From 45d6caa1d08e8bd5811e2b906c72f2c04ca9d43e Mon Sep 17 00:00:00 2001
From: Bananymous <oskari.alaranta@bananymous.com>
Date: Sat, 9 Mar 2024 23:51:40 +0200
Subject: [PATCH] Kernel: APs now start their idle threads when scheduler is
 started

---
 kernel/include/kernel/Scheduler.h | 1 +
 kernel/kernel/Scheduler.cpp       | 8 +++++++-
 kernel/kernel/kernel.cpp          | 5 +++--
 3 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/kernel/include/kernel/Scheduler.h b/kernel/include/kernel/Scheduler.h
index 06ea0803..c2091d68 100644
--- a/kernel/include/kernel/Scheduler.h
+++ b/kernel/include/kernel/Scheduler.h
@@ -12,6 +12,7 @@ namespace Kernel
 	public:
 		static BAN::ErrorOr<void> initialize();
 		static Scheduler& get();
+		static bool is_started();
 
 		[[noreturn]] void start();
 
diff --git a/kernel/kernel/Scheduler.cpp b/kernel/kernel/Scheduler.cpp
index 3a3ad914..c68428bb 100644
--- a/kernel/kernel/Scheduler.cpp
+++ b/kernel/kernel/Scheduler.cpp
@@ -15,6 +15,7 @@ namespace Kernel
 	extern "C" [[noreturn]] void continue_thread(uintptr_t rsp, uintptr_t rip);
 
 	static Scheduler* s_instance = nullptr;
+	static BAN::Atomic<bool> s_started { false };
 
 	ALWAYS_INLINE static void load_temp_stack()
 	{
@@ -40,12 +41,17 @@ namespace Kernel
 	{
 		ASSERT(Processor::get_interrupt_state() == InterruptState::Disabled);
 		m_lock.lock();
-		ASSERT(!m_active_threads.empty());
+		s_started = true;
 		advance_current_thread();
 		execute_current_thread_locked();
 		ASSERT_NOT_REACHED();
 	}
 
+	bool Scheduler::is_started()
+	{
+		return s_started;
+	}
+
 	Thread& Scheduler::current_thread()
 	{
 		auto* current = Processor::get_current_thread();
diff --git a/kernel/kernel/kernel.cpp b/kernel/kernel/kernel.cpp
index 007b3246..238d1f8d 100644
--- a/kernel/kernel/kernel.cpp
+++ b/kernel/kernel/kernel.cpp
@@ -217,6 +217,7 @@ extern "C" void ap_main()
 
 	dprintln("ap{} initialized", Processor::current_id());
 
-	for (;;)
-		asm volatile("hlt");
+	while (!Scheduler::is_started())
+		__builtin_ia32_pause();
+	Scheduler::get().start();
 }