The execution context of a sub-process thread. More...

#include <process.h>

Public Member Functions
	Thread (void(_entry_point)(void ), void args, int arg_amount, Process parent)
	Constructor for the Thread class.

	~Thread ()
	Destructor for the Thread class.

void	sleep (size_t milliseconds)
	Sleeps the thread for a certain amount of time.

void	yield ()
	Pass execution to the next ready thread.

uintptr_t	tss_pointer () const
	Gets the stack pointer to use for the TSS when switching to this thread.

void	set_tss_pointer (uintptr_t new_tss_pointer)
	Sets the stack pointer to use for the TSS when switching to this thread.

void	save_sse_state ()
	Saves the SSE, x87 FPU, and MMX states from memory to the thread.

void	restore_sse_state ()
	Restores the SSE, x87 FPU, and MMX states from the thread to memory.

void	save_cpu_state ()
	Saves the CPU state into the thread's execution_state structure.

void	enable_port (uint64_t port)
	Sets bits in the threads TSS to allow a port for I/O.

void	disable_port (uint64_t port)
	Sets bits in the threads TSS to disallow a port for I/O.

void	load_port_bitmap ()
	Copy this ports.

Public Attributes
uint64_t	tid
	The thread ID.

uint64_t	parent_pid
	The parent process ID.

volatile system::cpu_status_t	execution_state
	The CPU state of the thread.

volatile thread_state_t	thread_state
	The current state of the thread.

volatile size_t	ticks
	The number of ticks the thread has run for.

volatile size_t	wakeup_time
	The time at which the thread should wake up (if sleeping)

Detailed Description

The execution context of a sub-process thread.

Todo:: io bitmap per process instead

Definition at line 50 of file process.h.

Constructor & Destructor Documentation

◆ Thread()

Thread::Thread	(	void()(void )	_entry_point,
		void *	args,
		int	arg_amount,
		Process *	parent
	)

Constructor for the Thread class.

Parameters

_entry_point	The address of the function to start executing
args	The arguments to pass to the function
arg_amount	The number of arguments
parent	The proccess that owns this thread (started it)

Todo:: Cant use rsp0 for kernel stack storage as once scheduler starts up it may point to a userspace rsp0 (nor is it good to use the same stack for every process)

Warning: cant usee global MemoryManager::malloc() during constructor as process hasn't been registered with the scheduler yet

Definition at line 32 of file process.cpp.

{
 
    // Basic setup
    thread_state = ThreadState::NEW;
    wakeup_time = 0;
    ticks = 0;
 
    // Create the stack ()
    m_stack_pointer = (uintptr_t) parent->memory_manager->allocate(STACK_SIZE) + STACK_SIZE;
 
    // Use the kernel stack
    m_tss_stack_pointer = parent->is_kernel ? CPU::executing_core() -> tss.rsp0 : (uintptr_t) parent->memory_manager->kmalloc(STACK_SIZE) + STACK_SIZE;
 
    // Mak sure there is a stack
    ASSERT(m_stack_pointer != 0 && m_tss_stack_pointer != 0, "Failed to allocate stack for thread");
 
    // Set up the execution state
    execution_state = {};
    execution_state.rip = (uint64_t) _entry_point;
    execution_state.ss = parent->is_kernel ? 0x10 : 0x23;
    execution_state.cs = parent->is_kernel ? 0x8 : 0x1B;
    execution_state.rflags = 0x202;
    execution_state.interrupt_number = 0;
    execution_state.error_code = 0;
    execution_state.rsp = m_stack_pointer;
    execution_state.rbp = 0;
 
    // Copy the args into userspace
    uint64_t argc = arg_amount;
    size_t arg_size = argc * sizeof(void*);
    void* argv = parent->memory_manager->allocate(arg_size);
    for (int i = 0; i < argc; i++) {
 
        // Copy each argument
        size_t len = strlen(((char**)args)[i]) + 1;
        ((char**)argv)[i] = (char*) parent->memory_manager->allocate(len);
        memcpy(((char**)argv)[i], ((char**)args)[i], len);
    }
 
    execution_state.rdi = argc;
    execution_state.rsi = (uint64_t) argv;
    //execution_state->rdx = (uint64_t)env_args;
 
    // All ports denied by default
    memset(m_io_bitmap, 0xFF, sizeof(m_io_bitmap));
 
    parent_pid = parent->pid();
}

References MaxOS::memory::allocator::BumpAllocator::allocate(), MaxOS::system::CPU::executing_core(), execution_state, MaxOS::processes::Process::is_kernel, MaxOS::memory::MemoryManager::kmalloc(), MaxOS::processes::Process::memory_manager, parent_pid, MaxOS::processes::Process::pid(), MaxOS::processes::STACK_SIZE, thread_state, ticks, and wakeup_time.

Member Function Documentation

◆ disable_port()

void Thread::disable_port ( uint64_t port )

Sets bits in the threads TSS to disallow a port for I/O.

Definition at line 258 of file process.cpp.

                                       {
 
    // Disable the port
    m_io_bitmap[port / 8] |= (1U << (port % 8));
    load_port_bitmap();
}

References load_port_bitmap().

Referenced by MaxOS::processes::resources::ThreadResource::write().

◆ enable_port()

void Thread::enable_port ( uint64_t port )

Sets bits in the threads TSS to allow a port for I/O.

Definition at line 247 of file process.cpp.

                                      {
 
    // Enable the port
    m_io_bitmap[port / 8] &= ~(1U << (port % 8));
    load_port_bitmap();
 
}

References load_port_bitmap().

Referenced by MaxOS::processes::resources::ThreadResource::write().

◆ load_port_bitmap()

void Thread::load_port_bitmap ( )

Copy this ports.

Definition at line 268 of file process.cpp.

                              {
 
    memcpy(CPU::executing_core()->tss.io_bitmap, &m_io_bitmap, sizeof(m_io_bitmap));
 
}

References MaxOS::system::CPU::executing_core().

Referenced by disable_port(), and enable_port().

◆ restore_sse_state()

void Thread::restore_sse_state ( )

Restores the SSE, x87 FPU, and MMX states from the thread to memory.

Definition at line 138 of file process.cpp.

                               {
 
    // Ensure the state saving is enabled
    if (!CPU::executing_core()->xsave_enabled)
        return;
 
    // Restore the state
    asm volatile("fxrstor %0" : : "m" (m_sse_save_region));
}

References MaxOS::system::CPU::executing_core().

◆ save_cpu_state()

void Thread::save_cpu_state ( )

Saves the CPU state into the thread's execution_state structure.

Definition at line 240 of file process.cpp.

                            {
    save_cpu_state_naked(&execution_state);
}

References execution_state, and save_cpu_state_naked().

Referenced by yield().

◆ save_sse_state()

void Thread::save_sse_state ( )

Saves the SSE, x87 FPU, and MMX states from memory to the thread.

Definition at line 125 of file process.cpp.

                            {
 
    // Ensure the state saving is enabled
    if (!CPU::executing_core()->xsave_enabled)
        return;
 
    // Save the state
    asm volatile("fxsave %0" : "=m" (m_sse_save_region));
}

References MaxOS::system::CPU::executing_core().

Referenced by MaxOS::processes::Scheduler::schedule_next().

◆ set_tss_pointer()

void MaxOS::processes::Thread::set_tss_pointer ( uintptr_t new_tss_pointer )

inline

Sets the stack pointer to use for the TSS when switching to this thread.

Definition at line 78 of file process.h.

◆ sleep()

void Thread::sleep ( size_t milliseconds )

Sleeps the thread for a certain amount of time.

Parameters

milliseconds The amount of time to sleep for

Definition at line 92 of file process.cpp.

                                      {
 
    // Update the state
    thread_state = ThreadState::SLEEPING;
    wakeup_time  = milliseconds;
    yield();
}

References thread_state, wakeup_time, and yield().

Referenced by MaxOS::processes::resources::ThreadResource::write().

◆ tss_pointer()

uintptr_t MaxOS::processes::Thread::tss_pointer ( ) const

inline

Gets the stack pointer to use for the TSS when switching to this thread.

Returns: tss

Definition at line 77 of file process.h.

◆ yield()

void Thread::yield ( )

Pass execution to the next ready thread.

Definition at line 103 of file process.cpp.

                   {
 
    // Only update the state if the caller hasn't specified the resume condition state
    if (thread_state == ThreadState::RUNNING)
        thread_state = ThreadState::READY;
 
    // Save a checkpoint (resumed state is ret of the below function: execution after yield will be there)
    save_cpu_state();
 
    // Schedule the replacement thread, but guard against infinite loops where thread continusly pass execution to the
    // next thread after scheduler resumes it post yield)
    if(thread_state != ThreadState::RUNNING){
 
        // Yield to the next thread
        cpu_status_t* next = GlobalScheduler::core_scheduler()->schedule_next(&execution_state);
        InterruptManager::ForceInterruptReturn(next);
    }
}

References MaxOS::processes::GlobalScheduler::core_scheduler(), execution_state, MaxOS::hardwarecommunication::InterruptManager::ForceInterruptReturn(), save_cpu_state(), MaxOS::processes::Scheduler::schedule_next(), and thread_state.

Referenced by MaxOS::runtime::TrapFlagExcpetion::handle_interrupt(), MaxOS::runtime::BreakPointException::handle_interrupt(), MaxOS::processes::SharedMessageEndpoint::read(), MaxOS::processes::resources::BridgeHandler::send_to_bridge(), sleep(), and MaxOS::processes::resources::ThreadResource::write().

Member Data Documentation

◆ execution_state

volatile system::cpu_status_t MaxOS::processes::Thread::execution_state

The CPU state of the thread.

Definition at line 71 of file process.h.

Referenced by MaxOS::runtime::GDBServer::attach(), MaxOS::runtime::GDBServer::handle_step_instruction(), save_cpu_state(), MaxOS::processes::Scheduler::schedule_next(), Thread(), and yield().

◆ parent_pid

uint64_t MaxOS::processes::Thread::parent_pid

The parent process ID.

Definition at line 69 of file process.h.

Referenced by MaxOS::processes::Process::add_thread(), MaxOS::processes::Scheduler::current_process(), MaxOS::runtime::GDBServer::handle_remove_breakpoint(), MaxOS::runtime::GDBServer::handle_set_breakpoint(), MaxOS::processes::resources::ThreadResource::read(), MaxOS::processes::Scheduler::schedule_next(), MaxOS::runtime::GDBServer::send_memory(), and Thread().

◆ thread_state

volatile thread_state_t MaxOS::processes::Thread::thread_state

The current state of the thread.

Definition at line 72 of file process.h.

Referenced by MaxOS::runtime::GDBServer::attach(), MaxOS::processes::resources::ThreadResource::close(), MaxOS::runtime::GDBServer::handle_continue(), MaxOS::runtime::GDBServer::handle_detach(), MaxOS::runtime::TrapFlagExcpetion::handle_interrupt(), MaxOS::runtime::BreakPointException::handle_interrupt(), MaxOS::runtime::GDBServer::handle_step_instruction(), MaxOS::processes::resources::ThreadResource::read(), MaxOS::processes::BlockingLock::release(), MaxOS::processes::Scheduler::remove_process(), MaxOS::processes::Scheduler::schedule_next(), sleep(), Thread(), MaxOS::processes::resources::ThreadResource::write(), and yield().

◆ ticks

volatile size_t MaxOS::processes::Thread::ticks

The number of ticks the thread has run for.

Definition at line 74 of file process.h.

Referenced by MaxOS::processes::resources::ThreadResource::read(), MaxOS::processes::Scheduler::schedule(), and Thread().

◆ tid

uint64_t MaxOS::processes::Thread::tid

The thread ID.

Definition at line 68 of file process.h.

Referenced by MaxOS::processes::Scheduler::add_process(), MaxOS::processes::Scheduler::add_thread(), MaxOS::processes::Scheduler::force_remove_process(), MaxOS::processes::Scheduler::get_thread(), MaxOS::processes::resources::ThreadResource::read(), and MaxOS::processes::Scheduler::schedule_next().

◆ wakeup_time

volatile size_t MaxOS::processes::Thread::wakeup_time

The time at which the thread should wake up (if sleeping)

Definition at line 75 of file process.h.

Referenced by MaxOS::processes::resources::ThreadResource::read(), MaxOS::processes::Scheduler::schedule_next(), sleep(), and Thread().

The documentation for this class was generated from the following files:

/home/runner/work/MaxOS/MaxOS/kernel/include/processes/process.h
/home/runner/work/MaxOS/MaxOS/kernel/src/processes/process.cpp

Public Member Functions

Public Attributes

Detailed Description

Constructor & Destructor Documentation

◆ Thread()

Member Function Documentation

◆ disable_port()

◆ enable_port()

◆ load_port_bitmap()

◆ restore_sse_state()

◆ save_cpu_state()

◆ save_sse_state()

◆ set_tss_pointer()

◆ sleep()

◆ tss_pointer()

◆ yield()

Member Data Documentation

◆ execution_state

◆ parent_pid

◆ thread_state

◆ ticks

◆ tid

◆ wakeup_time