On Nov 25, 2013, at 11:53 AM, Yann Ylavic <[email protected]> wrote:
> On Mon, Nov 25, 2013 at 4:53 PM, Jim Jagielski <[email protected]> wrote: > > On Nov 25, 2013, at 10:24 AM, Yann Ylavic <[email protected]> wrote: > > > > > As Jeff said in the other thread, I think the test here should be : > > if (prev_idlers <= 1) > > that's because dec32 was returning the new value while add32 now returns > > the old one (fetch_and_sub vs sub_and_fetch). > > > > We aren't being consistent.. see below: > > > +static const apr_uint32_t zero_pt = ((apr_uint32_t)1 << 31); > > Hmmmm... for a 32bit int, shouldn't that be << 29 ?? > > I don't see, why 29? > Suppose idlers is 0: idlers - zero_pt == 0 - 2^31 == INT32_MIN; > and when idlers is 2^32-1: (2^32-1) - 2^31 == INT32_MAX. > Is there a need for more positives than negatives? All we are doing is trying to create a new offset... something between 0..INT32_MAX. Halfway is likely best, but we are talking scales here that it makes no real diff. In any case, ((apr_uint32_t)1 << 31) is wrong. Using <<30 would result in 1073741824 which is what we would want, if we want midway.
