Reland "Reland "SkSurface asynchronous read APIs allow client to extend pixel lifetime""
This is a reland of 6fc04f88a89ed2c9a1b4aa48bcd28602a69a457b
Original change's description:
> Reland "SkSurface asynchronous read APIs allow client to extend pixel lifetime"
>
> This is a reland of ce240cc6fd8ec95bd051c7df2173dad2ae8f6ad6
>
> Original change's description:
> > SkSurface asynchronous read APIs allow client to extend pixel lifetime
> >
> > Previously the pixel data passed to the client was only valid during
> > the client's callback. This meant if the client wanted to defer
> > processing of the data a copy was necessary.
> >
> > Now we pass an object to the callback and the pixel lifetime is tied
> > to the lifetime of that object.
> >
> > The object may be holding a GPU transfer buffer mapped. We don't assume
> > that the object will be released on the direct GrContext thread. So
> > when the object is destroyed it posts a message to a new type,
> > GrClientMappedBufferManager, hanging off the direct context. The direct
> > context will periodically check for messages and unmap and then unref
> > buffers so that they can be reused. Currently this is done in
> > GrContext::performDeferredCleanup() and GrDrawingManager::flush().
> >
> > The old API is kept around for backwards compatibility but it is
> > reimplemented as a bridge on top of the new mechanism.
> >
> > Also a utility function to SkImageInfo is added to directly make a new
> > info with a specified dimensions rather than passing the width and
> > height separately to makeWH().
> >
> > Bug: chromium:973403
> > Bug: skia:8962
> >
> > Change-Id: Id5cf04235376170142a48e90d3ecd13fd021a2a6
> > Reviewed-on: https://skia-review.googlesource.com/c/skia/+/245457
> > Reviewed-by: Brian Osman <brianosman@google.com>
> > Commit-Queue: Brian Salomon <bsalomon@google.com>
>
> Bug: chromium:973403, skia:8962
> Change-Id: I5cecd36276c8b6dc942cf549c7095db2df88530c
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/245678
> Reviewed-by: Brian Salomon <bsalomon@google.com>
> Commit-Queue: Brian Salomon <bsalomon@google.com>
Bug: chromium:973403, skia:8962
Change-Id: Ie584c1c3ef8021c976f71b708e53871c693cc450
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/246057
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
diff --git a/src/gpu/GrClientMappedBufferManager.cpp b/src/gpu/GrClientMappedBufferManager.cpp
new file mode 100644
index 0000000..b927726
--- /dev/null
+++ b/src/gpu/GrClientMappedBufferManager.cpp
@@ -0,0 +1,71 @@
+/*
+ * Copyright 2019 Google LLC
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "src/gpu/GrClientMappedBufferManager.h"
+
+#include <algorithm>
+
+GrClientMappedBufferManager::GrClientMappedBufferManager(uint32_t contextID)
+ : fFinishedBufferInbox(contextID) {}
+
+GrClientMappedBufferManager::~GrClientMappedBufferManager() {
+ this->process();
+ if (!fAbandoned) {
+ // If we're going down before we got the messages we go ahead and unmap all the buffers.
+ // It's up to the client to ensure that they aren't being accessed on another thread while
+ // this is happening (or afterwards on any thread).
+ for (auto& b : fClientHeldBuffers) {
+ b->unmap();
+ }
+ }
+}
+
+void GrClientMappedBufferManager::insert(sk_sp<GrGpuBuffer> b) {
+ SkDEBUGCODE(auto end = fClientHeldBuffers.end());
+ SkASSERT(std::find(fClientHeldBuffers.begin(), end, b) == end);
+ fClientHeldBuffers.emplace_front(std::move(b));
+}
+
+void GrClientMappedBufferManager::process() {
+ SkSTArray<4, BufferFinishedMessage> messages;
+ fFinishedBufferInbox.poll(&messages);
+ if (!fAbandoned) {
+ for (auto& m : messages) {
+ this->remove(m.fBuffer);
+ m.fBuffer->unmap();
+ }
+ }
+}
+
+void GrClientMappedBufferManager::abandon() {
+ fAbandoned = true;
+ fClientHeldBuffers.clear();
+}
+
+void GrClientMappedBufferManager::remove(const sk_sp<GrGpuBuffer>& b) {
+ // There is no convenient remove only the first element that equals a value functionality in
+ // std::forward_list.
+ auto prev = fClientHeldBuffers.before_begin();
+ auto end = fClientHeldBuffers.end();
+ SkASSERT(std::find(fClientHeldBuffers.begin(), end, b) != end);
+ for (auto cur = fClientHeldBuffers.begin(); cur != end; prev = cur++) {
+ if (*cur == b) {
+ fClientHeldBuffers.erase_after(prev);
+ break;
+ }
+ }
+ SkASSERT(std::find(fClientHeldBuffers.begin(), end, b) == end);
+}
+
+//////////////////////////////////////////////////////////////////////////////
+
+DECLARE_SKMESSAGEBUS_MESSAGE(GrClientMappedBufferManager::BufferFinishedMessage)
+
+bool SkShouldPostMessageToBus(const GrClientMappedBufferManager::BufferFinishedMessage& m,
+ uint32_t msgBusUniqueID) {
+ return m.fInboxID == msgBusUniqueID;
+}