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-rw-r--r--src/core/hle/kernel/mutex.cpp170
1 files changed, 0 insertions, 170 deletions
diff --git a/src/core/hle/kernel/mutex.cpp b/src/core/hle/kernel/mutex.cpp
deleted file mode 100644
index 8a0faacf8..000000000
--- a/src/core/hle/kernel/mutex.cpp
+++ /dev/null
@@ -1,170 +0,0 @@
-// Copyright 2014 Citra Emulator Project
-// Licensed under GPLv2 or any later version
-// Refer to the license.txt file included.
-
-#include <memory>
-#include <utility>
-#include <vector>
-
-#include "common/assert.h"
-#include "common/logging/log.h"
-#include "core/core.h"
-#include "core/hle/kernel/errors.h"
-#include "core/hle/kernel/handle_table.h"
-#include "core/hle/kernel/k_scheduler.h"
-#include "core/hle/kernel/kernel.h"
-#include "core/hle/kernel/mutex.h"
-#include "core/hle/kernel/object.h"
-#include "core/hle/kernel/process.h"
-#include "core/hle/kernel/thread.h"
-#include "core/hle/result.h"
-#include "core/memory.h"
-
-namespace Kernel {
-
-/// Returns the number of threads that are waiting for a mutex, and the highest priority one among
-/// those.
-static std::pair<std::shared_ptr<Thread>, u32> GetHighestPriorityMutexWaitingThread(
- const std::shared_ptr<Thread>& current_thread, VAddr mutex_addr) {
-
- std::shared_ptr<Thread> highest_priority_thread;
- u32 num_waiters = 0;
-
- for (const auto& thread : current_thread->GetMutexWaitingThreads()) {
- if (thread->GetMutexWaitAddress() != mutex_addr)
- continue;
-
- ++num_waiters;
- if (highest_priority_thread == nullptr ||
- thread->GetPriority() < highest_priority_thread->GetPriority()) {
- highest_priority_thread = thread;
- }
- }
-
- return {highest_priority_thread, num_waiters};
-}
-
-/// 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)
- continue;
-
- ASSERT(thread->GetLockOwner() == current_thread.get());
- current_thread->RemoveMutexWaiter(thread);
- if (new_owner != thread)
- new_owner->AddMutexWaiter(thread);
- }
-}
-
-Mutex::Mutex(Core::System& system) : system{system} {}
-Mutex::~Mutex() = default;
-
-ResultCode Mutex::TryAcquire(VAddr address, Handle holding_thread_handle,
- Handle requesting_thread_handle) {
- // 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;
- }
-
- auto& kernel = system.Kernel();
- std::shared_ptr<Thread> current_thread =
- SharedFrom(kernel.CurrentScheduler()->GetCurrentThread());
- {
- KScopedSchedulerLock lock(kernel);
- // The mutex address must be 4-byte aligned
- if ((address % sizeof(u32)) != 0) {
- return ERR_INVALID_ADDRESS;
- }
-
- 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);
-
- // TODO(Subv): It is currently unknown if it is possible to lock a mutex in behalf of
- // another thread.
- ASSERT(requesting_thread == current_thread);
-
- current_thread->SetSynchronizationResults(nullptr, RESULT_SUCCESS);
-
- 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;
- }
-
- if (holding_thread == nullptr) {
- return ERR_INVALID_HANDLE;
- }
-
- // Wait until the mutex is released
- current_thread->SetMutexWaitAddress(address);
- current_thread->SetWaitHandle(requesting_thread_handle);
-
- current_thread->SetState(ThreadState::Waiting);
-
- // Update the lock holder thread's priority to prevent priority inversion.
- holding_thread->AddMutexWaiter(current_thread);
- }
-
- {
- KScopedSchedulerLock lock(kernel);
- auto* owner = current_thread->GetLockOwner();
- if (owner != nullptr) {
- owner->RemoveMutexWaiter(current_thread);
- }
- }
- return current_thread->GetSignalingResult();
-}
-
-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, nullptr};
- }
-
- auto [new_owner, num_waiters] = GetHighestPriorityMutexWaitingThread(owner, address);
- if (new_owner == nullptr) {
- system.Memory().Write32(address, 0);
- return {RESULT_SUCCESS, nullptr};
- }
- // Transfer the ownership of the mutex from the previous owner to the new one.
- 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->Wakeup();
-
- system.Memory().Write32(address, mutex_value);
- return {RESULT_SUCCESS, new_owner};
-}
-
-ResultCode Mutex::Release(VAddr address) {
- auto& kernel = system.Kernel();
- KScopedSchedulerLock lock(kernel);
-
- std::shared_ptr<Thread> current_thread =
- SharedFrom(kernel.CurrentScheduler()->GetCurrentThread());
-
- auto [result, new_owner] = Unlock(current_thread, address);
-
- if (result != RESULT_SUCCESS && new_owner != nullptr) {
- new_owner->SetSynchronizationResults(nullptr, result);
- }
-
- return result;
-}
-
-} // namespace Kernel