Kernel: Correct behavior of Condition Variables to be more similar to real hardware.

This commit ensures cond var threads act exactly as they do in the real console. The original implementation uses an RBTree and the behavior of cond var threads is that at the same priority level they act like a FIFO.
author: Fernando Sahmkow <fsahmkow27@gmail.com> 2019-11-14 20:13:18 -0400
committer: FernandoS27 <fsahmkow27@gmail.com> 2019-11-21 10:46:55 -0400
commit: 2d16507f9fa06e868349d6f57a78585aec8628fd (patch)
tree: 7931e2bb9db6d55e7be760f1a1dcff14de09db78 /src
parent: c52f37f259372485ac5902d9cae8de327c984a55 (diff)
5 files changed, 74 insertions, 15 deletions
diff --git a/src/core/hle/kernel/kernel.cpp b/src/core/hle/kernel/kernel.cpp
index f94ac150d0..cdf7944f78 100644
--- a/src/core/hle/kernel/kernel.cpp
+++ b/src/core/hle/kernel/kernel.cpp
@@ -66,6 +66,9 @@ static void ThreadWakeupCallback(u64 thread_handle, [[maybe_unused]] s64 cycles_
         thread->SetMutexWaitAddress(0);
         thread->SetCondVarWaitAddress(0);
         thread->SetWaitHandle(0);
+        if (thread->GetStatus() == ThreadStatus::WaitCondVar) {
+            thread->GetOwnerProcess()->RemoveConditionVariableThread(thread);
+        }
 
         auto* const lock_owner = thread->GetLockOwner();
         // Threads waking up by timeout from WaitProcessWideKey do not perform priority inheritance
diff --git a/src/core/hle/kernel/process.cpp b/src/core/hle/kernel/process.cpp
index 12a900bcc4..43576c6abc 100644
--- a/src/core/hle/kernel/process.cpp
+++ b/src/core/hle/kernel/process.cpp
@@ -142,6 +142,52 @@ u64 Process::GetTotalPhysicalMemoryUsedWithoutSystemResource() const {
     return GetTotalPhysicalMemoryUsed() - GetSystemResourceUsage();
 }
 
+void Process::InsertConditionVariableThread(SharedPtr<Thread> thread) {
+    auto it = cond_var_threads.begin();
+    while (it != cond_var_threads.end()) {
+        const SharedPtr<Thread> current_thread = *it;
+        if (current_thread->GetCondVarWaitAddress() < thread->GetCondVarWaitAddress()) {
+            if (current_thread->GetCondVarWaitAddress() == thread->GetCondVarWaitAddress()) {
+                if (current_thread->GetPriority() > thread->GetPriority()) {
+                    cond_var_threads.insert(it, thread);
+                    return;
+                }
+            } else {
+                cond_var_threads.insert(it, thread);
+                return;
+            }
+        }
+        ++it;
+    }
+    cond_var_threads.push_back(thread);
+}
+
+void Process::RemoveConditionVariableThread(SharedPtr<Thread> thread) {
+    auto it = cond_var_threads.begin();
+    while (it != cond_var_threads.end()) {
+        const SharedPtr<Thread> current_thread = *it;
+        if (current_thread.get() == thread.get()) {
+            cond_var_threads.erase(it);
+            return;
+        }
+        ++it;
+    }
+    UNREACHABLE();
+}
+
+std::vector<SharedPtr<Thread>> Process::GetConditionVariableThreads(const VAddr cond_var_addr) {
+    std::vector<SharedPtr<Thread>> result{};
+    auto it = cond_var_threads.begin();
+    while (it != cond_var_threads.end()) {
+        SharedPtr<Thread> current_thread = *it;
+        if (current_thread->GetCondVarWaitAddress() == cond_var_addr) {
+            result.push_back(current_thread);
+        }
+        ++it;
+    }
+    return result;
+}
+
 void Process::RegisterThread(const Thread* thread) {
     thread_list.push_back(thread);
 }
diff --git a/src/core/hle/kernel/process.h b/src/core/hle/kernel/process.h
index c2df451f3d..e8bff709bb 100644
--- a/src/core/hle/kernel/process.h
+++ b/src/core/hle/kernel/process.h
@@ -232,6 +232,15 @@ public:
         return thread_list;
     }
 
+    /// Insert a thread into the condition variable wait container
+    void InsertConditionVariableThread(SharedPtr<Thread> thread);
+
+    /// Remove a thread from the condition variable wait container
+    void RemoveConditionVariableThread(SharedPtr<Thread> thread);
+
+    /// Obtain all condition variable threads waiting for some address
+    std::vector<SharedPtr<Thread>> GetConditionVariableThreads(VAddr cond_var_addr);
+
     /// Registers a thread as being created under this process,
     /// adding it to this process' thread list.
     void RegisterThread(const Thread* thread);
@@ -375,6 +384,9 @@ private:
     /// List of threads that are running with this process as their owner.
     std::list<const Thread*> thread_list;
 
+    /// List of threads waiting for a condition variable
+    std::list<SharedPtr<Thread>> cond_var_threads;
+
     /// System context
     Core::System& system;
 
diff --git a/src/core/hle/kernel/svc.cpp b/src/core/hle/kernel/svc.cpp
index c63a9ba8bb..c27529f4d9 100644
--- a/src/core/hle/kernel/svc.cpp
+++ b/src/core/hle/kernel/svc.cpp
@@ -1626,6 +1626,7 @@ static ResultCode WaitProcessWideKeyAtomic(Core::System& system, VAddr mutex_add
     current_thread->SetWaitHandle(thread_handle);
     current_thread->SetStatus(ThreadStatus::WaitCondVar);
     current_thread->InvalidateWakeupCallback();
+    current_process->InsertConditionVariableThread(current_thread);
 
     current_thread->WakeAfterDelay(nano_seconds);
 
@@ -1644,21 +1645,9 @@ static ResultCode SignalProcessWideKey(Core::System& system, VAddr condition_var
     ASSERT(condition_variable_addr == Common::AlignDown(condition_variable_addr, 4));
 
     // Retrieve a list of all threads that are waiting for this condition variable.
-    std::vector<SharedPtr<Thread>> waiting_threads;
-    const auto& scheduler = system.GlobalScheduler();
-    const auto& thread_list = scheduler.GetThreadList();
-
-    for (const auto& thread : thread_list) {
-        if (thread->GetCondVarWaitAddress() == condition_variable_addr) {
-            waiting_threads.push_back(thread);
-        }
-    }
-
-    // Sort them by priority, such that the highest priority ones come first.
-    std::sort(waiting_threads.begin(), waiting_threads.end(),
-              [](const SharedPtr<Thread>& lhs, const SharedPtr<Thread>& rhs) {
-                  return lhs->GetPriority() < rhs->GetPriority();
-              });
+    auto* const current_process = system.Kernel().CurrentProcess();
+    std::vector<SharedPtr<Thread>> waiting_threads =
+        current_process->GetConditionVariableThreads(condition_variable_addr);
 
     // Only process up to 'target' threads, unless 'target' is -1, in which case process
     // them all.
@@ -1677,6 +1666,7 @@ static ResultCode SignalProcessWideKey(Core::System& system, VAddr condition_var
 
         // liberate Cond Var Thread.
         thread->SetCondVarWaitAddress(0);
+        current_process->RemoveConditionVariableThread(thread);
 
         const std::size_t current_core = system.CurrentCoreIndex();
         auto& monitor = system.Monitor();
diff --git a/src/core/hle/kernel/thread.cpp b/src/core/hle/kernel/thread.cpp
index ee7531f2d5..6dafa311d2 100644
--- a/src/core/hle/kernel/thread.cpp
+++ b/src/core/hle/kernel/thread.cpp
@@ -306,8 +306,16 @@ void Thread::UpdatePriority() {
         return;
     }
 
+    if (GetStatus() == ThreadStatus::WaitCondVar) {
+        owner_process->RemoveConditionVariableThread(this);
+    }
+
     SetCurrentPriority(new_priority);
 
+    if (GetStatus() == ThreadStatus::WaitCondVar) {
+        owner_process->InsertConditionVariableThread(this);
+    }
+
     if (!lock_owner) {
         return;
     }
author	Fernando Sahmkow <fsahmkow27@gmail.com>	2019-11-14 20:13:18 -0400
committer	FernandoS27 <fsahmkow27@gmail.com>	2019-11-21 10:46:55 -0400
commit	2d16507f9fa06e868349d6f57a78585aec8628fd (patch)
tree	7931e2bb9db6d55e7be760f1a1dcff14de09db78 /src
parent	c52f37f259372485ac5902d9cae8de327c984a55 (diff)