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    SubjectRE: [PATCH 2/9] lib/bitmap: implement bitmap_{empty,full} with bitmap_weight_eq()
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    From: Yury Norov
    > Sent: 14 December 2021 19:43
    ...
    >
    > I think that for long bitmaps the most time consuming operation is moving
    > data to L1, and for short bitmaps the difference between approaches is
    > barely measurable.
    >
    > But hweght_long on each iteration can't be more effective than the current
    > version. So, I'll drop this patch for v2 and keep things unchanged.

    Actually do bitmap_full/empty() calls make any sense at all?
    The result is stale since bitmaps are designed to do locked operations.
    If you have a lock covering the bitmap then you should be using
    something that uses non-locked accesses.
    Rightly or wrongly that isn't the bitmap api.

    David

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