diff options
Diffstat (limited to 'src/core/hle/kernel/mutex.cpp')
-rw-r--r-- | src/core/hle/kernel/mutex.cpp | 118 |
1 files changed, 66 insertions, 52 deletions
diff --git a/src/core/hle/kernel/mutex.cpp b/src/core/hle/kernel/mutex.cpp index 7869eb32b..8f6c944d1 100644 --- a/src/core/hle/kernel/mutex.cpp +++ b/src/core/hle/kernel/mutex.cpp @@ -34,8 +34,6 @@ static std::pair<std::shared_ptr<Thread>, u32> GetHighestPriorityMutexWaitingThr if (thread->GetMutexWaitAddress() != mutex_addr) continue; - ASSERT(thread->GetStatus() == ThreadStatus::WaitMutex); - ++num_waiters; if (highest_priority_thread == nullptr || thread->GetPriority() < highest_priority_thread->GetPriority()) { @@ -49,6 +47,7 @@ static std::pair<std::shared_ptr<Thread>, u32> GetHighestPriorityMutexWaitingThr /// Update the mutex owner field of all threads waiting on the mutex to point to the new owner. static void TransferMutexOwnership(VAddr mutex_addr, std::shared_ptr<Thread> current_thread, std::shared_ptr<Thread> new_owner) { + current_thread->RemoveMutexWaiter(new_owner); const auto threads = current_thread->GetMutexWaitingThreads(); for (const auto& thread : threads) { if (thread->GetMutexWaitAddress() != mutex_addr) @@ -72,85 +71,100 @@ ResultCode Mutex::TryAcquire(VAddr address, Handle holding_thread_handle, return ERR_INVALID_ADDRESS; } - const auto& handle_table = system.Kernel().CurrentProcess()->GetHandleTable(); + auto& kernel = system.Kernel(); std::shared_ptr<Thread> current_thread = - SharedFrom(system.CurrentScheduler().GetCurrentThread()); - std::shared_ptr<Thread> holding_thread = handle_table.Get<Thread>(holding_thread_handle); - std::shared_ptr<Thread> requesting_thread = handle_table.Get<Thread>(requesting_thread_handle); + SharedFrom(kernel.CurrentScheduler().GetCurrentThread()); + { + SchedulerLock lock(kernel); + // The mutex address must be 4-byte aligned + if ((address % sizeof(u32)) != 0) { + return ERR_INVALID_ADDRESS; + } - // TODO(Subv): It is currently unknown if it is possible to lock a mutex in behalf of another - // thread. - ASSERT(requesting_thread == current_thread); + const auto& handle_table = kernel.CurrentProcess()->GetHandleTable(); + std::shared_ptr<Thread> holding_thread = handle_table.Get<Thread>(holding_thread_handle); + std::shared_ptr<Thread> requesting_thread = + handle_table.Get<Thread>(requesting_thread_handle); - const u32 addr_value = system.Memory().Read32(address); + // TODO(Subv): It is currently unknown if it is possible to lock a mutex in behalf of + // another thread. + ASSERT(requesting_thread == current_thread); - // If the mutex isn't being held, just return success. - if (addr_value != (holding_thread_handle | Mutex::MutexHasWaitersFlag)) { - return RESULT_SUCCESS; - } + current_thread->SetSynchronizationResults(nullptr, RESULT_SUCCESS); - if (holding_thread == nullptr) { - LOG_ERROR(Kernel, "Holding thread does not exist! thread_handle={:08X}", - holding_thread_handle); - return ERR_INVALID_HANDLE; - } + const u32 addr_value = system.Memory().Read32(address); + + // If the mutex isn't being held, just return success. + if (addr_value != (holding_thread_handle | Mutex::MutexHasWaitersFlag)) { + return RESULT_SUCCESS; + } - // Wait until the mutex is released - current_thread->SetMutexWaitAddress(address); - current_thread->SetWaitHandle(requesting_thread_handle); + if (holding_thread == nullptr) { + return ERR_INVALID_HANDLE; + } - current_thread->SetStatus(ThreadStatus::WaitMutex); - current_thread->InvalidateWakeupCallback(); + // Wait until the mutex is released + current_thread->SetMutexWaitAddress(address); + current_thread->SetWaitHandle(requesting_thread_handle); - // Update the lock holder thread's priority to prevent priority inversion. - holding_thread->AddMutexWaiter(current_thread); + current_thread->SetStatus(ThreadStatus::WaitMutex); - system.PrepareReschedule(); + // Update the lock holder thread's priority to prevent priority inversion. + holding_thread->AddMutexWaiter(current_thread); + } - return RESULT_SUCCESS; + { + SchedulerLock lock(kernel); + auto* owner = current_thread->GetLockOwner(); + if (owner != nullptr) { + owner->RemoveMutexWaiter(current_thread); + } + } + return current_thread->GetSignalingResult(); } -ResultCode Mutex::Release(VAddr address) { +std::pair<ResultCode, std::shared_ptr<Thread>> Mutex::Unlock(std::shared_ptr<Thread> owner, + VAddr address) { // The mutex address must be 4-byte aligned if ((address % sizeof(u32)) != 0) { LOG_ERROR(Kernel, "Address is not 4-byte aligned! address={:016X}", address); - return ERR_INVALID_ADDRESS; + return {ERR_INVALID_ADDRESS, nullptr}; } - std::shared_ptr<Thread> current_thread = - SharedFrom(system.CurrentScheduler().GetCurrentThread()); - auto [thread, num_waiters] = GetHighestPriorityMutexWaitingThread(current_thread, address); - - // There are no more threads waiting for the mutex, release it completely. - if (thread == nullptr) { + auto [new_owner, num_waiters] = GetHighestPriorityMutexWaitingThread(owner, address); + if (new_owner == nullptr) { system.Memory().Write32(address, 0); - return RESULT_SUCCESS; + return {RESULT_SUCCESS, nullptr}; } - // Transfer the ownership of the mutex from the previous owner to the new one. - TransferMutexOwnership(address, current_thread, thread); - - u32 mutex_value = thread->GetWaitHandle(); - + TransferMutexOwnership(address, owner, new_owner); + u32 mutex_value = new_owner->GetWaitHandle(); if (num_waiters >= 2) { // Notify the guest that there are still some threads waiting for the mutex mutex_value |= Mutex::MutexHasWaitersFlag; } + new_owner->SetSynchronizationResults(nullptr, RESULT_SUCCESS); + new_owner->SetLockOwner(nullptr); + new_owner->ResumeFromWait(); - // Grant the mutex to the next waiting thread and resume it. system.Memory().Write32(address, mutex_value); + return {RESULT_SUCCESS, new_owner}; +} - ASSERT(thread->GetStatus() == ThreadStatus::WaitMutex); - thread->ResumeFromWait(); +ResultCode Mutex::Release(VAddr address) { + auto& kernel = system.Kernel(); + SchedulerLock lock(kernel); - thread->SetLockOwner(nullptr); - thread->SetCondVarWaitAddress(0); - thread->SetMutexWaitAddress(0); - thread->SetWaitHandle(0); - thread->SetWaitSynchronizationResult(RESULT_SUCCESS); + std::shared_ptr<Thread> current_thread = + SharedFrom(kernel.CurrentScheduler().GetCurrentThread()); - system.PrepareReschedule(); + auto [result, new_owner] = Unlock(current_thread, address); - return RESULT_SUCCESS; + if (result != RESULT_SUCCESS && new_owner != nullptr) { + new_owner->SetSynchronizationResults(nullptr, result); + } + + return result; } + } // namespace Kernel |