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Merge pull request #2393 from Subv/synch

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Kernel: Mutex priority inheritance and synchronization improvements.
This commit is contained in:
Sebastian Valle 2017-01-05 12:55:01 -05:00 committed by GitHub
commit f20d872643
18 changed files with 227 additions and 162 deletions
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9
src/citra_qt/debugger/wait_tree.cpp
View file

@ -153,7 +153,8 @@ QString WaitTreeThread::GetText() const {
case THREADSTATUS_WAIT_SLEEP:
status = tr("sleeping");
break;
case THREADSTATUS_WAIT_SYNCH:
case THREADSTATUS_WAIT_SYNCH_ALL:
case THREADSTATUS_WAIT_SYNCH_ANY:
status = tr("waiting for objects");
break;
case THREADSTATUS_DORMANT:
@ -180,7 +181,8 @@ QColor WaitTreeThread::GetColor() const {
return QColor(Qt::GlobalColor::darkRed);
case THREADSTATUS_WAIT_SLEEP:
return QColor(Qt::GlobalColor::darkYellow);
case THREADSTATUS_WAIT_SYNCH:
case THREADSTATUS_WAIT_SYNCH_ALL:
case THREADSTATUS_WAIT_SYNCH_ANY:
return QColor(Qt::GlobalColor::red);
case THREADSTATUS_DORMANT:
return QColor(Qt::GlobalColor::darkCyan);
@ -228,7 +230,8 @@ std::vector<std::unique_ptr<WaitTreeItem>> WaitTreeThread::GetChildren() const {
} else {
list.push_back(std::make_unique<WaitTreeMutexList>(thread.held_mutexes));
}
if (thread.status == THREADSTATUS_WAIT_SYNCH) {
if (thread.status == THREADSTATUS_WAIT_SYNCH_ANY ||
thread.status == THREADSTATUS_WAIT_SYNCH_ALL) {
list.push_back(std::make_unique<WaitTreeObjectList>(thread.wait_objects,
thread.IsSleepingOnWaitAll()));
}

6
src/core/hle/kernel/event.cpp
View file

@ -30,12 +30,12 @@ SharedPtr<Event> Event::Create(ResetType reset_type, std::string name) {
return evt;
}
bool Event::ShouldWait() {
bool Event::ShouldWait(Thread* thread) const {
return !signaled;
}
void Event::Acquire() {
ASSERT_MSG(!ShouldWait(), "object unavailable!");
void Event::Acquire(Thread* thread) {
ASSERT_MSG(!ShouldWait(thread), "object unavailable!");
// Release the event if it's not sticky...
if (reset_type != ResetType::Sticky)

4
src/core/hle/kernel/event.h
View file

@ -35,8 +35,8 @@ public:
bool signaled; ///< Whether the event has already been signaled
std::string name; ///< Name of event (optional)
bool ShouldWait() override;
void Acquire() override;
bool ShouldWait(Thread* thread) const override;
void Acquire(Thread* thread) override;
void Signal();
void Clear();

49
src/core/hle/kernel/kernel.cpp
View file

@ -3,7 +3,6 @@
// Refer to the license.txt file included.
#include <algorithm>
#include <boost/range/algorithm_ext/erase.hpp>
#include "common/assert.h"
#include "common/logging/log.h"
#include "core/hle/config_mem.h"
@ -28,32 +27,39 @@ void WaitObject::AddWaitingThread(SharedPtr<Thread> thread) {
void WaitObject::RemoveWaitingThread(Thread* thread) {
auto itr = std::find(waiting_threads.begin(), waiting_threads.end(), thread);
// If a thread passed multiple handles to the same object,
// the kernel might attempt to remove the thread from the object's
// waiting threads list multiple times.
if (itr != waiting_threads.end())
waiting_threads.erase(itr);
}
SharedPtr<Thread> WaitObject::GetHighestPriorityReadyThread() {
// Remove the threads that are ready or already running from our waitlist
boost::range::remove_erase_if(waiting_threads, [](const SharedPtr<Thread>& thread) {
return thread->status == THREADSTATUS_RUNNING || thread->status == THREADSTATUS_READY ||
thread->status == THREADSTATUS_DEAD;
});
// TODO(Subv): This call should be performed inside the loop below to check if an object can be
// acquired by a particular thread. This is useful for things like recursive locking of Mutexes.
if (ShouldWait())
return nullptr;
Thread* candidate = nullptr;
s32 candidate_priority = THREADPRIO_LOWEST + 1;
for (const auto& thread : waiting_threads) {
// The list of waiting threads must not contain threads that are not waiting to be awakened.
ASSERT_MSG(thread->status == THREADSTATUS_WAIT_SYNCH_ANY ||
thread->status == THREADSTATUS_WAIT_SYNCH_ALL,
"Inconsistent thread statuses in waiting_threads");
if (thread->current_priority >= candidate_priority)
continue;
bool ready_to_run =
std::none_of(thread->wait_objects.begin(), thread->wait_objects.end(),
[](const SharedPtr<WaitObject>& object) { return object->ShouldWait(); });
if (ShouldWait(thread.get()))
continue;
// A thread is ready to run if it's either in THREADSTATUS_WAIT_SYNCH_ANY or
// in THREADSTATUS_WAIT_SYNCH_ALL and the rest of the objects it is waiting on are ready.
bool ready_to_run = true;
if (thread->status == THREADSTATUS_WAIT_SYNCH_ALL) {
ready_to_run = std::none_of(thread->wait_objects.begin(), thread->wait_objects.end(),
[&thread](const SharedPtr<WaitObject>& object) {
return object->ShouldWait(thread.get());
});
}
if (ready_to_run) {
candidate = thread.get();
candidate_priority = thread->current_priority;
@ -66,7 +72,7 @@ SharedPtr<Thread> WaitObject::GetHighestPriorityReadyThread() {
void WaitObject::WakeupAllWaitingThreads() {
while (auto thread = GetHighestPriorityReadyThread()) {
if (!thread->IsSleepingOnWaitAll()) {
Acquire();
Acquire(thread.get());
// Set the output index of the WaitSynchronizationN call to the index of this object.
if (thread->wait_set_output) {
thread->SetWaitSynchronizationOutput(thread->GetWaitObjectIndex(this));
@ -74,18 +80,17 @@ void WaitObject::WakeupAllWaitingThreads() {
}
} else {
for (auto& object : thread->wait_objects) {
object->Acquire();
object->RemoveWaitingThread(thread.get());
object->Acquire(thread.get());
}
// Note: This case doesn't update the output index of WaitSynchronizationN.
// Clear the thread's waitlist
thread->wait_objects.clear();
}
for (auto& object : thread->wait_objects)
object->RemoveWaitingThread(thread.get());
thread->wait_objects.clear();
thread->SetWaitSynchronizationResult(RESULT_SUCCESS);
thread->ResumeFromWait();
// Note: Removing the thread from the object's waitlist will be
// done by GetHighestPriorityReadyThread.
}
}

13
src/core/hle/kernel/kernel.h
View file

@ -132,25 +132,26 @@ using SharedPtr = boost::intrusive_ptr<T>;
class WaitObject : public Object {
public:
/**
* Check if the current thread should wait until the object is available
* Check if the specified thread should wait until the object is available
* @param thread The thread about which we're deciding.
* @return True if the current thread should wait due to this object being unavailable
*/
virtual bool ShouldWait() = 0;
virtual bool ShouldWait(Thread* thread) const = 0;
/// Acquire/lock the object if it is available
virtual void Acquire() = 0;
/// Acquire/lock the object for the specified thread if it is available
virtual void Acquire(Thread* thread) = 0;
/**
* Add a thread to wait on this object
* @param thread Pointer to thread to add
*/
void AddWaitingThread(SharedPtr<Thread> thread);
virtual void AddWaitingThread(SharedPtr<Thread> thread);
/**
* Removes a thread from waiting on this object (e.g. if it was resumed already)
* @param thread Pointer to thread to remove
*/
void RemoveWaitingThread(Thread* thread);
virtual void RemoveWaitingThread(Thread* thread);
/**
* Wake up all threads waiting on this object that can be awoken, in priority order,

84
src/core/hle/kernel/mutex.cpp
View file

@ -6,26 +6,18 @@
#include <vector>
#include <boost/range/algorithm_ext/erase.hpp>
#include "common/assert.h"
#include "core/core.h"
#include "core/hle/kernel/kernel.h"
#include "core/hle/kernel/mutex.h"
#include "core/hle/kernel/thread.h"
namespace Kernel {
/**
* Resumes a thread waiting for the specified mutex
* @param mutex The mutex that some thread is waiting on
*/
static void ResumeWaitingThread(Mutex* mutex) {
// Reset mutex lock thread handle, nothing is waiting
mutex->lock_count = 0;
mutex->holding_thread = nullptr;
mutex->WakeupAllWaitingThreads();
}
void ReleaseThreadMutexes(Thread* thread) {
for (auto& mtx : thread->held_mutexes) {
ResumeWaitingThread(mtx.get());
mtx->lock_count = 0;
mtx->holding_thread = nullptr;
mtx->WakeupAllWaitingThreads();
}
thread->held_mutexes.clear();
}
@ -40,52 +32,74 @@ SharedPtr<Mutex> Mutex::Create(bool initial_locked, std::string name) {
mutex->name = std::move(name);
mutex->holding_thread = nullptr;
// Acquire mutex with current thread if initialized as locked...
// Acquire mutex with current thread if initialized as locked
if (initial_locked)
mutex->Acquire();
mutex->Acquire(GetCurrentThread());
return mutex;
}
bool Mutex::ShouldWait() {
auto thread = GetCurrentThread();
bool wait = lock_count > 0 && holding_thread != thread;
// If the holding thread of the mutex is lower priority than this thread, that thread should
// temporarily inherit this thread's priority
if (wait && thread->current_priority < holding_thread->current_priority)
holding_thread->BoostPriority(thread->current_priority);
return wait;
bool Mutex::ShouldWait(Thread* thread) const {
return lock_count > 0 && thread != holding_thread;
}
void Mutex::Acquire() {
Acquire(GetCurrentThread());
}
void Mutex::Acquire(Thread* thread) {
ASSERT_MSG(!ShouldWait(thread), "object unavailable!");
void Mutex::Acquire(SharedPtr<Thread> thread) {
ASSERT_MSG(!ShouldWait(), "object unavailable!");
// Actually "acquire" the mutex only if we don't already have it...
// Actually "acquire" the mutex only if we don't already have it
if (lock_count == 0) {
priority = thread->current_priority;
thread->held_mutexes.insert(this);
holding_thread = std::move(thread);
holding_thread = thread;
thread->UpdatePriority();
Core::System::GetInstance().PrepareReschedule();
}
lock_count++;
}
void Mutex::Release() {
// Only release if the mutex is held...
// Only release if the mutex is held
if (lock_count > 0) {
lock_count--;
// Yield to the next thread only if we've fully released the mutex...
// Yield to the next thread only if we've fully released the mutex
if (lock_count == 0) {
holding_thread->held_mutexes.erase(this);
ResumeWaitingThread(this);
holding_thread->UpdatePriority();
holding_thread = nullptr;
WakeupAllWaitingThreads();
Core::System::GetInstance().PrepareReschedule();
}
}
}
void Mutex::AddWaitingThread(SharedPtr<Thread> thread) {
WaitObject::AddWaitingThread(thread);
thread->pending_mutexes.insert(this);
UpdatePriority();
}
void Mutex::RemoveWaitingThread(Thread* thread) {
WaitObject::RemoveWaitingThread(thread);
thread->pending_mutexes.erase(this);
UpdatePriority();
}
void Mutex::UpdatePriority() {
if (!holding_thread)
return;
s32 best_priority = THREADPRIO_LOWEST;
for (auto& waiter : GetWaitingThreads()) {
if (waiter->current_priority < best_priority)
best_priority = waiter->current_priority;
}
if (best_priority != priority) {
priority = best_priority;
holding_thread->UpdatePriority();
}
}
} // namespace

17
src/core/hle/kernel/mutex.h
View file

@ -35,17 +35,22 @@ public:
}
int lock_count; ///< Number of times the mutex has been acquired
u32 priority; ///< The priority of the mutex, used for priority inheritance.
std::string name; ///< Name of mutex (optional)
SharedPtr<Thread> holding_thread; ///< Thread that has acquired the mutex
bool ShouldWait() override;
void Acquire() override;
/**
* Acquires the specified mutex for the specified thread
* @param thread Thread that will acquire the mutex
* Elevate the mutex priority to the best priority
* among the priorities of all its waiting threads.
*/
void Acquire(SharedPtr<Thread> thread);
void UpdatePriority();
bool ShouldWait(Thread* thread) const override;
void Acquire(Thread* thread) override;
void AddWaitingThread(SharedPtr<Thread> thread) override;
void RemoveWaitingThread(Thread* thread) override;
void Release();
private:

6
src/core/hle/kernel/semaphore.cpp
View file

@ -30,12 +30,12 @@ ResultVal<SharedPtr<Semaphore>> Semaphore::Create(s32 initial_count, s32 max_cou
return MakeResult<SharedPtr<Semaphore>>(std::move(semaphore));
}
bool Semaphore::ShouldWait() {
bool Semaphore::ShouldWait(Thread* thread) const {
return available_count <= 0;
}
void Semaphore::Acquire() {
ASSERT_MSG(!ShouldWait(), "object unavailable!");
void Semaphore::Acquire(Thread* thread) {
ASSERT_MSG(!ShouldWait(thread), "object unavailable!");
--available_count;
}

4
src/core/hle/kernel/semaphore.h
View file

@ -39,8 +39,8 @@ public:
s32 available_count; ///< Number of free slots left in the semaphore
std::string name; ///< Name of semaphore (optional)
bool ShouldWait() override;
void Acquire() override;
bool ShouldWait(Thread* thread) const override;
void Acquire(Thread* thread) override;
/**
* Releases a certain number of slots from a semaphore.

6
src/core/hle/kernel/server_port.cpp
View file

@ -14,13 +14,13 @@ namespace Kernel {
ServerPort::ServerPort() {}
ServerPort::~ServerPort() {}
bool ServerPort::ShouldWait() {
bool ServerPort::ShouldWait(Thread* thread) const {
// If there are no pending sessions, we wait until a new one is added.
return pending_sessions.size() == 0;
}
void ServerPort::Acquire() {
ASSERT_MSG(!ShouldWait(), "object unavailable!");
void ServerPort::Acquire(Thread* thread) {
ASSERT_MSG(!ShouldWait(thread), "object unavailable!");
}
std::tuple<SharedPtr<ServerPort>, SharedPtr<ClientPort>> ServerPort::CreatePortPair(

4
src/core/hle/kernel/server_port.h
View file

@ -53,8 +53,8 @@ public:
/// ServerSessions created from this port inherit a reference to this handler.
std::shared_ptr<Service::SessionRequestHandler> hle_handler;
bool ShouldWait() override;
void Acquire() override;
bool ShouldWait(Thread* thread) const override;
void Acquire(Thread* thread) override;
private:
ServerPort();

6
src/core/hle/kernel/server_session.cpp
View file

@ -29,12 +29,12 @@ ResultVal<SharedPtr<ServerSession>> ServerSession::Create(
return MakeResult<SharedPtr<ServerSession>>(std::move(server_session));
}
bool ServerSession::ShouldWait() {
bool ServerSession::ShouldWait(Thread* thread) const {
return !signaled;
}
void ServerSession::Acquire() {
ASSERT_MSG(!ShouldWait(), "object unavailable!");
void ServerSession::Acquire(Thread* thread) {
ASSERT_MSG(!ShouldWait(thread), "object unavailable!");
signaled = false;
}

4
src/core/hle/kernel/server_session.h
View file

@ -57,9 +57,9 @@ public:
*/
ResultCode HandleSyncRequest();
bool ShouldWait() override;
bool ShouldWait(Thread* thread) const override;
void Acquire() override;
void Acquire(Thread* thread) override;
std::string name; ///< The name of this session (optional)
bool signaled; ///< Whether there's new data available to this ServerSession

50
src/core/hle/kernel/thread.cpp
View file

@ -27,12 +27,12 @@ namespace Kernel {
/// Event type for the thread wake up event
static int ThreadWakeupEventType;
bool Thread::ShouldWait() {
bool Thread::ShouldWait(Thread* thread) const {
return status != THREADSTATUS_DEAD;
}
void Thread::Acquire() {
ASSERT_MSG(!ShouldWait(), "object unavailable!");
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
@ -72,7 +72,8 @@ Thread* GetCurrentThread() {
* @return True if the thread is waiting, false otherwise
*/
static bool CheckWait_WaitObject(const Thread* thread, WaitObject* wait_object) {
if (thread->status != THREADSTATUS_WAIT_SYNCH)
if (thread->status != THREADSTATUS_WAIT_SYNCH_ALL &&
thread->status != THREADSTATUS_WAIT_SYNCH_ANY)
return false;
auto itr = std::find(thread->wait_objects.begin(), thread->wait_objects.end(), wait_object);
@ -90,9 +91,6 @@ static bool CheckWait_AddressArbiter(const Thread* thread, VAddr wait_address) {
}
void Thread::Stop() {
// Release all the mutexes that this thread holds
ReleaseThreadMutexes(this);
// Cancel any outstanding wakeup events for this thread
CoreTiming::UnscheduleEvent(ThreadWakeupEventType, callback_handle);
wakeup_callback_handle_table.Close(callback_handle);
@ -114,6 +112,9 @@ void Thread::Stop() {
}
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 =
@ -199,8 +200,8 @@ static void SwitchContext(Thread* new_thread) {
// Load context of new thread
if (new_thread) {
DEBUG_ASSERT_MSG(new_thread->status == THREADSTATUS_READY,
"Thread must be ready to become running.");
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);
@ -253,7 +254,7 @@ void WaitCurrentThread_WaitSynchronization(std::vector<SharedPtr<WaitObject>> wa
Thread* thread = GetCurrentThread();
thread->wait_set_output = wait_set_output;
thread->wait_objects = std::move(wait_objects);
thread->status = THREADSTATUS_WAIT_SYNCH;
thread->status = THREADSTATUS_WAIT_SYNCH_ANY;
}
void WaitCurrentThread_ArbitrateAddress(VAddr wait_address) {
@ -281,7 +282,8 @@ static void ThreadWakeupCallback(u64 thread_handle, int cycles_late) {
return;
}
if (thread->status == THREADSTATUS_WAIT_SYNCH || thread->status == THREADSTATUS_WAIT_ARB) {
if (thread->status == THREADSTATUS_WAIT_SYNCH_ANY ||
thread->status == THREADSTATUS_WAIT_SYNCH_ALL || thread->status == THREADSTATUS_WAIT_ARB) {
thread->wait_set_output = false;
// Remove the thread from each of its waiting objects' waitlists
for (auto& object : thread->wait_objects)
@ -305,8 +307,11 @@ void Thread::WakeAfterDelay(s64 nanoseconds) {
}
void Thread::ResumeFromWait() {
ASSERT_MSG(wait_objects.empty(), "Thread is waking up while waiting for objects");
switch (status) {
case THREADSTATUS_WAIT_SYNCH:
case THREADSTATUS_WAIT_SYNCH_ALL:
case THREADSTATUS_WAIT_SYNCH_ANY:
case THREADSTATUS_WAIT_ARB:
case THREADSTATUS_WAIT_SLEEP:
break;
@ -515,8 +520,21 @@ void Thread::SetPriority(s32 priority) {
nominal_priority = current_priority = priority;
}
void Thread::UpdatePriority() {
s32 best_priority = nominal_priority;
for (auto& mutex : held_mutexes) {
if (mutex->priority < best_priority)
best_priority = mutex->priority;
}
BoostPriority(best_priority);
}
void Thread::BoostPriority(s32 priority) {
ready_queue.move(this, current_priority, 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;
}
@ -563,6 +581,12 @@ 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 std::distance(match, wait_objects.rend()) - 1;
}
////////////////////////////////////////////////////////////////////////////////////////////////////
void ThreadingInit() {

48
src/core/hle/kernel/thread.h
View file

@ -31,13 +31,14 @@ enum ThreadProcessorId : s32 {
};
enum ThreadStatus {
THREADSTATUS_RUNNING, ///< Currently running
THREADSTATUS_READY, ///< Ready to run
THREADSTATUS_WAIT_ARB, ///< Waiting on an address arbiter
THREADSTATUS_WAIT_SLEEP, ///< Waiting due to a SleepThread SVC
THREADSTATUS_WAIT_SYNCH, ///< Waiting due to a WaitSynchronization SVC
THREADSTATUS_DORMANT, ///< Created but not yet made ready
THREADSTATUS_DEAD ///< Run to completion, or forcefully terminated
THREADSTATUS_RUNNING, ///< Currently running
THREADSTATUS_READY, ///< Ready to run
THREADSTATUS_WAIT_ARB, ///< Waiting on an address arbiter
THREADSTATUS_WAIT_SLEEP, ///< Waiting due to a SleepThread SVC
THREADSTATUS_WAIT_SYNCH_ANY, ///< Waiting due to WaitSynch1 or WaitSynchN with wait_all = false
THREADSTATUS_WAIT_SYNCH_ALL, ///< Waiting due to WaitSynchronizationN with wait_all = true
THREADSTATUS_DORMANT, ///< Created but not yet made ready
THREADSTATUS_DEAD ///< Run to completion, or forcefully terminated
};
namespace Kernel {
@ -72,8 +73,8 @@ public:
return HANDLE_TYPE;
}
bool ShouldWait() override;
void Acquire() override;
bool ShouldWait(Thread* thread) const override;
void Acquire(Thread* thread) override;
/**
* Gets the thread's current priority
@ -89,6 +90,12 @@ public:
*/
void SetPriority(s32 priority);
/**
* Boost's a thread's priority to the best priority among the thread's held mutexes.
* This prevents priority inversion via priority inheritance.
*/
void UpdatePriority();
/**
* Temporarily boosts the thread's priority until the next time it is scheduled
* @param priority The new priority
@ -128,13 +135,14 @@ public:
/**
* Retrieves the index that this particular object occupies in the list of objects
* that the thread passed to WaitSynchronizationN.
* that the thread passed to WaitSynchronizationN, starting the search from the last element.
* It is used to set the output value of WaitSynchronizationN when the thread is awakened.
* When a thread wakes up due to an object signal, the kernel will use the index of the last
* matching object in the wait objects list in case of having multiple instances of the same
* object in the list.
* @param object Object to query the index of.
*/
s32 GetWaitObjectIndex(const WaitObject* object) const {
return wait_objects_index.at(object->GetObjectId());
}
s32 GetWaitObjectIndex(WaitObject* object) const;
/**
* Stops a thread, invalidating it from further use
@ -152,10 +160,10 @@ public:
/**
* Returns whether this thread is waiting for all the objects in
* its wait list to become ready, as a result of a WaitSynchronizationN call
* with wait_all = true, or a ReplyAndReceive call.
* with wait_all = true.
*/
bool IsSleepingOnWaitAll() const {
return !wait_objects.empty();
return status == THREADSTATUS_WAIT_SYNCH_ALL;
}
ARM_Interface::ThreadContext context;
@ -178,15 +186,15 @@ public:
/// Mutexes currently held by this thread, which will be released when it exits.
boost::container::flat_set<SharedPtr<Mutex>> held_mutexes;
/// Mutexes that this thread is currently waiting for.
boost::container::flat_set<SharedPtr<Mutex>> pending_mutexes;
SharedPtr<Process> owner_process; ///< Process that owns this thread
/// Objects that the thread is waiting on.
/// This is only populated when the thread should wait for all the objects to become ready.
/// Objects that the thread is waiting on, in the same order as they were
// passed to WaitSynchronization1/N.
std::vector<SharedPtr<WaitObject>> wait_objects;
/// Mapping of Object ids to their position in the last waitlist that this object waited on.
boost::container::flat_map<int, s32> wait_objects_index;
VAddr wait_address; ///< If waiting on an AddressArbiter, this is the arbitration address
/// True if the WaitSynchronizationN output parameter should be set on thread wakeup.

6
src/core/hle/kernel/timer.cpp
View file

@ -39,12 +39,12 @@ SharedPtr<Timer> Timer::Create(ResetType reset_type, std::string name) {
return timer;
}
bool Timer::ShouldWait() {
bool Timer::ShouldWait(Thread* thread) const {
return !signaled;
}
void Timer::Acquire() {
ASSERT_MSG(!ShouldWait(), "object unavailable!");
void Timer::Acquire(Thread* thread) {
ASSERT_MSG(!ShouldWait(thread), "object unavailable!");
if (reset_type == ResetType::OneShot)
signaled = false;

4
src/core/hle/kernel/timer.h
View file

@ -39,8 +39,8 @@ public:
u64 initial_delay; ///< The delay until the timer fires for the first time
u64 interval_delay; ///< The delay until the timer fires after the first time
bool ShouldWait() override;
void Acquire() override;
bool ShouldWait(Thread* thread) const override;
void Acquire(Thread* thread) override;
/**
* Starts the timer, with the specified initial delay and interval.

69
src/core/hle/svc.cpp
View file

@ -248,6 +248,8 @@ static ResultCode SendSyncRequest(Kernel::Handle handle) {
LOG_TRACE(Kernel_SVC, "called handle=0x%08X(%s)", handle, session->GetName().c_str());
Core::System::GetInstance().PrepareReschedule();
// TODO(Subv): svcSendSyncRequest should put the caller thread to sleep while the server
// responds and cause a reschedule.
return session->SendSyncRequest();
@ -270,27 +272,27 @@ static ResultCode WaitSynchronization1(Kernel::Handle handle, s64 nano_seconds)
LOG_TRACE(Kernel_SVC, "called handle=0x%08X(%s:%s), nanoseconds=%lld", handle,
object->GetTypeName().c_str(), object->GetName().c_str(), nano_seconds);
if (object->ShouldWait()) {
if (object->ShouldWait(thread)) {
if (nano_seconds == 0)
return ERR_SYNC_TIMEOUT;
thread->wait_objects = {object};
object->AddWaitingThread(thread);
// TODO(Subv): Perform things like update the mutex lock owner's priority to
// prevent priority inversion. Currently this is done in Mutex::ShouldWait,
// but it should be moved to a function that is called from here.
thread->status = THREADSTATUS_WAIT_SYNCH;
thread->status = THREADSTATUS_WAIT_SYNCH_ANY;
// Create an event to wake the thread up after the specified nanosecond delay has passed
thread->WakeAfterDelay(nano_seconds);
Core::System::GetInstance().PrepareReschedule();
// Note: The output of this SVC will be set to RESULT_SUCCESS if the thread
// resumes due to a signal in its wait objects.
// Otherwise we retain the default value of timeout.
return ERR_SYNC_TIMEOUT;
}
object->Acquire();
object->Acquire(thread);
return RESULT_SUCCESS;
}
@ -324,19 +326,14 @@ static ResultCode WaitSynchronizationN(s32* out, Kernel::Handle* handles, s32 ha
objects[i] = object;
}
// Clear the mapping of wait object indices.
// We don't want any lingering state in this map.
// It will be repopulated later in the wait_all = false case.
thread->wait_objects_index.clear();
if (wait_all) {
bool all_available =
std::all_of(objects.begin(), objects.end(),
[](const ObjectPtr& object) { return !object->ShouldWait(); });
[thread](const ObjectPtr& object) { return !object->ShouldWait(thread); });
if (all_available) {
// We can acquire all objects right now, do so.
for (auto& object : objects)
object->Acquire();
object->Acquire(thread);
// Note: In this case, the `out` parameter is not set,
// and retains whatever value it had before.
return RESULT_SUCCESS;
@ -350,22 +347,20 @@ static ResultCode WaitSynchronizationN(s32* out, Kernel::Handle* handles, s32 ha
return ERR_SYNC_TIMEOUT;
// Put the thread to sleep
thread->status = THREADSTATUS_WAIT_SYNCH;
thread->status = THREADSTATUS_WAIT_SYNCH_ALL;
// Add the thread to each of the objects' waiting threads.
for (auto& object : objects) {
object->AddWaitingThread(thread);
// TODO(Subv): Perform things like update the mutex lock owner's priority to
// prevent priority inversion. Currently this is done in Mutex::ShouldWait,
// but it should be moved to a function that is called from here.
}
// Set the thread's waitlist to the list of objects passed to WaitSynchronizationN
thread->wait_objects = std::move(objects);
// Create an event to wake the thread up after the specified nanosecond delay has passed
thread->WakeAfterDelay(nano_seconds);
Core::System::GetInstance().PrepareReschedule();
// This value gets set to -1 by default in this case, it is not modified after this.
*out = -1;
// Note: The output of this SVC will be set to RESULT_SUCCESS if the thread resumes due to
@ -373,13 +368,14 @@ static ResultCode WaitSynchronizationN(s32* out, Kernel::Handle* handles, s32 ha
return ERR_SYNC_TIMEOUT;
} else {
// Find the first object that is acquirable in the provided list of objects
auto itr = std::find_if(objects.begin(), objects.end(),
[](const ObjectPtr& object) { return !object->ShouldWait(); });
auto itr = std::find_if(objects.begin(), objects.end(), [thread](const ObjectPtr& object) {
return !object->ShouldWait(thread);
});
if (itr != objects.end()) {
// We found a ready object, acquire it and set the result value
Kernel::WaitObject* object = itr->get();
object->Acquire();
object->Acquire(thread);
*out = std::distance(objects.begin(), itr);
return RESULT_SUCCESS;
}
@ -392,28 +388,24 @@ static ResultCode WaitSynchronizationN(s32* out, Kernel::Handle* handles, s32 ha
return ERR_SYNC_TIMEOUT;
// Put the thread to sleep
thread->status = THREADSTATUS_WAIT_SYNCH;
// Clear the thread's waitlist, we won't use it for wait_all = false
thread->wait_objects.clear();
thread->status = THREADSTATUS_WAIT_SYNCH_ANY;
// Add the thread to each of the objects' waiting threads.
for (size_t i = 0; i < objects.size(); ++i) {
Kernel::WaitObject* object = objects[i].get();
// Set the index of this object in the mapping of Objects -> index for this thread.
thread->wait_objects_index[object->GetObjectId()] = static_cast<int>(i);
object->AddWaitingThread(thread);
// TODO(Subv): Perform things like update the mutex lock owner's priority to
// prevent priority inversion. Currently this is done in Mutex::ShouldWait,
// but it should be moved to a function that is called from here.
}
thread->wait_objects = std::move(objects);
// Note: If no handles and no timeout were given, then the thread will deadlock, this is
// consistent with hardware behavior.
// Create an event to wake the thread up after the specified nanosecond delay has passed
thread->WakeAfterDelay(nano_seconds);
Core::System::GetInstance().PrepareReschedule();
// Note: The output of this SVC will be set to RESULT_SUCCESS if the thread resumes due to a
// signal in one of its wait objects.
// Otherwise we retain the default value of timeout, and -1 in the out parameter
@ -448,6 +440,9 @@ static ResultCode ArbitrateAddress(Kernel::Handle handle, u32 address, u32 type,
auto res = arbiter->ArbitrateAddress(static_cast<Kernel::ArbitrationType>(type), address, value,
nanoseconds);
// TODO(Subv): Identify in which specific cases this call should cause a reschedule.
Core::System::GetInstance().PrepareReschedule();
return res;
}
@ -574,6 +569,8 @@ static ResultCode CreateThread(Kernel::Handle* out_handle, s32 priority, u32 ent
CASCADE_RESULT(*out_handle, Kernel::g_handle_table.Create(std::move(thread)));
Core::System::GetInstance().PrepareReschedule();
LOG_TRACE(Kernel_SVC, "called entrypoint=0x%08X (%s), arg=0x%08X, stacktop=0x%08X, "
"threadpriority=0x%08X, processorid=0x%08X : created handle=0x%08X",
entry_point, name.c_str(), arg, stack_top, priority, processor_id, *out_handle);
@ -586,6 +583,7 @@ static void ExitThread() {
LOG_TRACE(Kernel_SVC, "called, pc=0x%08X", Core::CPU().GetPC());
Kernel::ExitCurrentThread();
Core::System::GetInstance().PrepareReschedule();
}
/// Gets the priority for the specified thread
@ -605,6 +603,13 @@ static ResultCode SetThreadPriority(Kernel::Handle handle, s32 priority) {
return ERR_INVALID_HANDLE;
thread->SetPriority(priority);
thread->UpdatePriority();
// Update the mutexes that this thread is waiting for
for (auto& mutex : thread->pending_mutexes)
mutex->UpdatePriority();
Core::System::GetInstance().PrepareReschedule();
return RESULT_SUCCESS;
}
@ -849,6 +854,8 @@ static void SleepThread(s64 nanoseconds) {
// Create an event to wake the thread up after the specified nanosecond delay has passed
Kernel::GetCurrentThread()->WakeAfterDelay(nanoseconds);
Core::System::GetInstance().PrepareReschedule();
}
/// This returns the total CPU ticks elapsed since the CPU was powered-on
@ -1184,8 +1191,6 @@ void CallSVC(u32 immediate) {
if (info) {
if (info->func) {
info->func();
// TODO(Subv): Not all service functions should cause a reschedule in all cases.
Core::System::GetInstance().PrepareReschedule();
} else {
LOG_ERROR(Kernel_SVC, "unimplemented SVC function %s(..)", info->name);
}