cpu scheduler: make _reciprocal_shares_times_2_32 wider to avoid overflow problems
cpu scheduler: make _reciprocal_shares_times_2_32 wider to avoid overflow problems

reciprocal shares calculation[1] results in overflow if shares is 1.0f, which
will later mess with calculation of vruntime.

[1]: _reciprocal_shares_times_2_power_32((uint64_t(1) << 32) / _shares)

Signed-off-by: Raphael S. Carvalho <1e2942cea40e3b4d2162dfcd9e53e41c05a84d22@scylladb.com>
Message-Id: <20171013175609.7021-1-1e2942cea40e3b4d2162dfcd9e53e41c05a84d22@scylladb.com>

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