This commit: Implements CPU Interrupts, Replaces Cycle Timing for Host
Timing, Reworks the Kernel's Scheduler, Introduce Idle State and
Suspended State, Recreates the bootmanager, Initializes Multicore
system.
This commit corrects an error in which a Core could remain with an
exclusive state after running, leaving space for possible race
conditions between changing cores.
Uncovered a bug within Thread's SetCoreAndAffinityMask() where an
unsigned variable (ideal_core) was being compared against "< 0", which
would always be a false condition.
We can also get rid of an unused function (GetNextProcessorId) which contained a sign
mismatch warning.
In case of redundant yields, the scheduler will now idle the core for
it's timeslice, in order to avoid continuously yielding the same thing
over and over.
Since C++17, we no longer need to explicitly specify the type of the
mutex within the lock_guard. The type system can now deduce these with
deduction guides.
Rather than make a global accessor for this sort of thing. We can make
it a part of the thread interface itself. This allows getting rid of a
hidden global accessor in the kernel code.
Avoids directly relying on the global system instance and instead makes
an arbitrary system instance an explicit dependency on construction.
This also allows removing dependencies on some global accessor functions
as well.
Gets rid of the largest set of mutable global state within the core.
This also paves a way for eliminating usages of GetInstance() on the
System class as a follow-up.
Note that no behavioral changes have been made, and this simply extracts
the functionality into a class. This also has the benefit of making
dependencies on the core timing functionality explicit within the
relevant interfaces.
Places all of the timing-related functionality under the existing Core
namespace to keep things consistent, rather than having the timing
utilities sitting in its own completely separate namespace.
