Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 288 insertions, 0 deletions

diff --git a/gfx/layers/SurfacePoolCA.h b/gfx/layers/SurfacePoolCA.h
new file mode 100644
index 0000000000..97344f7d06
--- /dev/null
+++ b/gfx/layers/SurfacePoolCA.h
@@ -0,0 +1,288 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_layers_SurfacePoolCA_h
+#define mozilla_layers_SurfacePoolCA_h
+
+#include <IOSurface/IOSurface.h>
+
+#include <deque>
+#include <unordered_map>
+
+#include "mozilla/Atomics.h"
+#include "mozilla/DataMutex.h"
+
+#include "mozilla/layers/SurfacePool.h"
+#include "CFTypeRefPtr.h"
+#include "MozFramebuffer.h"
+#include "nsISupportsImpl.h"
+
+namespace mozilla {
+
+namespace gl {
+class MozFramebuffer;
+}  // namespace gl
+
+namespace layers {
+
+class SurfacePoolHandleCA;
+struct SurfacePoolCAWrapperForGL;
+
+// An implementation of SurfacePool for IOSurfaces and GL framebuffers.
+// The goal of having this pool is to avoid creating and destroying IOSurfaces
+// and framebuffers frequently, because doing so is expensive.
+// SurfacePoolCA is threadsafe. All its data is wrapped inside LockedPool, and
+// each access to LockedPool is guarded with a lock through DataMutex.
+//
+// The pool satisfies the following requirements:
+//  - It can be shared across windows, even across windows with different
+//  GLContexts.
+//  - The number of unused surfaces that are available for recycling is capped
+//  to a fixed value per pool, regardless of how many windows use that pool.
+//  - When all windows are closed (all handles are gone), no surfaces are kept
+//  alive (the pool is destroyed).
+//  - There is an explicit way of deleting GL resources for a GLContext so that
+//  it can happen at a deterministic time on the right thread.
+//  - Additionally, once a GLContext is no longer being used in any window
+//  (really: any pool handle), all surface-associated GL resources of that
+//  context are destroyed.
+//  - For every IOSurface, only one set of GL resources is in existence at any
+//  given time. We don't want there to be framebuffers in two different
+//  GLContexts for one surface.
+//  - We do not want to recycle an IOSurface that currently has GL resources of
+//  context A for a pool handle that uses context B.
+//  - We need to delay IOSurface recycling until the window server is done with
+//  the surface (`!IOSurfaceIsInUse(surf)`)
+class SurfacePoolCA final : public SurfacePool {
+ public:
+  // Get a handle for a new window. aGL can be nullptr.
+  RefPtr<SurfacePoolHandle> GetHandleForGL(gl::GLContext* aGL) override;
+
+  // Destroy all GL resources associated with aGL managed by this pool.
+  void DestroyGLResourcesForContext(gl::GLContext* aGL) override;
+
+ private:
+  friend struct SurfacePoolCAWrapperForGL;
+  friend class SurfacePoolHandleCA;
+  friend RefPtr<SurfacePool> SurfacePool::Create(size_t aPoolSizeLimit);
+
+  explicit SurfacePoolCA(size_t aPoolSizeLimit);
+  ~SurfacePoolCA() override;
+
+  // Get an existing surface of aSize from the pool or create a new surface.
+  // The returned surface is guaranteed not to be in use by the window server.
+  CFTypeRefPtr<IOSurfaceRef> ObtainSurfaceFromPool(const gfx::IntSize& aSize,
+                                                   gl::GLContext* aGL);
+
+  // Place a surface that was previously obtained from this pool back into the
+  // pool. aSurface may or may not be in use by the window server.
+  void ReturnSurfaceToPool(CFTypeRefPtr<IOSurfaceRef> aSurface);
+
+  // Re-run checks whether the window server still uses IOSurfaces which are
+  // eligible for recycling. The purpose of the "generation" counter is to
+  // reduce the number of calls to IOSurfaceIsInUse in a scenario where many
+  // windows / handles are calling CollectPendingSurfaces in the same frame
+  // (i.e. multiple simultaneously-animating windows).
+  uint64_t CollectPendingSurfaces(uint64_t aCheckGenerationsUpTo);
+
+  // Enforce the pool size limit by evicting surfaces as necessary. This should
+  // happen at the end of the frame so that we can temporarily exceed the limit
+  // within a frame.
+  void EnforcePoolSizeLimit();
+
+  // Get or create the framebuffer for the given surface and GL context.
+  // The returned framebuffer handle will become invalid once
+  // DestroyGLResourcesForContext or DecrementGLContextHandleCount are called.
+  // The framebuffer's depth buffer (if present) may be shared between multiple
+  // framebuffers! Do not assume anything about the depth buffer's existing
+  // contents (i.e. clear it at the beginning of the draw), and do not
+  // interleave drawing commands to different framebuffers in such a way that
+  // the shared depth buffer could cause trouble.
+  Maybe<GLuint> GetFramebufferForSurface(CFTypeRefPtr<IOSurfaceRef> aSurface,
+                                         gl::GLContext* aGL,
+                                         bool aNeedsDepthBuffer);
+
+  // Called by the destructor of SurfacePoolCAWrapperForGL so that we can clear
+  // our weak reference to it and delete GL resources.
+  void OnWrapperDestroyed(gl::GLContext* aGL,
+                          SurfacePoolCAWrapperForGL* aWrapper);
+
+  // The actual pool implementation lives in LockedPool, which is accessed in
+  // a thread-safe manner.
+  struct LockedPool {
+    explicit LockedPool(size_t aPoolSizeLimit);
+    LockedPool(LockedPool&&) = default;
+    ~LockedPool();
+
+    RefPtr<SurfacePoolCAWrapperForGL> GetWrapperForGL(SurfacePoolCA* aPool,
+                                                      gl::GLContext* aGL);
+    void DestroyGLResourcesForContext(gl::GLContext* aGL);
+
+    CFTypeRefPtr<IOSurfaceRef> ObtainSurfaceFromPool(const gfx::IntSize& aSize,
+                                                     gl::GLContext* aGL);
+    void ReturnSurfaceToPool(CFTypeRefPtr<IOSurfaceRef> aSurface);
+    uint64_t CollectPendingSurfaces(uint64_t aCheckGenerationsUpTo);
+    void EnforcePoolSizeLimit();
+    Maybe<GLuint> GetFramebufferForSurface(CFTypeRefPtr<IOSurfaceRef> aSurface,
+                                           gl::GLContext* aGL,
+                                           bool aNeedsDepthBuffer);
+    void OnWrapperDestroyed(gl::GLContext* aGL,
+                            SurfacePoolCAWrapperForGL* aWrapper);
+    uint64_t EstimateTotalMemory();
+
+    uint64_t mCollectionGeneration = 0;
+
+   protected:
+    struct GLResourcesForSurface {
+      RefPtr<gl::GLContext> mGLContext;            // non-null
+      UniquePtr<gl::MozFramebuffer> mFramebuffer;  // non-null
+    };
+
+    struct SurfacePoolEntry {
+      gfx::IntSize mSize;
+      CFTypeRefPtr<IOSurfaceRef> mIOSurface;  // non-null
+      Maybe<GLResourcesForSurface> mGLResources;
+    };
+
+    struct PendingSurfaceEntry {
+      SurfacePoolEntry mEntry;
+      // The value of LockedPool::mCollectionGeneration at the time
+      // IOSurfaceIsInUse was last called for mEntry.mIOSurface.
+      uint64_t mPreviousCheckGeneration;
+      // The number of times an IOSurfaceIsInUse check has been performed.
+      uint64_t mCheckCount;
+    };
+
+    template <typename F>
+    void MutateEntryStorage(const char* aMutationType,
+                            const gfx::IntSize& aSize, F aFn);
+
+    template <typename F>
+    void ForEachEntry(F aFn);
+
+    bool CanRecycleSurfaceForRequest(const SurfacePoolEntry& aEntry,
+                                     const gfx::IntSize& aSize,
+                                     gl::GLContext* aGL);
+
+    RefPtr<gl::DepthAndStencilBuffer> GetDepthBufferForSharing(
+        gl::GLContext* aGL, const gfx::IntSize& aSize);
+    UniquePtr<gl::MozFramebuffer> CreateFramebufferForTexture(
+        gl::GLContext* aGL, const gfx::IntSize& aSize, GLuint aTexture,
+        bool aNeedsDepthBuffer);
+
+    // Every IOSurface that is managed by the pool is wrapped in a
+    // SurfacePoolEntry object. Every entry is stored in one of three buckets at
+    // any given time: mInUseEntries, mPendingEntries, or mAvailableEntries. All
+    // mutations to these buckets are performed via calls to
+    // MutateEntryStorage(). Entries can move between the buckets in the
+    // following ways:
+    //
+    //                                [new]
+    //                                  | Create
+    //                                  v
+    //    +----------------------------------------------------------------+
+    //    |                       mInUseEntries                            |
+    //    +------+------------------------------+--------------------------+
+    //           |            ^                 | Start waiting for
+    //           |            | Recycle         v
+    //           |            |              +-----------------------------+
+    //           |            |              |       mPendingEntries       |
+    //           |            |              +--+--------------------+-----+
+    //           | Retain     |                 | Stop waiting for   |
+    //           v            |                 v                    |
+    //    +-------------------+-------------------------+            |
+    //    |              mAvailableEntries              |            |
+    //    +-----------------------------+---------------+            |
+    //                                  | Evict                      | Eject
+    //                                  v                            v
+    //                             [destroyed]                  [destroyed]
+    //
+    // Each arrow corresponds to one invocation of MutateEntryStorage() with the
+    // arrow's label passed as the aMutationType string parameter.
+
+    // Stores the entries for surfaces that are in use by NativeLayerCA, i.e. an
+    // entry is inside mInUseEntries between calls to ObtainSurfaceFromPool()
+    // and ReturnSurfaceToPool().
+    std::unordered_map<CFTypeRefPtr<IOSurfaceRef>, SurfacePoolEntry>
+        mInUseEntries;
+
+    // Stores entries which are no longer in use by NativeLayerCA but are still
+    // in use by the window server, i.e. for which
+    // IOSurfaceIsInUse(pendingSurfaceEntry.mEntry.mIOSurface.get()) still
+    // returns true. These entries are checked once per frame inside
+    // CollectPendingSurfaces(), and returned to mAvailableEntries once the
+    // window server is done.
+    nsTArray<PendingSurfaceEntry> mPendingEntries;
+
+    // Stores entries which are available for recycling. These entries are not
+    // in use by a NativeLayerCA or by the window server.
+    nsTArray<SurfacePoolEntry> mAvailableEntries;
+
+    // Keeps weak references to SurfacePoolCAWrapperForGL instances.
+    // For each GLContext* value (including nullptr), only one wrapper can
+    // exist at any time. The wrapper keeps a strong reference to us and
+    // notifies us when it gets destroyed. At that point we can call
+    // DestroyGLResourcesForContext because we know no other SurfaceHandles for
+    // that context exist.
+    std::unordered_map<gl::GLContext*, SurfacePoolCAWrapperForGL*> mWrappers;
+    size_t mPoolSizeLimit = 0;
+
+    struct DepthBufferEntry {
+      RefPtr<gl::GLContext> mGLContext;
+      gfx::IntSize mSize;
+      WeakPtr<gl::DepthAndStencilBuffer> mBuffer;
+    };
+
+    nsTArray<DepthBufferEntry> mDepthBuffers;
+  };
+
+  DataMutex<LockedPool> mPool;
+};
+
+// One process-wide instance per (SurfacePoolCA*, GLContext*) pair.
+// Keeps the SurfacePool alive, and the SurfacePool has a weak reference to the
+// wrapper so that it can ensure that there's only one wrapper for it per
+// GLContext* at any time.
+struct SurfacePoolCAWrapperForGL {
+  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(SurfacePoolCAWrapperForGL);
+
+  const RefPtr<SurfacePoolCA> mPool;  // non-null
+  const RefPtr<gl::GLContext> mGL;    // can be null
+
+  SurfacePoolCAWrapperForGL(SurfacePoolCA* aPool, gl::GLContext* aGL)
+      : mPool(aPool), mGL(aGL) {}
+
+ protected:
+  ~SurfacePoolCAWrapperForGL() { mPool->OnWrapperDestroyed(mGL, this); }
+};
+
+// A surface pool handle that is stored on NativeLayerCA and keeps the
+// SurfacePool alive.
+class SurfacePoolHandleCA final : public SurfacePoolHandle {
+ public:
+  SurfacePoolHandleCA* AsSurfacePoolHandleCA() override { return this; }
+  const auto& gl() { return mPoolWrapper->mGL; }
+  CFTypeRefPtr<IOSurfaceRef> ObtainSurfaceFromPool(const gfx::IntSize& aSize);
+  void ReturnSurfaceToPool(CFTypeRefPtr<IOSurfaceRef> aSurface);
+  Maybe<GLuint> GetFramebufferForSurface(CFTypeRefPtr<IOSurfaceRef> aSurface,
+                                         bool aNeedsDepthBuffer);
+  RefPtr<SurfacePool> Pool() override { return mPoolWrapper->mPool; }
+  void OnBeginFrame() override;
+  void OnEndFrame() override;
+
+ private:
+  friend class SurfacePoolCA;
+  SurfacePoolHandleCA(RefPtr<SurfacePoolCAWrapperForGL>&& aPoolWrapper,
+                      uint64_t aCurrentCollectionGeneration);
+  ~SurfacePoolHandleCA() override;
+
+  const RefPtr<SurfacePoolCAWrapperForGL> mPoolWrapper;
+  DataMutex<uint64_t> mPreviousFrameCollectionGeneration;
+};
+
+}  // namespace layers
+}  // namespace mozilla
+
+#endif  // mozilla_layers_SurfacePoolCA_h