Doug / smarc-fsl-linux-kernel

03 May, 2009

1 commit

  • 00a62ce91   mm: fix Committed_AS underflow on large NR_CPUS environment ... Browse Code »

    The Committed_AS field can underflow in certain situations:

    > # while true; do cat /proc/meminfo | grep _AS; sleep 1; done | uniq -c
    > 1 Committed_AS: 18446744073709323392 kB
    > 11 Committed_AS: 18446744073709455488 kB
    > 6 Committed_AS: 35136 kB
    > 5 Committed_AS: 18446744073709454400 kB
    > 7 Committed_AS: 35904 kB
    > 3 Committed_AS: 18446744073709453248 kB
    > 2 Committed_AS: 34752 kB
    > 9 Committed_AS: 18446744073709453248 kB
    > 8 Committed_AS: 34752 kB
    > 3 Committed_AS: 18446744073709320960 kB
    > 7 Committed_AS: 18446744073709454080 kB
    > 3 Committed_AS: 18446744073709320960 kB
    > 5 Committed_AS: 18446744073709454080 kB
    > 6 Committed_AS: 18446744073709320960 kB

    Because NR_CPUS can be greater than 1000 and meminfo_proc_show() does
    not check for underflow.

    But NR_CPUS proportional isn't good calculation. In general,
    possibility of lock contention is proportional to the number of online
    cpus, not theorical maximum cpus (NR_CPUS).

    The current kernel has generic percpu-counter stuff. using it is right
    way. it makes code simplify and percpu_counter_read_positive() don't
    make underflow issue.

    Reported-by: Dave Hansen
    Signed-off-by: KOSAKI Motohiro
    Cc: Eric B Munson
    Cc: Mel Gorman
    Cc: Christoph Lameter
    Cc: [All kernel versions]
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    KOSAKI Motohiro
     

09 Jul, 2008

1 commit

  • b845f313d   mm: Allow architectures to define additional protection bits ... Browse Code »

    This patch allows architectures to define functions to deal with
    additional protections bits for mmap() and mprotect().

    arch_calc_vm_prot_bits() maps additonal protection bits to vm_flags
    arch_vm_get_page_prot() maps additional vm_flags to the vma's vm_page_prot
    arch_validate_prot() checks for valid values of the protection bits

    Note: vm_get_page_prot() is now pretty ugly, but the generated code
    should be identical for architectures that don't define additional
    protection bits.

    Signed-off-by: Dave Kleikamp
    Acked-by: Andrew Morton
    Acked-by: Hugh Dickins
    Signed-off-by: Benjamin Herrenschmidt

    Dave Kleikamp
     

25 May, 2008

1 commit

  • 80119ef5c   mm: fix atomic_t overflow in vm ... Browse Code »

    The atomic_t type is 32bit but a 64bit system can have more than 2^32
    pages of virtual address space available. Without this we overflow on
    ludicrously large mappings

    Signed-off-by: Alan Cox
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Alan Cox
     

26 Apr, 2006

1 commit

25 Apr, 2006

1 commit

17 Apr, 2005

1 commit

  • 1da177e4c   Linux-2.6.12-rc2 ... Browse Code »

    Initial git repository build. I'm not bothering with the full history,
    even though we have it. We can create a separate "historical" git
    archive of that later if we want to, and in the meantime it's about
    3.2GB when imported into git - space that would just make the early
    git days unnecessarily complicated, when we don't have a lot of good
    infrastructure for it.

    Let it rip!

    Linus Torvalds