os: implement SdkRecursiveMutex

libraries/libstratosphere/include/stratosphere/os.hpp

@@ -29,6 +29,7 @@
 #include <stratosphere/os/os_mutex.hpp>
 #include <stratosphere/os/os_condition_variable.hpp>
 #include <stratosphere/os/os_sdk_mutex.hpp>
+#include <stratosphere/os/os_sdk_recursive_mutex.hpp>
 #include <stratosphere/os/os_sdk_condition_variable.hpp>
 #include <stratosphere/os/os_busy_mutex.hpp>
 #include <stratosphere/os/os_rw_busy_mutex.hpp>

libraries/libstratosphere/include/stratosphere/os/os_sdk_condition_variable.hpp

@@ -17,6 +17,7 @@
 #pragma once
 #include <vapours.hpp>
 #include <stratosphere/os/os_sdk_mutex.hpp>
+#include <stratosphere/os/os_sdk_recursive_mutex.hpp>
 #include <stratosphere/os/impl/os_internal_condition_variable.hpp>
 
 namespace ams::os {
@@ -27,20 +28,21 @@ namespace ams::os {
             impl::InternalConditionVariableStorage _storage;
         };
 
-        void Initialize() {
+        ALWAYS_INLINE void Initialize() {
             GetReference(this->_storage).Initialize();
         }
 
         void Wait(SdkMutexType &mutex);
         bool TimedWait(SdkMutexType &mutex, TimeSpan timeout);
 
-        /* TODO: SdkRecursiveMutexType */
+        void Wait(SdkRecursiveMutexType &mutex);
+        bool TimedWait(SdkRecursiveMutexType &mutex, TimeSpan timeout);
 
-        void Signal() {
+        ALWAYS_INLINE void Signal() {
             GetReference(this->_storage).Signal();
         }
 
-        void Broadcast() {
+        ALWAYS_INLINE void Broadcast() {
             GetReference(this->_storage).Broadcast();
         }
     };
@@ -48,26 +50,32 @@ namespace ams::os {
 
     class SdkConditionVariable {
         private:
-            SdkConditionVariableType cv;
+            SdkConditionVariableType m_cv;
         public:
-            constexpr SdkConditionVariable() : cv{{0}} { /* ... */ }
+            constexpr SdkConditionVariable() : m_cv{{0}} { /* ... */ }
 
-            void Wait(SdkMutex &m) {
-                return this->cv.Wait(m.mutex);
+            ALWAYS_INLINE void Wait(SdkMutex &m) {
+                return m_cv.Wait(m.m_mutex);
             }
 
-            bool TimedWait(SdkMutex &m, TimeSpan timeout) {
-                return this->cv.TimedWait(m.mutex, timeout);
+            ALWAYS_INLINE bool TimedWait(SdkMutex &m, TimeSpan timeout) {
+                return m_cv.TimedWait(m.m_mutex, timeout);
             }
 
-            /* TODO: SdkRecursiveMutexType */
-
-            void Signal() {
-                return this->cv.Signal();
+            ALWAYS_INLINE void Wait(SdkRecursiveMutex &m) {
+                return m_cv.Wait(m.m_mutex);
             }
 
-            void Broadcast() {
-                return this->cv.Broadcast();
+            ALWAYS_INLINE bool TimedWait(SdkRecursiveMutex &m, TimeSpan timeout) {
+                return m_cv.TimedWait(m.m_mutex, timeout);
+            }
+
+            ALWAYS_INLINE void Signal() {
+                return m_cv.Signal();
+            }
+
+            ALWAYS_INLINE void Broadcast() {
+                return m_cv.Broadcast();
             }
     };
 

libraries/libstratosphere/include/stratosphere/os/os_sdk_mutex.hpp

@@ -42,15 +42,15 @@ namespace ams::os {
         private:
             friend class SdkConditionVariable;
         private:
-            SdkMutexType mutex;
+            SdkMutexType m_mutex;
         public:
-            constexpr SdkMutex() : mutex{{0}} { /* ... */ }
+            constexpr SdkMutex() : m_mutex{{0}} { /* ... */ }
 
-            ALWAYS_INLINE void Lock()    { return os::LockSdkMutex(std::addressof(this->mutex)); }
-            ALWAYS_INLINE bool TryLock() { return os::TryLockSdkMutex(std::addressof(this->mutex)); }
-            ALWAYS_INLINE void Unlock()  { return os::UnlockSdkMutex(std::addressof(this->mutex)); }
+            ALWAYS_INLINE void Lock()    { return os::LockSdkMutex(std::addressof(m_mutex)); }
+            ALWAYS_INLINE bool TryLock() { return os::TryLockSdkMutex(std::addressof(m_mutex)); }
+            ALWAYS_INLINE void Unlock()  { return os::UnlockSdkMutex(std::addressof(m_mutex)); }
 
-            ALWAYS_INLINE bool IsLockedByCurrentThread() const { return os::IsSdkMutexLockedByCurrentThread(std::addressof(this->mutex)); }
+            ALWAYS_INLINE bool IsLockedByCurrentThread() const { return os::IsSdkMutexLockedByCurrentThread(std::addressof(m_mutex)); }
 
             ALWAYS_INLINE void lock()     { return this->Lock(); }
             ALWAYS_INLINE bool try_lock() { return this->TryLock(); }

libraries/libstratosphere/include/stratosphere/os/os_sdk_recursive_mutex.hpp

@@ -0,0 +1,61 @@
+/*
+ * Copyright (c) 2018-2020 Atmosphère-NX
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+#include <vapours.hpp>
+#include <stratosphere/os/impl/os_internal_critical_section.hpp>
+
+namespace ams::os {
+
+    class SdkConditionVariable;
+
+    struct SdkRecursiveMutexType {
+        union {
+            s32 _arr[sizeof(impl::InternalCriticalSectionStorage) / sizeof(s32)];
+            impl::InternalCriticalSectionStorage _storage;
+        };
+        u32 recursive_count;
+    };
+    static_assert(std::is_trivial<SdkRecursiveMutexType>::value);
+
+    void InitializeSdkRecursiveMutex(SdkRecursiveMutexType *rmutex);
+
+    void LockSdkRecursiveMutex(SdkRecursiveMutexType *rmutex);
+    bool TryLockSdkRecursiveMutex(SdkRecursiveMutexType *rmutex);
+    void UnlockSdkRecursiveMutex(SdkRecursiveMutexType *rmutex);
+
+    bool IsSdkRecursiveMutexLockedByCurrentThread(const SdkRecursiveMutexType *rmutex);
+
+    class SdkRecursiveMutex {
+        private:
+            friend class SdkConditionVariable;
+        private:
+            SdkRecursiveMutexType m_mutex;
+        public:
+            constexpr SdkRecursiveMutex() : m_mutex{{0}, 0} { /* ... */ }
+
+            ALWAYS_INLINE void Lock()    { return os::LockSdkRecursiveMutex(std::addressof(m_mutex)); }
+            ALWAYS_INLINE bool TryLock() { return os::TryLockSdkRecursiveMutex(std::addressof(m_mutex)); }
+            ALWAYS_INLINE void Unlock()  { return os::UnlockSdkRecursiveMutex(std::addressof(m_mutex)); }
+
+            ALWAYS_INLINE bool IsLockedByCurrentThread() const { return os::IsSdkRecursiveMutexLockedByCurrentThread(std::addressof(m_mutex)); }
+
+            ALWAYS_INLINE void lock()     { return this->Lock(); }
+            ALWAYS_INLINE bool try_lock() { return this->TryLock(); }
+            ALWAYS_INLINE void unlock()   { return this->Unlock(); }
+    };
+
+}

libraries/libstratosphere/source/os/os_sdk_condition_variable.cpp

@@ -45,4 +45,58 @@ namespace ams::os {
         return status == ConditionVariableStatus::Success;
     }
 
+    void SdkConditionVariableType::Wait(SdkRecursiveMutexType &mutex) {
+        /* Check preconditions. */
+        AMS_ABORT_UNLESS(os::IsSdkRecursiveMutexLockedByCurrentThread(std::addressof(mutex)));
+        AMS_ABORT_UNLESS(mutex.recursive_count == 1);
+
+        /* Decrement the mutex's recursive count. */
+        --mutex.recursive_count;
+
+        /* Wait on the mutex. */
+        GetReference(this->_storage).Wait(GetPointer(mutex._storage));
+
+        /* Increment the mutex's recursive count. */
+        ++mutex.recursive_count;
+
+        /* Check that the mutex's recursive count is valid. */
+        AMS_ABORT_UNLESS(mutex.recursive_count != 0);
+    }
+
+    bool SdkConditionVariableType::TimedWait(SdkRecursiveMutexType &mutex, TimeSpan timeout) {
+        /* Check preconditions. */
+        AMS_ASSERT(timeout.GetNanoSeconds() >= 0);
+        AMS_ABORT_UNLESS(os::IsSdkRecursiveMutexLockedByCurrentThread(std::addressof(mutex)));
+
+        /* Handle zero timeout by unlocking and re-locking. */
+        if (timeout == TimeSpan(0)) {
+            /* NOTE: Nintendo doesn't check recursive_count here...seems really suspicious? */
+            /*       Not sure that this is correct, or if they just forgot to check. */
+            GetReference(mutex._storage).Leave();
+            GetReference(mutex._storage).Enter();
+            return false;
+        }
+
+        /* Check that the mutex is held exactly once. */
+        AMS_ABORT_UNLESS(mutex.recursive_count == 1);
+
+        /* Decrement the mutex's recursive count. */
+        --mutex.recursive_count;
+
+        /* Create timeout helper. */
+        impl::TimeoutHelper timeout_helper(timeout);
+
+        /* Perform timed wait. */
+        auto status = GetReference(this->_storage).TimedWait(GetPointer(mutex._storage), timeout_helper);
+
+        /* Increment the mutex's recursive count. */
+        ++mutex.recursive_count;
+
+        /* Check that the mutex's recursive count is valid. */
+        AMS_ABORT_UNLESS(mutex.recursive_count != 0);
+
+        /* Return whether we succeeded. */
+        return status == ConditionVariableStatus::Success;
+    }
+
 }

libraries/libstratosphere/source/os/os_sdk_mutex.cpp

@@ -18,25 +18,36 @@
 namespace ams::os {
 
     void InitializeSdkMutex(SdkMutexType *mutex) {
+        /* Initialize the critical section. */
         GetReference(mutex->_storage).Initialize();
     }
 
     bool IsSdkMutexLockedByCurrentThread(const SdkMutexType *mutex) {
+        /* Check whether the critical section is held. */
         return GetReference(mutex->_storage).IsLockedByCurrentThread();
     }
 
     void LockSdkMutex(SdkMutexType *mutex) {
+        /* Check pre-conditions. */
         AMS_ABORT_UNLESS(!IsSdkMutexLockedByCurrentThread(mutex));
+
+        /* Enter the critical section. */
         return GetReference(mutex->_storage).Enter();
     }
 
     bool TryLockSdkMutex(SdkMutexType *mutex) {
+        /* Check pre-conditions. */
         AMS_ABORT_UNLESS(!IsSdkMutexLockedByCurrentThread(mutex));
+
+        /* Try to enter the critical section. */
         return GetReference(mutex->_storage).TryEnter();
     }
 
     void UnlockSdkMutex(SdkMutexType *mutex) {
+        /* Check pre-conditions. */
         AMS_ABORT_UNLESS(IsSdkMutexLockedByCurrentThread(mutex));
+
+        /* Leave the critical section. */
         return GetReference(mutex->_storage).Leave();
     }
 

libraries/libstratosphere/source/os/os_sdk_recursive_mutex.cpp

@@ -0,0 +1,69 @@
+/*
+ * Copyright (c) 2018-2020 Atmosphère-NX
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <stratosphere.hpp>
+
+namespace ams::os {
+
+    void InitializeSdkRecursiveMutex(SdkRecursiveMutexType *rmutex) {
+        /* Initialize the critical section. */
+        GetReference(rmutex->_storage).Initialize();
+
+        /* Set recursive count. */
+        rmutex->recursive_count = 0;
+    }
+
+    bool IsSdkRecursiveMutexLockedByCurrentThread(const SdkRecursiveMutexType *rmutex) {
+        /* Check whether the critical section is held. */
+        return GetReference(rmutex->_storage).IsLockedByCurrentThread();
+    }
+
+    void LockSdkRecursiveMutex(SdkRecursiveMutexType *rmutex) {
+        /* If we don't hold the mutex, enter the critical section. */
+        if (!IsSdkRecursiveMutexLockedByCurrentThread(rmutex)) {
+            GetReference(rmutex->_storage).Enter();
+        }
+
+        /* Increment (and check) recursive count. */
+        ++rmutex->recursive_count;
+        AMS_ABORT_UNLESS(rmutex->recursive_count != 0);
+    }
+
+    bool TryLockSdkRecursiveMutex(SdkRecursiveMutexType *rmutex) {
+        /* If we don't hold the mutex, try to enter the critical section. */
+        if (!IsSdkRecursiveMutexLockedByCurrentThread(rmutex)) {
+            if (!GetReference(rmutex->_storage).TryEnter()) {
+                return false;
+            }
+        }
+
+        /* Increment (and check) recursive count. */
+        ++rmutex->recursive_count;
+        AMS_ABORT_UNLESS(rmutex->recursive_count != 0);
+
+        return true;
+    }
+
+    void UnlockSdkRecursiveMutex(SdkRecursiveMutexType *rmutex) {
+        /* Check pre-conditions. */
+        AMS_ABORT_UNLESS(IsSdkRecursiveMutexLockedByCurrentThread(rmutex));
+
+        /* Decrement recursive count, and leave critical section if we no longer hold the mutex. */
+        if ((--rmutex->recursive_count) == 0) {
+            GetReference(rmutex->_storage).Leave();
+        }
+    }
+
+}