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> if (end > size) > return end; > - i = find_next_bit(map, end, index); > + i = find_last_bit_range(map, end, index); > if (i < end) { > start = i + 1; > goto again; If the only user of the API is in-house, I believe we can just move the 'map' pointer and decrease the 'end' accordingly: i = find_last_bit(map + BITS_TO_LONGS(index), end - round_down(index, BITS_PER_LONG)); That way you'll be able to bail out earlier just as well. (Not tested, just an illustration) Thanks, Yury