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    SubjectRe: [BUG] SLOB's krealloc() seems bust
    Hi Matt,

    On Tue, Oct 7, 2008 at 8:13 PM, Matt Mackall <mpm@selenic.com> wrote:
    >> > @@ -515,7 +515,7 @@
    >> >
    >> > sp = (struct slob_page *)virt_to_page(block);
    >> > if (slob_page(sp))
    >> > - return ((slob_t *)block - 1)->units + SLOB_UNIT;
    >> > + return (((slob_t *)block - 1)->units - 1) * SLOB_UNIT;
    >>
    >> Hmm. I don't understand why we do the "minus one" thing here. Aren't
    >> we underestimating the size now?
    >
    > The first -1 takes us to the object header in front of the object
    > pointer. The second -1 subtracts out the size of the header.
    >
    > But it's entirely possible I'm off by one, so I'll double-check. Nick?

    Yeah, I was referring to the second subtraction. Looking at
    slob_page_alloc(), for example, we compare the return value of
    slob_units() to SLOB_UNITS(size), so I don't think we count the header
    in ->units. I mean, we ought to be seeing the subtraction elsewhere in
    the code as well, no?

    Pekka


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