From a4650a50a0b35e9e4342d6600b6eb24fd94bb8e5 Mon Sep 17 00:00:00 2001
From: Dan Stoza <stoza@google.com>
Date: Tue, 12 May 2015 12:56:16 -0700
Subject: Fix PTS handling for buffer replacement

This changes the way that SurfaceFlinger's shadow buffer management
works such that instead of tracking the size of the shadow queue in the
BufferQueue, SF tracks the last frame number it has seen, and passes
that into the acquireBuffer call. BufferQueueConsumer then ensures that
it never returns a buffer newer than that frame number, even if that
means that it must return PRESENT_LATER for an otherwise valid buffer.

Change-Id: I3fcb45f683ed660c3f18a8b85ae1f8a962ba6f0e
---
 libs/gui/IGraphicBufferConsumer.cpp | 25 +++++--------------------
 1 file changed, 5 insertions(+), 20 deletions(-)

(limited to 'libs/gui/IGraphicBufferConsumer.cpp')

diff --git a/libs/gui/IGraphicBufferConsumer.cpp b/libs/gui/IGraphicBufferConsumer.cpp
index 480dfb646a..b86f4c5d23 100644
--- a/libs/gui/IGraphicBufferConsumer.cpp
+++ b/libs/gui/IGraphicBufferConsumer.cpp
@@ -52,7 +52,6 @@ enum {
     SET_CONSUMER_USAGE_BITS,
     SET_TRANSFORM_HINT,
     GET_SIDEBAND_STREAM,
-    SET_SHADOW_QUEUE_SIZE,
     DUMP,
 };
 
@@ -67,10 +66,12 @@ public:
 
     virtual ~BpGraphicBufferConsumer();
 
-    virtual status_t acquireBuffer(BufferItem *buffer, nsecs_t presentWhen) {
+    virtual status_t acquireBuffer(BufferItem *buffer, nsecs_t presentWhen,
+            uint64_t maxFrameNumber) {
         Parcel data, reply;
         data.writeInterfaceToken(IGraphicBufferConsumer::getInterfaceDescriptor());
         data.writeInt64(presentWhen);
+        data.writeUint64(maxFrameNumber);
         status_t result = remote()->transact(ACQUIRE_BUFFER, data, &reply);
         if (result != NO_ERROR) {
             return result;
@@ -270,17 +271,6 @@ public:
         return stream;
     }
 
-    virtual void setShadowQueueSize(size_t size) {
-        Parcel data, reply;
-        data.writeInterfaceToken(IGraphicBufferConsumer::getInterfaceDescriptor());
-        data.writeInt64(static_cast<int64_t>(size));
-        status_t result = remote()->transact(SET_SHADOW_QUEUE_SIZE, data, &reply);
-        if (result != NO_ERROR) {
-            ALOGE("setShadowQueueSize failed (%d)", result);
-            return;
-        }
-    }
-
     virtual void dump(String8& result, const char* prefix) const {
         Parcel data, reply;
         data.writeInterfaceToken(IGraphicBufferConsumer::getInterfaceDescriptor());
@@ -307,7 +297,8 @@ status_t BnGraphicBufferConsumer::onTransact(
             CHECK_INTERFACE(IGraphicBufferConsumer, data, reply);
             BufferItem item;
             int64_t presentWhen = data.readInt64();
-            status_t result = acquireBuffer(&item, presentWhen);
+            uint64_t maxFrameNumber = data.readUint64();
+            status_t result = acquireBuffer(&item, presentWhen, maxFrameNumber);
             status_t err = reply->write(item);
             if (err) return err;
             reply->writeInt32(result);
@@ -435,12 +426,6 @@ status_t BnGraphicBufferConsumer::onTransact(
             }
             return NO_ERROR;
         }
-        case SET_SHADOW_QUEUE_SIZE: {
-            CHECK_INTERFACE(IGraphicBufferConsumer, data, reply);
-            size_t size = static_cast<size_t>(data.readInt64());
-            setShadowQueueSize(size);
-            return NO_ERROR;
-        }
         case DUMP: {
             CHECK_INTERFACE(IGraphicBufferConsumer, data, reply);
             String8 result = data.readString8();
-- 
cgit v1.2.3-59-g8ed1b