Eric Lee / smarc-fsl-linux-kernel

14 Dec, 2014

2 commits

  • 031bc5743   mm/debug-pagealloc: make debug-pagealloc boottime configurable ... Browse Code »

    Now, we have prepared to avoid using debug-pagealloc in boottime. So
    introduce new kernel-parameter to disable debug-pagealloc in boottime, and
    makes related functions to be disabled in this case.

    Only non-intuitive part is change of guard page functions. Because guard
    page is effective only if debug-pagealloc is enabled, turning off
    according to debug-pagealloc is reasonable thing to do.

    Signed-off-by: Joonsoo Kim
    Cc: Mel Gorman
    Cc: Johannes Weiner
    Cc: Minchan Kim
    Cc: Dave Hansen
    Cc: Michal Nazarewicz
    Cc: Jungsoo Son
    Cc: Ingo Molnar
    Cc: Joonsoo Kim
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Joonsoo Kim
     
  • e30825f18   mm/debug-pagealloc: prepare boottime configurable on/off ... Browse Code »

    Until now, debug-pagealloc needs extra flags in struct page, so we need to
    recompile whole source code when we decide to use it. This is really
    painful, because it takes some time to recompile and sometimes rebuild is
    not possible due to third party module depending on struct page. So, we
    can't use this good feature in many cases.

    Now, we have the page extension feature that allows us to insert extra
    flags to outside of struct page. This gets rid of third party module
    issue mentioned above. And, this allows us to determine if we need extra
    memory for this page extension in boottime. With these property, we can
    avoid using debug-pagealloc in boottime with low computational overhead in
    the kernel built with CONFIG_DEBUG_PAGEALLOC. This will help our
    development process greatly.

    This patch is the preparation step to achive above goal. debug-pagealloc
    originally uses extra field of struct page, but, after this patch, it will
    use field of struct page_ext. Because memory for page_ext is allocated
    later than initialization of page allocator in CONFIG_SPARSEMEM, we should
    disable debug-pagealloc feature temporarily until initialization of
    page_ext. This patch implements this.

    Signed-off-by: Joonsoo Kim
    Cc: Mel Gorman
    Cc: Johannes Weiner
    Cc: Minchan Kim
    Cc: Dave Hansen
    Cc: Michal Nazarewicz
    Cc: Jungsoo Son
    Cc: Ingo Molnar
    Cc: Joonsoo Kim
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Joonsoo Kim
     

06 Dec, 2011

1 commit

  • 54c29c635   mm, x86: Remove debug_pagealloc_enabled ... Browse Code »

    When (no)bootmem finish operation, it pass pages to buddy
    allocator. Since debug_pagealloc_enabled is not set, we will do
    not protect pages, what is not what we want with
    CONFIG_DEBUG_PAGEALLOC=y.

    To fix remove debug_pagealloc_enabled. That variable was
    introduced by commit 12d6f21e "x86: do not PSE on
    CONFIG_DEBUG_PAGEALLOC=y" to get more CPA (change page
    attribude) code testing. But currently we have CONFIG_CPA_DEBUG,
    which test CPA.

    Signed-off-by: Stanislaw Gruszka
    Acked-by: Mel Gorman
    Cc: linux-mm@kvack.org
    Link: http://lkml.kernel.org/r/1322582711-14571-1-git-send-email-sgruszka@redhat.com
    Signed-off-by: Ingo Molnar

    Stanislaw Gruszka
     

01 Nov, 2011

3 commits

01 Apr, 2009

1 commit

  • 6a11f75b6   generic debug pagealloc ... Browse Code »

    CONFIG_DEBUG_PAGEALLOC is now supported by x86, powerpc, sparc64, and
    s390. This patch implements it for the rest of the architectures by
    filling the pages with poison byte patterns after free_pages() and
    verifying the poison patterns before alloc_pages().

    This generic one cannot detect invalid page accesses immediately but
    invalid read access may cause invalid dereference by poisoned memory and
    invalid write access can be detected after a long delay.

    Signed-off-by: Akinobu Mita
    Cc:
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Akinobu Mita