From 5224cc49c4daa8d20999bad15a9b16d8d16b9d10 Mon Sep 17 00:00:00 2001 From: Subv Date: Sun, 12 Aug 2018 16:35:27 -0500 Subject: Kernel/Mutex: Don't duplicate threads in the mutex waiter list. Exit from AddMutexWaiter early if the thread is already waiting for a mutex owned by the owner thread. This accounts for the possibility of a thread that is waiting on a condition variable being awakened twice in a row. Also added more validation asserts. This should fix one of the random crashes in Breath Of The Wild. --- src/core/hle/kernel/svc.cpp | 3 +-- src/core/hle/kernel/thread.cpp | 21 +++++++++++++++++++++ 2 files changed, 22 insertions(+), 2 deletions(-) diff --git a/src/core/hle/kernel/svc.cpp b/src/core/hle/kernel/svc.cpp index 5db2db687..5818cc06d 100644 --- a/src/core/hle/kernel/svc.cpp +++ b/src/core/hle/kernel/svc.cpp @@ -706,8 +706,7 @@ static ResultCode SignalProcessWideKey(VAddr condition_variable_addr, s32 target Handle owner_handle = static_cast(mutex_val & Mutex::MutexOwnerMask); auto owner = g_handle_table.Get(owner_handle); ASSERT(owner); - ASSERT(thread->status != ThreadStatus::Running); - thread->status = ThreadStatus::WaitMutex; + ASSERT(thread->status == ThreadStatus::WaitMutex); thread->wakeup_callback = nullptr; owner->AddMutexWaiter(thread); diff --git a/src/core/hle/kernel/thread.cpp b/src/core/hle/kernel/thread.cpp index b9022feae..40918ca81 100644 --- a/src/core/hle/kernel/thread.cpp +++ b/src/core/hle/kernel/thread.cpp @@ -419,12 +419,33 @@ VAddr Thread::GetCommandBufferAddress() const { } void Thread::AddMutexWaiter(SharedPtr thread) { + if (thread->lock_owner == this) { + // If the thread is already waiting for this thread to release the mutex, ensure that the + // waiters list is consistent and return without doing anything. + auto itr = std::find(wait_mutex_threads.begin(), wait_mutex_threads.end(), thread); + ASSERT(itr != wait_mutex_threads.end()); + return; + } + + // A thread can't wait on two different mutexes at the same time. + ASSERT(thread->lock_owner == nullptr); + + // Ensure that the thread is not already in the list of mutex waiters + auto itr = std::find(wait_mutex_threads.begin(), wait_mutex_threads.end(), thread); + ASSERT(itr == wait_mutex_threads.end()); + thread->lock_owner = this; wait_mutex_threads.emplace_back(std::move(thread)); UpdatePriority(); } void Thread::RemoveMutexWaiter(SharedPtr thread) { + ASSERT(thread->lock_owner == this); + + // Ensure that the thread is in the list of mutex waiters + auto itr = std::find(wait_mutex_threads.begin(), wait_mutex_threads.end(), thread); + ASSERT(itr != wait_mutex_threads.end()); + boost::remove_erase(wait_mutex_threads, thread); thread->lock_owner = nullptr; UpdatePriority(); -- cgit v1.2.3