• Wu Fengguang's avatar
    mm: introduce PageHuge() for testing huge/gigantic pages · 20a0307c
    Wu Fengguang authored
    
    
    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: default avatarWu Fengguang <fengguang.wu@intel.com>
    Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
    Cc: Andi Kleen <andi@firstfloor.org>
    Cc: Matt Mackall <mpm@selenic.com>
    Cc: Alexey Dobriyan <adobriyan@gmail.com>
    Cc: Ingo Molnar <mingo@elte.hu>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    20a0307c
hugetlb.h 8.27 KB