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    Subject[PATCH mm v5 07/39] mm: clarify __GFP_ZEROTAGS comment
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    From: Andrey Konovalov <andreyknvl@google.com>

    __GFP_ZEROTAGS is intended as an optimization: if memory is zeroed during
    allocation, it's possible to set memory tags at the same time with little
    performance impact.

    Clarify this intention of __GFP_ZEROTAGS in the comment.

    Signed-off-by: Andrey Konovalov <andreyknvl@google.com>

    ---

    Changes v4->v5:
    - Mention optimization intention in the comment.
    ---
    include/linux/gfp.h | 6 ++++--
    1 file changed, 4 insertions(+), 2 deletions(-)

    diff --git a/include/linux/gfp.h b/include/linux/gfp.h
    index 5f893d994dcd..19e55f3fdd04 100644
    --- a/include/linux/gfp.h
    +++ b/include/linux/gfp.h
    @@ -228,8 +228,10 @@ struct vm_area_struct;
    *
    * %__GFP_ZERO returns a zeroed page on success.
    *
    - * %__GFP_ZEROTAGS returns a page with zeroed memory tags on success, if
    - * __GFP_ZERO is set.
    + * %__GFP_ZEROTAGS zeroes memory tags at allocation time if the memory itself
    + * is being zeroed (either via __GFP_ZERO or via init_on_alloc). This flag is
    + * intended for optimization: setting memory tags at the same time as zeroing
    + * memory has minimal additional performace impact.
    *
    * %__GFP_SKIP_KASAN_POISON returns a page which does not need to be poisoned
    * on deallocation. Typically used for userspace pages. Currently only has an
    --
    2.25.1
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