Provided are computing devices, each including a plurality of cores, and methods of allocating power to the plurality of cores. The computing device includes: a control core group including a plurality of control cores, the control core group configured to allocate a power budget to processing cores according to an energy management policy and state information of the processing cores, and transmit the allocated power budget to at least one of a lower control core and the processing cores; and a processing core group including at least one or more of the processing cores, the processing core group configured to perform computations based on the power budget allocated by the control core group, and transmit state information of the processing cores to the control core group, the state information of the processing cores having been modified based on the computations performed.