citra/src/core/hle/kernel/thread.cpp
Subv 3d000c834b Kernel/Threads: Implement an SleepClientThread function for HLERequestContext-based services to make performing async tasks on the host while in an HLE service function easier.
An HLE service function that wants to perform an async operation should put the caller guest thread to sleep using SleepClientThread, passing in a callback to execute when the thread is resumed.
SleepClientThread returns a Kernel::Event that should be signaled to resume the guest thread when the host async operation completes.
2017-12-05 14:21:59 -05:00

527 lines
18 KiB
C++

// Copyright 2014 Citra Emulator Project / PPSSPP Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#include <algorithm>
#include <list>
#include <vector>
#include "common/assert.h"
#include "common/common_types.h"
#include "common/logging/log.h"
#include "common/math_util.h"
#include "common/thread_queue_list.h"
#include "core/arm/arm_interface.h"
#include "core/arm/skyeye_common/armstate.h"
#include "core/core.h"
#include "core/core_timing.h"
#include "core/hle/kernel/errors.h"
#include "core/hle/kernel/handle_table.h"
#include "core/hle/kernel/kernel.h"
#include "core/hle/kernel/memory.h"
#include "core/hle/kernel/mutex.h"
#include "core/hle/kernel/process.h"
#include "core/hle/kernel/thread.h"
#include "core/hle/result.h"
#include "core/memory.h"
namespace Kernel {
/// Event type for the thread wake up event
static CoreTiming::EventType* ThreadWakeupEventType = nullptr;
bool Thread::ShouldWait(Thread* thread) const {
return status != THREADSTATUS_DEAD;
}
void Thread::Acquire(Thread* thread) {
ASSERT_MSG(!ShouldWait(thread), "object unavailable!");
}
// TODO(yuriks): This can be removed if Thread objects are explicitly pooled in the future, allowing
// us to simply use a pool index or similar.
static Kernel::HandleTable wakeup_callback_handle_table;
// Lists all thread ids that aren't deleted/etc.
static std::vector<SharedPtr<Thread>> thread_list;
// Lists only ready thread ids.
static Common::ThreadQueueList<Thread*, THREADPRIO_LOWEST + 1> ready_queue;
static SharedPtr<Thread> current_thread;
// The first available thread id at startup
static u32 next_thread_id;
/**
* Creates a new thread ID
* @return The new thread ID
*/
inline static u32 const NewThreadId() {
return next_thread_id++;
}
Thread::Thread() {}
Thread::~Thread() {}
Thread* GetCurrentThread() {
return current_thread.get();
}
void Thread::Stop() {
// Cancel any outstanding wakeup events for this thread
CoreTiming::UnscheduleEvent(ThreadWakeupEventType, callback_handle);
wakeup_callback_handle_table.Close(callback_handle);
callback_handle = 0;
// Clean up thread from ready queue
// This is only needed when the thread is termintated forcefully (SVC TerminateProcess)
if (status == THREADSTATUS_READY) {
ready_queue.remove(current_priority, this);
}
status = THREADSTATUS_DEAD;
WakeupAllWaitingThreads();
// Clean up any dangling references in objects that this thread was waiting for
for (auto& wait_object : wait_objects) {
wait_object->RemoveWaitingThread(this);
}
wait_objects.clear();
// Release all the mutexes that this thread holds
ReleaseThreadMutexes(this);
// Mark the TLS slot in the thread's page as free.
u32 tls_page = (tls_address - Memory::TLS_AREA_VADDR) / Memory::PAGE_SIZE;
u32 tls_slot =
((tls_address - Memory::TLS_AREA_VADDR) % Memory::PAGE_SIZE) / Memory::TLS_ENTRY_SIZE;
Kernel::g_current_process->tls_slots[tls_page].reset(tls_slot);
}
/**
* Switches the CPU's active thread context to that of the specified thread
* @param new_thread The thread to switch to
*/
static void SwitchContext(Thread* new_thread) {
Thread* previous_thread = GetCurrentThread();
// Save context for previous thread
if (previous_thread) {
previous_thread->last_running_ticks = CoreTiming::GetTicks();
Core::CPU().SaveContext(previous_thread->context);
if (previous_thread->status == THREADSTATUS_RUNNING) {
// This is only the case when a reschedule is triggered without the current thread
// yielding execution (i.e. an event triggered, system core time-sliced, etc)
ready_queue.push_front(previous_thread->current_priority, previous_thread);
previous_thread->status = THREADSTATUS_READY;
}
}
// Load context of new thread
if (new_thread) {
ASSERT_MSG(new_thread->status == THREADSTATUS_READY,
"Thread must be ready to become running.");
// Cancel any outstanding wakeup events for this thread
CoreTiming::UnscheduleEvent(ThreadWakeupEventType, new_thread->callback_handle);
auto previous_process = Kernel::g_current_process;
current_thread = new_thread;
ready_queue.remove(new_thread->current_priority, new_thread);
new_thread->status = THREADSTATUS_RUNNING;
if (previous_process != current_thread->owner_process) {
Kernel::g_current_process = current_thread->owner_process;
SetCurrentPageTable(&Kernel::g_current_process->vm_manager.page_table);
}
Core::CPU().LoadContext(new_thread->context);
Core::CPU().SetCP15Register(CP15_THREAD_URO, new_thread->GetTLSAddress());
} else {
current_thread = nullptr;
// Note: We do not reset the current process and current page table when idling because
// technically we haven't changed processes, our threads are just paused.
}
}
/**
* Pops and returns the next thread from the thread queue
* @return A pointer to the next ready thread
*/
static Thread* PopNextReadyThread() {
Thread* next;
Thread* thread = GetCurrentThread();
if (thread && thread->status == THREADSTATUS_RUNNING) {
// We have to do better than the current thread.
// This call returns null when that's not possible.
next = ready_queue.pop_first_better(thread->current_priority);
if (!next) {
// Otherwise just keep going with the current thread
next = thread;
}
} else {
next = ready_queue.pop_first();
}
return next;
}
void WaitCurrentThread_Sleep() {
Thread* thread = GetCurrentThread();
thread->status = THREADSTATUS_WAIT_SLEEP;
}
void ExitCurrentThread() {
Thread* thread = GetCurrentThread();
thread->Stop();
thread_list.erase(std::remove(thread_list.begin(), thread_list.end(), thread),
thread_list.end());
}
/**
* Callback that will wake up the thread it was scheduled for
* @param thread_handle The handle of the thread that's been awoken
* @param cycles_late The number of CPU cycles that have passed since the desired wakeup time
*/
static void ThreadWakeupCallback(u64 thread_handle, int cycles_late) {
SharedPtr<Thread> thread = wakeup_callback_handle_table.Get<Thread>((Handle)thread_handle);
if (thread == nullptr) {
LOG_CRITICAL(Kernel, "Callback fired for invalid thread %08X", (Handle)thread_handle);
return;
}
if (thread->status == THREADSTATUS_WAIT_SYNCH_ANY ||
thread->status == THREADSTATUS_WAIT_SYNCH_ALL || thread->status == THREADSTATUS_WAIT_ARB ||
thread->status == THREADSTATUS_WAIT_HLE_EVENT) {
// Invoke the wakeup callback before clearing the wait objects
if (thread->wakeup_callback)
thread->wakeup_callback(ThreadWakeupReason::Timeout, thread, nullptr);
// Remove the thread from each of its waiting objects' waitlists
for (auto& object : thread->wait_objects)
object->RemoveWaitingThread(thread.get());
thread->wait_objects.clear();
}
thread->ResumeFromWait();
}
void Thread::WakeAfterDelay(s64 nanoseconds) {
// Don't schedule a wakeup if the thread wants to wait forever
if (nanoseconds == -1)
return;
CoreTiming::ScheduleEvent(nsToCycles(nanoseconds), ThreadWakeupEventType, callback_handle);
}
void Thread::ResumeFromWait() {
ASSERT_MSG(wait_objects.empty(), "Thread is waking up while waiting for objects");
switch (status) {
case THREADSTATUS_WAIT_SYNCH_ALL:
case THREADSTATUS_WAIT_SYNCH_ANY:
case THREADSTATUS_WAIT_HLE_EVENT:
case THREADSTATUS_WAIT_ARB:
case THREADSTATUS_WAIT_SLEEP:
case THREADSTATUS_WAIT_IPC:
break;
case THREADSTATUS_READY:
// The thread's wakeup callback must have already been cleared when the thread was first
// awoken.
ASSERT(wakeup_callback == nullptr);
// If the thread is waiting on multiple wait objects, it might be awoken more than once
// before actually resuming. We can ignore subsequent wakeups if the thread status has
// already been set to THREADSTATUS_READY.
return;
case THREADSTATUS_RUNNING:
DEBUG_ASSERT_MSG(false, "Thread with object id %u has already resumed.", GetObjectId());
return;
case THREADSTATUS_DEAD:
// This should never happen, as threads must complete before being stopped.
DEBUG_ASSERT_MSG(false, "Thread with object id %u cannot be resumed because it's DEAD.",
GetObjectId());
return;
}
wakeup_callback = nullptr;
ready_queue.push_back(current_priority, this);
status = THREADSTATUS_READY;
Core::System::GetInstance().PrepareReschedule();
}
/**
* Prints the thread queue for debugging purposes
*/
static void DebugThreadQueue() {
Thread* thread = GetCurrentThread();
if (!thread) {
LOG_DEBUG(Kernel, "Current: NO CURRENT THREAD");
} else {
LOG_DEBUG(Kernel, "0x%02X %u (current)", thread->current_priority,
GetCurrentThread()->GetObjectId());
}
for (auto& t : thread_list) {
u32 priority = ready_queue.contains(t.get());
if (priority != -1) {
LOG_DEBUG(Kernel, "0x%02X %u", priority, t->GetObjectId());
}
}
}
/**
* Finds a free location for the TLS section of a thread.
* @param tls_slots The TLS page array of the thread's owner process.
* Returns a tuple of (page, slot, alloc_needed) where:
* page: The index of the first allocated TLS page that has free slots.
* slot: The index of the first free slot in the indicated page.
* alloc_needed: Whether there's a need to allocate a new TLS page (All pages are full).
*/
std::tuple<u32, u32, bool> GetFreeThreadLocalSlot(std::vector<std::bitset<8>>& tls_slots) {
// Iterate over all the allocated pages, and try to find one where not all slots are used.
for (unsigned page = 0; page < tls_slots.size(); ++page) {
const auto& page_tls_slots = tls_slots[page];
if (!page_tls_slots.all()) {
// We found a page with at least one free slot, find which slot it is
for (unsigned slot = 0; slot < page_tls_slots.size(); ++slot) {
if (!page_tls_slots.test(slot)) {
return std::make_tuple(page, slot, false);
}
}
}
}
return std::make_tuple(0, 0, true);
}
/**
* Resets a thread context, making it ready to be scheduled and run by the CPU
* @param context Thread context to reset
* @param stack_top Address of the top of the stack
* @param entry_point Address of entry point for execution
* @param arg User argument for thread
*/
static void ResetThreadContext(ARM_Interface::ThreadContext& context, u32 stack_top,
u32 entry_point, u32 arg) {
memset(&context, 0, sizeof(ARM_Interface::ThreadContext));
context.cpu_registers[0] = arg;
context.pc = entry_point;
context.sp = stack_top;
context.cpsr = USER32MODE | ((entry_point & 1) << 5); // Usermode and THUMB mode
}
ResultVal<SharedPtr<Thread>> Thread::Create(std::string name, VAddr entry_point, u32 priority,
u32 arg, s32 processor_id, VAddr stack_top,
SharedPtr<Process> owner_process) {
// Check if priority is in ranged. Lowest priority -> highest priority id.
if (priority > THREADPRIO_LOWEST) {
LOG_ERROR(Kernel_SVC, "Invalid thread priority: %d", priority);
return ERR_OUT_OF_RANGE;
}
if (processor_id > THREADPROCESSORID_MAX) {
LOG_ERROR(Kernel_SVC, "Invalid processor id: %d", processor_id);
return ERR_OUT_OF_RANGE_KERNEL;
}
// TODO(yuriks): Other checks, returning 0xD9001BEA
if (!Memory::IsValidVirtualAddress(*owner_process, entry_point)) {
LOG_ERROR(Kernel_SVC, "(name=%s): invalid entry %08x", name.c_str(), entry_point);
// TODO: Verify error
return ResultCode(ErrorDescription::InvalidAddress, ErrorModule::Kernel,
ErrorSummary::InvalidArgument, ErrorLevel::Permanent);
}
SharedPtr<Thread> thread(new Thread);
thread_list.push_back(thread);
ready_queue.prepare(priority);
thread->thread_id = NewThreadId();
thread->status = THREADSTATUS_DORMANT;
thread->entry_point = entry_point;
thread->stack_top = stack_top;
thread->nominal_priority = thread->current_priority = priority;
thread->last_running_ticks = CoreTiming::GetTicks();
thread->processor_id = processor_id;
thread->wait_objects.clear();
thread->wait_address = 0;
thread->name = std::move(name);
thread->callback_handle = wakeup_callback_handle_table.Create(thread).Unwrap();
thread->owner_process = owner_process;
// Find the next available TLS index, and mark it as used
auto& tls_slots = owner_process->tls_slots;
bool needs_allocation = true;
u32 available_page; // Which allocated page has free space
u32 available_slot; // Which slot within the page is free
std::tie(available_page, available_slot, needs_allocation) = GetFreeThreadLocalSlot(tls_slots);
if (needs_allocation) {
// There are no already-allocated pages with free slots, lets allocate a new one.
// TLS pages are allocated from the BASE region in the linear heap.
MemoryRegionInfo* memory_region = GetMemoryRegion(MemoryRegion::BASE);
auto& linheap_memory = memory_region->linear_heap_memory;
if (linheap_memory->size() + Memory::PAGE_SIZE > memory_region->size) {
LOG_ERROR(Kernel_SVC,
"Not enough space in region to allocate a new TLS page for thread");
return ERR_OUT_OF_MEMORY;
}
size_t offset = linheap_memory->size();
// Allocate some memory from the end of the linear heap for this region.
linheap_memory->insert(linheap_memory->end(), Memory::PAGE_SIZE, 0);
memory_region->used += Memory::PAGE_SIZE;
owner_process->linear_heap_used += Memory::PAGE_SIZE;
tls_slots.emplace_back(0); // The page is completely available at the start
available_page = static_cast<u32>(tls_slots.size() - 1);
available_slot = 0; // Use the first slot in the new page
auto& vm_manager = owner_process->vm_manager;
vm_manager.RefreshMemoryBlockMappings(linheap_memory.get());
// Map the page to the current process' address space.
// TODO(Subv): Find the correct MemoryState for this region.
vm_manager.MapMemoryBlock(Memory::TLS_AREA_VADDR + available_page * Memory::PAGE_SIZE,
linheap_memory, offset, Memory::PAGE_SIZE, MemoryState::Private);
}
// Mark the slot as used
tls_slots[available_page].set(available_slot);
thread->tls_address = Memory::TLS_AREA_VADDR + available_page * Memory::PAGE_SIZE +
available_slot * Memory::TLS_ENTRY_SIZE;
// TODO(peachum): move to ScheduleThread() when scheduler is added so selected core is used
// to initialize the context
ResetThreadContext(thread->context, stack_top, entry_point, arg);
ready_queue.push_back(thread->current_priority, thread.get());
thread->status = THREADSTATUS_READY;
return MakeResult<SharedPtr<Thread>>(std::move(thread));
}
void Thread::SetPriority(u32 priority) {
ASSERT_MSG(priority <= THREADPRIO_LOWEST && priority >= THREADPRIO_HIGHEST,
"Invalid priority value.");
// If thread was ready, adjust queues
if (status == THREADSTATUS_READY)
ready_queue.move(this, current_priority, priority);
else
ready_queue.prepare(priority);
nominal_priority = current_priority = priority;
}
void Thread::UpdatePriority() {
u32 best_priority = nominal_priority;
for (auto& mutex : held_mutexes) {
if (mutex->priority < best_priority)
best_priority = mutex->priority;
}
BoostPriority(best_priority);
}
void Thread::BoostPriority(u32 priority) {
// If thread was ready, adjust queues
if (status == THREADSTATUS_READY)
ready_queue.move(this, current_priority, priority);
else
ready_queue.prepare(priority);
current_priority = priority;
}
SharedPtr<Thread> SetupMainThread(u32 entry_point, u32 priority, SharedPtr<Process> owner_process) {
// Initialize new "main" thread
auto thread_res =
Thread::Create("main", entry_point, priority, 0, owner_process->ideal_processor,
Memory::HEAP_VADDR_END, owner_process);
SharedPtr<Thread> thread = std::move(thread_res).Unwrap();
thread->context.fpscr =
FPSCR_DEFAULT_NAN | FPSCR_FLUSH_TO_ZERO | FPSCR_ROUND_TOZERO | FPSCR_IXC; // 0x03C00010
// Note: The newly created thread will be run when the scheduler fires.
return thread;
}
bool HaveReadyThreads() {
return ready_queue.get_first() != nullptr;
}
void Reschedule() {
Thread* cur = GetCurrentThread();
Thread* next = PopNextReadyThread();
if (cur && next) {
LOG_TRACE(Kernel, "context switch %u -> %u", cur->GetObjectId(), next->GetObjectId());
} else if (cur) {
LOG_TRACE(Kernel, "context switch %u -> idle", cur->GetObjectId());
} else if (next) {
LOG_TRACE(Kernel, "context switch idle -> %u", next->GetObjectId());
}
SwitchContext(next);
}
void Thread::SetWaitSynchronizationResult(ResultCode result) {
context.cpu_registers[0] = result.raw;
}
void Thread::SetWaitSynchronizationOutput(s32 output) {
context.cpu_registers[1] = output;
}
s32 Thread::GetWaitObjectIndex(WaitObject* object) const {
ASSERT_MSG(!wait_objects.empty(), "Thread is not waiting for anything");
auto match = std::find(wait_objects.rbegin(), wait_objects.rend(), object);
return static_cast<s32>(std::distance(match, wait_objects.rend()) - 1);
}
VAddr Thread::GetCommandBufferAddress() const {
// Offset from the start of TLS at which the IPC command buffer begins.
static constexpr int CommandHeaderOffset = 0x80;
return GetTLSAddress() + CommandHeaderOffset;
}
////////////////////////////////////////////////////////////////////////////////////////////////////
void ThreadingInit() {
ThreadWakeupEventType = CoreTiming::RegisterEvent("ThreadWakeupCallback", ThreadWakeupCallback);
current_thread = nullptr;
next_thread_id = 1;
}
void ThreadingShutdown() {
current_thread = nullptr;
for (auto& t : thread_list) {
t->Stop();
}
thread_list.clear();
ready_queue.clear();
}
const std::vector<SharedPtr<Thread>>& GetThreadList() {
return thread_list;
}
} // namespace Kernel