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Diffstat (limited to 'src/core/hle/kernel/mutex.cpp')
-rw-r--r--src/core/hle/kernel/mutex.cpp118
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