17 May, 2007

1 commit

  • Re-introduce rmap verification patches that Hugh removed when he removed
    PG_map_lock. PG_map_lock actually isn't needed to synchronise access to
    anonymous pages, because PG_locked and PTL together already do.

    These checks were important in discovering and fixing a rare rmap corruption
    in SLES9.

    Signed-off-by: Nick Piggin
    Cc: Hugh Dickins
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Nick Piggin
     

23 Dec, 2006

1 commit


08 Dec, 2006

2 commits

  • Replace all uses of kmem_cache_t with struct kmem_cache.

    The patch was generated using the following script:

    #!/bin/sh
    #
    # Replace one string by another in all the kernel sources.
    #

    set -e

    for file in `find * -name "*.c" -o -name "*.h"|xargs grep -l $1`; do
    quilt add $file
    sed -e "1,\$s/$1/$2/g" $file >/tmp/$$
    mv /tmp/$$ $file
    quilt refresh
    done

    The script was run like this

    sh replace kmem_cache_t "struct kmem_cache"

    Signed-off-by: Christoph Lameter
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Christoph Lameter
     
  • SLAB_KERNEL is an alias of GFP_KERNEL.

    Signed-off-by: Christoph Lameter
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Christoph Lameter
     

26 Sep, 2006

1 commit

  • Tracking of dirty pages in shared writeable mmap()s.

    The idea is simple: write protect clean shared writeable pages, catch the
    write-fault, make writeable and set dirty. On page write-back clean all the
    PTE dirty bits and write protect them once again.

    The implementation is a tad harder, mainly because the default
    backing_dev_info capabilities were too loosely maintained. Hence it is not
    enough to test the backing_dev_info for cap_account_dirty.

    The current heuristic is as follows, a VMA is eligible when:
    - its shared writeable
    (vm_flags & (VM_WRITE|VM_SHARED)) == (VM_WRITE|VM_SHARED)
    - it is not a 'special' mapping
    (vm_flags & (VM_PFNMAP|VM_INSERTPAGE)) == 0
    - the backing_dev_info is cap_account_dirty
    mapping_cap_account_dirty(vma->vm_file->f_mapping)
    - f_op->mmap() didn't change the default page protection

    Page from remap_pfn_range() are explicitly excluded because their COW
    semantics are already horrid enough (see vm_normal_page() in do_wp_page()) and
    because they don't have a backing store anyway.

    mprotect() is taught about the new behaviour as well. However it overrides
    the last condition.

    Cleaning the pages on write-back is done with page_mkclean() a new rmap call.
    It can be called on any page, but is currently only implemented for mapped
    pages, if the page is found the be of a VMA that accounts dirty pages it will
    also wrprotect the PTE.

    Finally, in fs/buffers.c:try_to_free_buffers(); remove clear_page_dirty() from
    under ->private_lock. This seems to be safe, since ->private_lock is used to
    serialize access to the buffers, not the page itself. This is needed because
    clear_page_dirty() will call into page_mkclean() and would thereby violate
    locking order.

    [dhowells@redhat.com: Provide a page_mkclean() implementation for NOMMU]
    Signed-off-by: Peter Zijlstra
    Cc: Hugh Dickins
    Signed-off-by: David Howells
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Peter Zijlstra
     

23 Jun, 2006

1 commit

  • Rip the page migration logic out.

    Remove all code that has to do with swapping during page migration.

    This also guts the ability to migrate pages to swap. No one used that so lets
    let it go for good.

    Page migration should be a bit broken after this patch.

    Signed-off-by: Christoph Lameter
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Christoph Lameter
     

26 Apr, 2006

1 commit


02 Feb, 2006

2 commits

  • Add remove_from_swap

    remove_from_swap() allows the restoration of the pte entries that existed
    before page migration occurred for anonymous pages by walking the reverse
    maps. This reduces swap use and establishes regular pte's without the need
    for page faults.

    Signed-off-by: Christoph Lameter
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Christoph Lameter
     
  • Add direct migration support with fall back to swap.

    Direct migration support on top of the swap based page migration facility.

    This allows the direct migration of anonymous pages and the migration of file
    backed pages by dropping the associated buffers (requires writeout).

    Fall back to swap out if necessary.

    The patch is based on lots of patches from the hotplug project but the code
    was restructured, documented and simplified as much as possible.

    Note that an additional patch that defines the migrate_page() method for
    filesystems is necessary in order to avoid writeback for anonymous and file
    backed pages.

    Signed-off-by: KAMEZAWA Hiroyuki
    Signed-off-by: Mike Kravetz
    Signed-off-by: Christoph Lameter
    Signed-off-by: Alexey Dobriyan
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Christoph Lameter
     

07 Jan, 2006

1 commit

  • Optimise rmap functions by minimising atomic operations when we know there
    will be no concurrent modifications.

    Signed-off-by: Nick Piggin
    Cc: Hugh Dickins
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Nick Piggin
     

29 Nov, 2005

1 commit

  • Some users (hi Zwane) have seen a problem when running a workload that
    eats nearly all of physical memory - th system does an OOM kill, even
    when there is still a lot of swap free.

    The problem appears to be a very big task that is holding the swap
    token, and the VM has a very hard time finding any other page in the
    system that is swappable.

    Instead of ignoring the swap token when sc->priority reaches 0, we could
    simply take the swap token away from the memory hog and make sure we
    don't give it back to the memory hog for a few seconds.

    This patch resolves the problem Zwane ran into.

    Signed-off-by: Rik van Riel
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Rik van Riel
     

30 Oct, 2005

1 commit

  • rmap's page_check_address descend without page_table_lock. First just
    pte_offset_map in case there's no pte present worth locking for, then take
    page_table_lock for the full check, and pass ptl back to caller in the same
    style as pte_offset_map_lock. __xip_unmap, page_referenced_one and
    try_to_unmap_one use pte_unmap_unlock. try_to_unmap_cluster also.

    page_check_address reformatted to avoid progressive indentation. No use is
    made of its one error code, return NULL when it fails.

    Signed-off-by: Hugh Dickins
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Hugh Dickins
     

24 Jun, 2005

1 commit

  • - generic_file* file operations do no longer have a xip/non-xip split
    - filemap_xip.c implements a new set of fops that require get_xip_page
    aop to work proper. all new fops are exported GPL-only (don't like to
    see whatever code use those except GPL modules)
    - __xip_unmap now uses page_check_address, which is no longer static
    in rmap.c, and defined in linux/rmap.h
    - mm/filemap.h is now much more clean, plainly having just Linus'
    inline funcs moved here from filemap.c
    - fix includes in filemap_xip to make it build cleanly on i386

    Signed-off-by: Carsten Otte
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Carsten Otte
     

17 Apr, 2005

1 commit

  • 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