kernel: Eliminate kernel global state

As means to pave the way for getting rid of global state within core,
This eliminates kernel global state by removing all globals. Instead
this introduces a KernelCore class which acts as a kernel instance. This
instance lives in the System class, which keeps its lifetime contained
to the lifetime of the System class.

This also forces the kernel types to actually interact with the main
kernel instance itself instead of having transient kernel state placed
all over several translation units, keeping everything together. It also
has a nice consequence of making dependencies much more explicit.

This also makes our initialization a tad bit more correct. Previously we
were creating a kernel process before the actual kernel was initialized,
which doesn't really make much sense.

The KernelCore class itself follows the PImpl idiom, which allows
keeping all the implementation details sealed away from everything else,
which forces the use of the exposed API and allows us to avoid any
unnecessary inclusions within the main kernel header.

1 files changed, 8 insertions, 14 deletions

diff --git a/src/core/hle/kernel/thread.h b/src/core/hle/kernel/thread.h
index 06edc296d..20f50458b 100644
--- a/src/core/hle/kernel/thread.h
+++ b/src/core/hle/kernel/thread.h
@@ -56,6 +56,7 @@ enum class ThreadWakeupReason {
 
 namespace Kernel {
 
+class KernelCore;
 class Process;
 class Scheduler;
 
@@ -63,6 +64,7 @@ class Thread final : public WaitObject {
 public:
     /**
      * Creates and returns a new thread. The new thread is immediately scheduled
+     * @param kernel The kernel instance this thread will be created under.
      * @param name The friendly name desired for the thread
      * @param entry_point The address at which the thread should start execution
      * @param priority The thread's priority
@@ -72,8 +74,9 @@ public:
      * @param owner_process The parent process for the thread
      * @return A shared pointer to the newly created thread
      */
-    static ResultVal<SharedPtr<Thread>> Create(std::string name, VAddr entry_point, u32 priority,
-                                               u64 arg, s32 processor_id, VAddr stack_top,
+    static ResultVal<SharedPtr<Thread>> Create(KernelCore& kernel, std::string name,
+                                               VAddr entry_point, u32 priority, u64 arg,
+                                               s32 processor_id, VAddr stack_top,
                                                SharedPtr<Process> owner_process);
 
     std::string GetName() const override {
@@ -263,7 +266,7 @@ public:
     u64 affinity_mask{0x1};
 
 private:
-    Thread();
+    explicit Thread(KernelCore& kernel);
     ~Thread() override;
 
     std::shared_ptr<std::vector<u8>> tls_memory = std::make_shared<std::vector<u8>>();
@@ -271,12 +274,13 @@ private:
 
 /**
  * Sets up the primary application thread
+ * @param kernel The kernel instance to create the main thread under.
  * @param entry_point The address at which the thread should start execution
  * @param priority The priority to give the main thread
  * @param owner_process The parent process for the main thread
  * @return A shared pointer to the main thread
  */
-SharedPtr<Thread> SetupMainThread(VAddr entry_point, u32 priority,
+SharedPtr<Thread> SetupMainThread(KernelCore& kernel, VAddr entry_point, u32 priority,
                                   SharedPtr<Process> owner_process);
 
 /**
@@ -294,14 +298,4 @@ void WaitCurrentThread_Sleep();
  */
 void ExitCurrentThread();
 
-/**
- * Initialize threading
- */
-void ThreadingInit();
-
-/**
- * Shutdown threading
- */
-void ThreadingShutdown();
-
 } // namespace Kernel