thread_yield, thread_switch, etc. should reset the quantum?

[ghost]

I think we may need this but the project doc doesn't say explicitly.

The way we have it written currently, when thread_yield or anything that performs a context switch chooses a new thread, it doesn't give the new thread a fresh quantum, but instead keeps running on the old, partially expired quantum.

We might need to call setitimer() in every context switch

[elliott-beach]

If a running thread is suspended (discussed later) or yields
voluntarily, its remaining time slice will be abandoned

So the quantum should be reset by uthread_yield.