rasterizer_cache: Refactor to support in-order flushing.

src/video_core/rasterizer_cache.h

@@ -15,45 +15,73 @@
 #include "video_core/rasterizer_interface.h"
 #include "video_core/renderer_base.h"
 
+class RasterizerCacheObject {
+public:
+    /// Gets the address of the shader in guest memory, required for cache management
+    virtual VAddr GetAddr() const = 0;
+
+    /// Gets the size of the shader in guest memory, required for cache management
+    virtual std::size_t GetSizeInBytes() const = 0;
+
+    /// Wriets any cached resources back to memory
+    virtual void Flush() = 0;
+
+    /// Sets whether the cached object should be considered registered
+    void SetIsRegistered(bool registered) {
+        is_registered = registered;
+    }
+
+    /// Returns true if the cached object is registered
+    bool IsRegistered() const {
+        return is_registered;
+    }
+
+    /// Returns true if the cached object is dirty
+    bool IsDirty() const {
+        return is_dirty;
+    }
+
+    /// Returns ticks from when this cached object was last modified
+    u64 GetLastModifiedTicks() const {
+        return last_modified_ticks;
+    }
+
+    /// Marks an object as recently modified, used to specify whether it is clean or dirty
+    template <class T>
+    void MarkAsModified(bool dirty, T& cache) {
+        is_dirty = dirty;
+        last_modified_ticks = cache.GetModifiedTicks();
+    }
+
+private:
+    bool is_registered{};      ///< Whether the object is currently registered with the cache
+    bool is_dirty{};           ///< Whether the object is dirty (out of sync with guest memory)
+    u64 last_modified_ticks{}; ///< When the object was last modified, used for in-order flushing
+};
+
 template <class T>
 class RasterizerCache : NonCopyable {
+    friend class RasterizerCacheObject;
+
 public:
-    /// Write any cached resources overlapping the region back to memory (if dirty)
+    /// Write any cached resources overlapping the specified region back to memory
     void FlushRegion(Tegra::GPUVAddr addr, size_t size) {
-        if (size == 0)
-            return;
-
-        const ObjectInterval interval{addr, addr + size};
-        for (auto& pair : boost::make_iterator_range(object_cache.equal_range(interval))) {
-            for (auto& cached_object : pair.second) {
-                if (!cached_object)
-                    continue;
-
-                cached_object->Flush();
-            }
+        const auto& objects{GetSortedObjectsFromRegion(addr, size)};
+        for (auto& object : objects) {
+            FlushObject(object);
         }
     }
 
     /// Mark the specified region as being invalidated
     void InvalidateRegion(VAddr addr, u64 size) {
-        if (size == 0)
-            return;
-
-        const ObjectInterval interval{addr, addr + size};
-        for (auto& pair : boost::make_iterator_range(object_cache.equal_range(interval))) {
-            for (auto& cached_object : pair.second) {
-                if (!cached_object)
-                    continue;
-
-                remove_objects.emplace(cached_object);
+        const auto& objects{GetSortedObjectsFromRegion(addr, size)};
+        for (auto& object : objects) {
+            if (!object->IsRegistered()) {
+                // Skip duplicates
+                continue;
             }
+            Unregister(object);
         }
-
-        for (auto& remove_object : remove_objects) {
-            Unregister(remove_object);
-        }
-
-        remove_objects.clear();
     }
 
     /// Invalidates everything in the cache
@@ -79,6 +107,7 @@ protected:
 
     /// Register an object into the cache
     void Register(const T& object) {
+        object->SetIsRegistered(true);
         object_cache.add({GetInterval(object), ObjectSet{object}});
         auto& rasterizer = Core::System::GetInstance().Renderer().Rasterizer();
         rasterizer.UpdatePagesCachedCount(object->GetAddr(), object->GetSizeInBytes(), 1);
@@ -86,18 +115,57 @@ protected:
 
     /// Unregisters an object from the cache
     void Unregister(const T& object) {
+        object->SetIsRegistered(false);
         auto& rasterizer = Core::System::GetInstance().Renderer().Rasterizer();
         rasterizer.UpdatePagesCachedCount(object->GetAddr(), object->GetSizeInBytes(), -1);
 
+        // Only flush if use_accurate_framebuffers is enabled, as it incurs a performance hit
         if (Settings::values.use_accurate_framebuffers) {
-            // Only flush if use_accurate_framebuffers is enabled, as it incurs a performance hit
-            object->Flush();
+            FlushObject(object);
         }
 
         object_cache.subtract({GetInterval(object), ObjectSet{object}});
     }
 
+    /// Returns a ticks counter used for tracking when cached objects were last modified
+    u64 GetModifiedTicks() {
+        return ++modified_ticks;
+    }
+
 private:
+    /// Returns a list of cached objects from the specified memory region, ordered by access time
+    std::vector<T> GetSortedObjectsFromRegion(VAddr addr, u64 size) {
+        if (size == 0) {
+            return {};
+        }
+
+        std::vector<T> objects;
+        const ObjectInterval interval{addr, addr + size};
+        for (auto& pair : boost::make_iterator_range(object_cache.equal_range(interval))) {
+            for (auto& cached_object : pair.second) {
+                if (!cached_object) {
+                    continue;
+                }
+                objects.push_back(cached_object);
+            }
+        }
+
+        std::sort(objects.begin(), objects.end(), [](const T& a, const T& b) -> bool {
+            return a->GetLastModifiedTicks() < b->GetLastModifiedTicks();
+        });
+
+        return objects;
+    }
+
+    /// Flushes the specified object, updating appropriate cache state as needed
+    void FlushObject(const T& object) {
+        if (!object->IsDirty()) {
+            return;
+        }
+        object->Flush();
+        object->MarkAsModified(false, *this);
+    }
+
     using ObjectSet = std::set<T>;
     using ObjectCache = boost::icl::interval_map<VAddr, ObjectSet>;
     using ObjectInterval = typename ObjectCache::interval_type;
@@ -107,6 +175,6 @@ private:
                                           object->GetAddr() + object->GetSizeInBytes());
     }
 
-    ObjectCache object_cache;
-    ObjectSet remove_objects;
+    ObjectCache object_cache; ///< Cache of objects
+    u64 modified_ticks{};     ///< Counter of cache state ticks, used for in-order flushing
 };