Muti Level feedback scheduling

Part 1: Multi-Level CPU Scheduler\r\nThe main purpose of this part is to add a new scheduling algorithm to GeekOS. As you might have already noticed, GeekOS uses a simple priority based preemptive Round Robin algorithm. In this project, you will change this to a multilevel feedback scheduling.\r\n\r\nYou are to augment the existing GeekOS Round Robin scheduling algorithm with a multilevel feedback scheduler (MLF). In Round Robin, all threads sit in a FIFO queue. In the MLF which you will implement, you will use 4 queues instead of one. Each queue is assigned a priority level, i.e. all threads in the same queue have the same priority. The queues will be numbered 0 through 3, with 0 being the highest priority, and 3 being the lowest. For this reason, s_runQueue in kthread.c has been changed from being a struct to being an array of structs, one for each priority level. Note that the queue priority level is distinct from the kthread priority field; the latter is used to choose which thread to run within a given queue (see below). Moreover, the highest priority level queue is numbered 0, while 0 is the lowest priority for a thread within a queue at a given level (see kthread.h).\r\n\r\nYou might want to review section 2.4.2 in the textbook that discusses Multiple Queues. Note, however that in our case the quantum is identical for all four queues.\r\n\r\nA newly created thread will be placed on the highest priority queue (i.e., 0). Each time a thread completes a full quantum, it will be placed on the run queue with the next lowest priority level, until it reaches priority level 3, at which point it can not go any lower. Hence, CPU-intensive threads will be eventually placed on the lowest priority level queue.