diff --git a/src/citra_qt/debugger/wait_tree.cpp b/src/citra_qt/debugger/wait_tree.cpp
index 8c244b6b2c47234ebe522bcb593eb8f72652febe..ebcc02894cde5e773759c0c525727f07bfc6c2ad 100644
--- a/src/citra_qt/debugger/wait_tree.cpp
+++ b/src/citra_qt/debugger/wait_tree.cpp
@@ -257,10 +257,9 @@ std::vector<std::unique_ptr<WaitTreeItem>> WaitTreeMutex::GetChildren() const {
std::vector<std::unique_ptr<WaitTreeItem>> list(WaitTreeWaitObject::GetChildren());
const auto& mutex = static_cast<const Kernel::Mutex&>(object);
- if (mutex.lock_count) {
- list.push_back(
- std::make_unique<WaitTreeText>(tr("locked %1 times by thread:").arg(mutex.lock_count)));
- list.push_back(std::make_unique<WaitTreeThread>(*mutex.holding_thread));
+ if (mutex.GetHasWaiters()) {
+ list.push_back(std::make_unique<WaitTreeText>(tr("locked by thread:")));
+ list.push_back(std::make_unique<WaitTreeThread>(*mutex.GetHoldingThread()));
} else {
list.push_back(std::make_unique<WaitTreeText>(tr("free")));
}
diff --git a/src/core/hle/kernel/mutex.cpp b/src/core/hle/kernel/mutex.cpp
index 1b7cda7403ead06f69feada6d21168445edabe83..0ee92a3e3a0fd4339aa6a5aae0cb0b2381743125 100644
--- a/src/core/hle/kernel/mutex.cpp
+++ b/src/core/hle/kernel/mutex.cpp
@@ -17,8 +17,8 @@ namespace Kernel {
void ReleaseThreadMutexes(Thread* thread) {
for (auto& mtx : thread->held_mutexes) {
- mtx->lock_count = 0;
- mtx->holding_thread = nullptr;
+ mtx->SetHasWaiters(false);
+ mtx->SetHoldingThread(nullptr);
mtx->WakeupAllWaitingThreads();
}
thread->held_mutexes.clear();
@@ -31,10 +31,8 @@ SharedPtr<Mutex> Mutex::Create(SharedPtr<Kernel::Thread> holding_thread, VAddr g
std::string name) {
SharedPtr<Mutex> mutex(new Mutex);
- mutex->lock_count = 0;
mutex->guest_addr = guest_addr;
mutex->name = std::move(name);
- mutex->holding_thread = nullptr;
// If mutex was initialized with a holding thread, acquire it by the holding thread
if (holding_thread) {
@@ -51,56 +49,32 @@ SharedPtr<Mutex> Mutex::Create(SharedPtr<Kernel::Thread> holding_thread, VAddr g
}
bool Mutex::ShouldWait(Thread* thread) const {
- return lock_count > 0 && thread != holding_thread;
+ auto holding_thread = GetHoldingThread();
+ return holding_thread != nullptr && thread != holding_thread;
}
void Mutex::Acquire(Thread* thread) {
ASSERT_MSG(!ShouldWait(thread), "object unavailable!");
- // 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 = thread;
- thread->UpdatePriority();
- UpdateGuestState();
- Core::System::GetInstance().PrepareReschedule();
- }
-
- lock_count++;
+ priority = thread->current_priority;
+ thread->held_mutexes.insert(this);
+ SetHoldingThread(thread);
+ thread->UpdatePriority();
+ Core::System::GetInstance().PrepareReschedule();
}
ResultCode Mutex::Release(Thread* thread) {
- // We can only release the mutex if it's held by the calling thread.
- if (thread != holding_thread) {
- if (holding_thread) {
- LOG_ERROR(
- Kernel,
- "Tried to release a mutex (owned by thread id %u) from a different thread id %u",
- holding_thread->thread_id, thread->thread_id);
- }
- // TODO(bunnei): Use correct error code
- return ResultCode(-1);
- }
+ auto holding_thread = GetHoldingThread();
+ ASSERT(holding_thread);
- // Note: It should not be possible for the situation where the mutex has a holding thread with a
- // zero lock count to occur. The real kernel still checks for this, so we do too.
- if (lock_count <= 0) {
- // TODO(bunnei): Use correct error code
- return ResultCode(-1);
- }
-
- lock_count--;
+ // We can only release the mutex if it's held by the calling thread.
+ ASSERT(thread == holding_thread);
- // Yield to the next thread only if we've fully released the mutex
- if (lock_count == 0) {
- holding_thread->held_mutexes.erase(this);
- holding_thread->UpdatePriority();
- holding_thread = nullptr;
- WakeupAllWaitingThreads();
- UpdateGuestState();
- Core::System::GetInstance().PrepareReschedule();
- }
+ holding_thread->held_mutexes.erase(this);
+ holding_thread->UpdatePriority();
+ SetHoldingThread(nullptr);
+ WakeupAllWaitingThreads();
+ Core::System::GetInstance().PrepareReschedule();
return RESULT_SUCCESS;
}
@@ -108,19 +82,20 @@ ResultCode Mutex::Release(Thread* thread) {
void Mutex::AddWaitingThread(SharedPtr<Thread> thread) {
WaitObject::AddWaitingThread(thread);
thread->pending_mutexes.insert(this);
+ SetHasWaiters(true);
UpdatePriority();
- UpdateGuestState();
}
void Mutex::RemoveWaitingThread(Thread* thread) {
WaitObject::RemoveWaitingThread(thread);
thread->pending_mutexes.erase(this);
+ if (!GetHasWaiters())
+ SetHasWaiters(!GetWaitingThreads().empty());
UpdatePriority();
- UpdateGuestState();
}
void Mutex::UpdatePriority() {
- if (!holding_thread)
+ if (!GetHoldingThread())
return;
u32 best_priority = THREADPRIO_LOWEST;
@@ -131,21 +106,35 @@ void Mutex::UpdatePriority() {
if (best_priority != priority) {
priority = best_priority;
- holding_thread->UpdatePriority();
+ GetHoldingThread()->UpdatePriority();
}
}
-void Mutex::UpdateGuestState() {
+Handle Mutex::GetOwnerHandle() const {
+ GuestState guest_state{Memory::Read32(guest_addr)};
+ return guest_state.holding_thread_handle;
+}
+
+SharedPtr<Thread> Mutex::GetHoldingThread() const {
+ GuestState guest_state{Memory::Read32(guest_addr)};
+ return g_handle_table.Get<Thread>(guest_state.holding_thread_handle);
+}
+
+void Mutex::SetHoldingThread(SharedPtr<Thread> thread) {
GuestState guest_state{Memory::Read32(guest_addr)};
- guest_state.has_waiters.Assign(!GetWaitingThreads().empty());
- guest_state.holding_thread_handle.Assign(holding_thread ? holding_thread->guest_handle : 0);
+ guest_state.holding_thread_handle.Assign(thread ? thread->guest_handle : 0);
Memory::Write32(guest_addr, guest_state.raw);
}
-void Mutex::VerifyGuestState() {
+bool Mutex::GetHasWaiters() const {
GuestState guest_state{Memory::Read32(guest_addr)};
- ASSERT(guest_state.has_waiters == !GetWaitingThreads().empty());
- ASSERT(guest_state.holding_thread_handle == holding_thread->guest_handle);
+ return guest_state.has_waiters != 0;
+}
+
+void Mutex::SetHasWaiters(bool has_waiters) {
+ GuestState guest_state{Memory::Read32(guest_addr)};
+ guest_state.has_waiters.Assign(has_waiters ? 1 : 0);
+ Memory::Write32(guest_addr, guest_state.raw);
}
} // namespace Kernel
diff --git a/src/core/hle/kernel/mutex.h b/src/core/hle/kernel/mutex.h
index 87e3c15ee6482d59c632538479d3b89ed86c2fc2..49b6b454e696927c474a2bb4ee81dd13585b3514 100644
--- a/src/core/hle/kernel/mutex.h
+++ b/src/core/hle/kernel/mutex.h
@@ -41,10 +41,8 @@ public:
return HANDLE_TYPE;
}
- 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
VAddr guest_addr; ///< Address of the guest mutex value
/**
@@ -66,6 +64,19 @@ public:
*/
ResultCode Release(Thread* thread);
+ /// Gets the handle to the holding process stored in the guest state.
+ Handle GetOwnerHandle() const;
+
+ /// Gets the Thread pointed to by the owner handle
+ SharedPtr<Thread> GetHoldingThread() const;
+ /// Sets the holding process handle in the guest state.
+ void SetHoldingThread(SharedPtr<Thread> thread);
+
+ /// Returns the has_waiters bit in the guest state.
+ bool GetHasWaiters() const;
+ /// Sets the has_waiters bit in the guest state.
+ void SetHasWaiters(bool has_waiters);
+
private:
Mutex();
~Mutex() override;
@@ -79,12 +90,6 @@ private:
BitField<30, 1, u32_le> has_waiters;
};
static_assert(sizeof(GuestState) == 4, "GuestState size is incorrect");
-
- /// Updates the state of the object tracking this mutex in guest memory
- void UpdateGuestState();
-
- /// Verifies the state of the object tracking this mutex in guest memory
- void VerifyGuestState();
};
/**
diff --git a/src/core/hle/kernel/svc.cpp b/src/core/hle/kernel/svc.cpp
index 73793955a822fb60dde7cb136725f04f7fb43b28..a3ac3d7828d07480ce11ac9867a908f1344253ae 100644
--- a/src/core/hle/kernel/svc.cpp
+++ b/src/core/hle/kernel/svc.cpp
@@ -204,7 +204,6 @@ static ResultCode LockMutex(Handle holding_thread_handle, VAddr mutex_addr,
SharedPtr<Thread> holding_thread = g_handle_table.Get<Thread>(holding_thread_handle);
SharedPtr<Thread> requesting_thread = g_handle_table.Get<Thread>(requesting_thread_handle);
- ASSERT(holding_thread);
ASSERT(requesting_thread);
SharedPtr<Mutex> mutex = g_object_address_table.Get<Mutex>(mutex_addr);
@@ -214,6 +213,8 @@ static ResultCode LockMutex(Handle holding_thread_handle, VAddr mutex_addr,
mutex->name = Common::StringFromFormat("mutex-%llx", mutex_addr);
}
+ ASSERT(holding_thread == mutex->GetHoldingThread());
+
return WaitSynchronization1(mutex, requesting_thread.get());
}
@@ -491,6 +492,8 @@ static ResultCode WaitProcessWideKeyAtomic(VAddr mutex_addr, VAddr semaphore_add
mutex->name = Common::StringFromFormat("mutex-%llx", mutex_addr);
}
+ ASSERT(mutex->GetOwnerHandle() == thread_handle);
+
SharedPtr<Semaphore> semaphore = g_object_address_table.Get<Semaphore>(semaphore_addr);
if (!semaphore) {
// Create a new semaphore for the specified address if one does not already exist