From 12779cdef8e394b74ba2249b2a5706b31a8239fe Mon Sep 17 00:00:00 2001
From: Bananymous <bananymousosq@gmail.com>
Date: Wed, 12 Apr 2023 00:22:08 +0300
Subject: [PATCH] Kernel: Threads now use only 4 KiB stack :)

---
 kernel/include/kernel/Thread.h | 4 ++++
 kernel/kernel/Process.cpp      | 5 +++--
 kernel/kernel/Thread.cpp       | 5 ++---
 3 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/kernel/include/kernel/Thread.h b/kernel/include/kernel/Thread.h
index 6e68fe81..e2bc306c 100644
--- a/kernel/include/kernel/Thread.h
+++ b/kernel/include/kernel/Thread.h
@@ -40,6 +40,9 @@ namespace Kernel
 		State state() const { return m_state; }
 		void terminate() { m_state = State::Terminating; }
 
+		uintptr_t stack_base() const { return (uintptr_t)m_stack_base; }
+		size_t stack_size() const { return m_stack_size; }
+
 		static Thread& current() ;
 		BAN::RefPtr<Process> process();
 
@@ -50,6 +53,7 @@ namespace Kernel
 		void on_exit();
 		
 	private:
+		static constexpr size_t m_stack_size = 4096 * 1;
 		void*		m_stack_base	= nullptr;
 		uintptr_t	m_rip			= 0;
 		uintptr_t	m_rsp			= 0;
diff --git a/kernel/kernel/Process.cpp b/kernel/kernel/Process.cpp
index 1236fb2f..cd7e09d5 100644
--- a/kernel/kernel/Process.cpp
+++ b/kernel/kernel/Process.cpp
@@ -9,10 +9,11 @@
 namespace Kernel
 {
 
+	static pid_t s_next_pid = 1;
+
 	BAN::ErrorOr<BAN::RefPtr<Process>> Process::create_kernel(entry_t entry, void* data)
 	{
-		static pid_t next_pid = 1;
-		auto process = TRY(BAN::RefPtr<Process>::create(next_pid++));
+		auto process = TRY(BAN::RefPtr<Process>::create(s_next_pid++));
 		TRY(process->m_working_directory.push_back('/'));
 		TRY(process->add_thread(entry, data));
 		return process;
diff --git a/kernel/kernel/Thread.cpp b/kernel/kernel/Thread.cpp
index db7cd34c..29502507 100644
--- a/kernel/kernel/Thread.cpp
+++ b/kernel/kernel/Thread.cpp
@@ -10,7 +10,6 @@
 namespace Kernel
 {
 
-	static constexpr size_t thread_stack_size = 16384;
 
 	template<size_t size, typename T>
 	static void write_to_stack(uintptr_t& rsp, const T& value)
@@ -45,10 +44,10 @@ namespace Kernel
 
 	BAN::ErrorOr<void> Thread::initialize(entry_t entry, void* data)
 	{
-		m_stack_base = kmalloc(thread_stack_size, PAGE_SIZE);
+		m_stack_base = kmalloc(m_stack_size, PAGE_SIZE);
 		if (m_stack_base == nullptr)
 			return BAN::Error::from_errno(ENOMEM);
-		m_rsp = (uintptr_t)m_stack_base + thread_stack_size;
+		m_rsp = (uintptr_t)m_stack_base + m_stack_size;
 		m_rip = (uintptr_t)entry;
 
 		write_to_stack<sizeof(void*)>(m_rsp, this);