________________P________ referenced,lru,private
    0x0000000000000028 3794 14 ___U_l___________________________ uptodate,lru
    0x0001000000000028 46 0 ___U_l_______________________I___ uptodate,lru,readahead
    0x0000000400000028 44 0 ___U_l_________________d_________ uptodate,lru,mappedtodisk
    0x0001000400000028 2 0 ___U_l_________________d_____I___ uptodate,lru,mappedtodisk,readahead
    0x000000000000002c 6434 25 __RU_l___________________________ referenced,uptodate,lru
    0x000100000000002c 47 0 __RU_l_______________________I___ referenced,uptodate,lru,readahead
    0x000000040000002c 14 0 __RU_l_________________d_________ referenced,uptodate,lru,mappedtodisk
    0x000000080000002c 30 0 __RU_l__________________P________ referenced,uptodate,lru,private
    0x0000000800000040 8124 31 ______A_________________P________ active,private
    0x0000000000000040 219 0 ______A__________________________ active
    0x0000000800000060 1 0 _____lA_________________P________ lru,active,private
    0x0000000000000068 322 1 ___U_lA__________________________ uptodate,lru,active
    0x0001000000000068 12 0 ___U_lA______________________I___ uptodate,lru,active,readahead
    0x0000000400000068 13 0 ___U_lA________________d_________ uptodate,lru,active,mappedtodisk
    0x0000000800000068 12 0 ___U_lA_________________P________ uptodate,lru,active,private
    0x000000000000006c 977 3 __RU_lA__________________________ referenced,uptodate,lru,active
    0x000100000000006c 48 0 __RU_lA______________________I___ referenced,uptodate,lru,active,readahead
    0x000000040000006c 5 0 __RU_lA________________d_________ referenced,uptodate,lru,active,mappedtodisk
    0x000000080000006c 3 0 __RU_lA_________________P________ referenced,uptodate,lru,active,private
    0x0000000c0000006c 3 0 __RU_lA________________dP________ referenced,uptodate,lru,active,mappedtodisk,private
    0x0000000c00000068 1 0 ___U_lA________________dP________ uptodate,lru,active,mappedtodisk,private
    0x0000000000004078 1 0 ___UDlA_______b__________________ uptodate,dirty,lru,active,swapbacked
    0x000000000000407c 34 0 __RUDlA_______b__________________ referenced,uptodate,dirty,lru,active,swapbacked
    0x0000000000000400 538 2 __________B______________________ buddy
    0x0000000000000804 1 0 __R________M_____________________ referenced,mmap
    0x0000000000000828 1029 4 ___U_l_____M_____________________ uptodate,lru,mmap
    0x0001000000000828 43 0 ___U_l_____M_________________I___ uptodate,lru,mmap,readahead
    0x000000000000082c 382 1 __RU_l_____M_____________________ referenced,uptodate,lru,mmap
    0x000100000000082c 12 0 __RU_l_____M_________________I___ referenced,uptodate,lru,mmap,readahead
    0x0000000000000868 192 0 ___U_lA____M_____________________ uptodate,lru,active,mmap
    0x0001000000000868 12 0 ___U_lA____M_________________I___ uptodate,lru,active,mmap,readahead
    0x000000000000086c 800 3 __RU_lA____M_____________________ referenced,uptodate,lru,active,mmap
    0x000100000000086c 31 0 __RU_lA____M_________________I___ referenced,uptodate,lru,active,mmap,readahead
    0x0000000000004878 2 0 ___UDlA____M__b__________________ uptodate,dirty,lru,active,mmap,swapbacked
    0x0000000000001000 492 1 ____________a____________________ anonymous
    0x0000000000005008 2 0 ___U________a_b__________________ uptodate,anonymous,swapbacked
    0x0000000000005808 4 0 ___U_______Ma_b__________________ uptodate,mmap,anonymous,swapbacked
    0x000000000000580c 1 0 __RU_______Ma_b__________________ referenced,uptodate,mmap,anonymous,swapbacked
    0x0000000000005868 2839 11 ___U_lA____Ma_b__________________ uptodate,lru,active,mmap,anonymous,swapbacked
    0x000000000000586c 29 0 __RU_lA____Ma_b__________________ referenced,uptodate,lru,active,mmap,anonymous,swapbacked
    total 513968 2007

    # ./page-types --raw --list --no-summary --bits reserved
    offset count flags
    0 15 _____________________r___________
    31 4 _____________________r___________
    159 97 _____________________r___________
    4096 2067 _____________________r___________
    6752 2390 _____________________r___________
    9355 3 _____________________r___________
    9728 14526 _____________________r___________

    This patch:

    Introduce PageHuge(), which identifies huge/gigantic pages by their
    dedicated compound destructor functions.

    Also move prep_compound_gigantic_page() to hugetlb.c and make
    __free_pages_ok() non-static.

    Signed-off-by: Wu Fengguang
    Cc: KOSAKI Motohiro
    Cc: Andi Kleen
    Cc: Matt Mackall
    Cc: Alexey Dobriyan
    Cc: Ingo Molnar
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Wu Fengguang
     

11 Mar, 2009

1 commit

  • Fix kpf_copy_bit(src,dst) to be kpf_copy_bit(dst,src) to match the
    actual call patterns, e.g. kpf_copy_bit(kflags, KPF_LOCKED, PG_locked).

    This misplacement of src/dst only affected reporting of PG_writeback,
    PG_reclaim and PG_buddy. For others kflags==uflags so not affected.

    Signed-off-by: Wu Fengguang
    Reviewed-by: KOSAKI Motohiro
    Cc: stable@kernel.org
    Signed-off-by: Linus Torvalds

    Wu Fengguang
     

25 Feb, 2009

1 commit


23 Oct, 2008

1 commit