Merge lp:~kdub/mir/rw-fences into lp:mir

[Kevin DuBois]

android: designate the buffer usage when attempting to access or update the fence associated with the native buffer. This lets us skip waiting if the buffer is being reserved for reading and a second read is needed.

Specifically, if HWC has a buffer onscreen, and then needs to use that same buffer in the composition of the next frame, it needs to be able to read from the onscreen-buffer to assemble the next frame. We account for this if the buffer was an overlay in frame 1 and and overlay in frame 2, but if its overlay in frame 1, and then gl fallback in frame 2, then we need read-only access for the texture upload.

fixes: lp: #1329868

android: designate the buffer usage when attempting to access or update the fence associated with the native buffer. This lets us skip waiting if the buffer is being reserved for reading and a second read is needed.

Specifically, if HWC has a buffer onscreen, and then needs to use that same buffer in the composition of the next frame, it needs to be able to read from the onscreen-buffer to assemble the next frame. We account for this if the buffer was an overlay in frame 1 and and overlay in frame 2, but if its overlay in frame 1, and then gl fallback in frame 2, then we need read-only access for the texture upload.

checked for tears with full unity stack on:
mx3, nex4, nex10

fixes: lp: #1329868

[PS Jenkins bot (ps-jenkins)]

FAILED: Continuous integration, rev:1700
http://jenkins.qa.ubuntu.com/job/mir-team-mir-development-branch-ci/1922/
Executed test runs:
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-android-utopic-i386-build/595
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-clang-utopic-amd64-build/601
    FAILURE: http://jenkins.qa.ubuntu.com/job/mir-mediumtests-utopic-touch/594/console
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-team-mir-development-branch-utopic-amd64-ci/443
        deb: http://jenkins.qa.ubuntu.com/job/mir-team-mir-development-branch-utopic-amd64-ci/443/artifact/work/output/*zip*/output.zip
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-team-mir-development-branch-utopic-armhf-ci/440
        deb: http://jenkins.qa.ubuntu.com/job/mir-team-mir-development-branch-utopic-armhf-ci/440/artifact/work/output/*zip*/output.zip
    SUCCESS: http://jenkins.qa.ubuntu.com/job/generic-mediumtests-builder-utopic-armhf/1730
        deb: http://jenkins.qa.ubuntu.com/job/generic-mediumtests-builder-utopic-armhf/1730/artifact/work/output/*zip*/output.zip
    FAILURE: http://jenkins.qa.ubuntu.com/job/mir-mediumtests-runner-mako/1794/console
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review: Needs Fixing (continuous-integration)

[Alberto Aguirre (albaguirre)]

Makes sense.

I can't think of any scenario where both read and write access is needed.

review: Approve

[PS Jenkins bot (ps-jenkins)]

FAILED: Continuous integration, rev:1700
http://jenkins.qa.ubuntu.com/job/mir-team-mir-development-branch-ci/1927/
Executed test runs:
    FAILURE: http://jenkins.qa.ubuntu.com/job/mir-android-utopic-i386-build/605/console
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-clang-utopic-amd64-build/611
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-mediumtests-utopic-touch/605
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-team-mir-development-branch-utopic-amd64-ci/448
        deb: http://jenkins.qa.ubuntu.com/job/mir-team-mir-development-branch-utopic-amd64-ci/448/artifact/work/output/*zip*/output.zip
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-team-mir-development-branch-utopic-armhf-ci/445
        deb: http://jenkins.qa.ubuntu.com/job/mir-team-mir-development-branch-utopic-armhf-ci/445/artifact/work/output/*zip*/output.zip
    SUCCESS: http://jenkins.qa.ubuntu.com/job/generic-mediumtests-builder-utopic-armhf/1790
        deb: http://jenkins.qa.ubuntu.com/job/generic-mediumtests-builder-utopic-armhf/1790/artifact/work/output/*zip*/output.zip
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    SUCCESS: http://s-jenkins.ubuntu-ci:8080/job/touch-flash-device/8608

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review: Needs Fixing (continuous-integration)

[Kevin DuBois (kdub)]

bzr: ERROR: Invalid http response for https://xmlrpc.launchpad.net/bazaar/: Unable to handle http code 502: Bad Gateway

doesnt look related

[PS Jenkins bot (ps-jenkins)]

FAILED: Continuous integration, rev:1700
http://jenkins.qa.ubuntu.com/job/mir-team-mir-development-branch-ci/1929/
Executed test runs:
    FAILURE: http://jenkins.qa.ubuntu.com/job/mir-android-utopic-i386-build/607/console
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-clang-utopic-amd64-build/613
    FAILURE: http://jenkins.qa.ubuntu.com/job/mir-mediumtests-utopic-touch/607/console
    FAILURE: http://jenkins.qa.ubuntu.com/job/mir-team-mir-development-branch-utopic-amd64-ci/450/console
    FAILURE: http://jenkins.qa.ubuntu.com/job/mir-team-mir-development-branch-utopic-armhf-ci/447/console
    FAILURE: http://jenkins.qa.ubuntu.com/job/generic-mediumtests-builder-utopic-armhf/1798/console

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review: Needs Fixing (continuous-integration)

[Alan Griffiths (alan-griffiths)]

Warning: criss-cross merge encountered. See bzr help criss-cross.
...
Text conflict in src/platform/graphics/android/android_platform.cpp
1 conflicts encountered.

review: Needs Fixing

[Cemil Azizoglu (cemil-azizoglu)]

> Makes sense.
>
> I can't think of any scenario where both read and write access is needed.

Indeed, gralloc "spec" prohibits it.

[Kevin DuBois (kdub)]

conflict addressed.

[Alan Griffiths (alan-griffiths)]

> conflict addressed.

Ack. No time to review today - abstaining to unblock

review: Abstain

[PS Jenkins bot (ps-jenkins)]

PASSED: Continuous integration, rev:1701
http://jenkins.qa.ubuntu.com/job/mir-team-mir-development-branch-ci/1935/
Executed test runs:
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-android-utopic-i386-build/617
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-clang-utopic-amd64-build/623
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-mediumtests-utopic-touch/617
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-team-mir-development-branch-utopic-amd64-ci/456
        deb: http://jenkins.qa.ubuntu.com/job/mir-team-mir-development-branch-utopic-amd64-ci/456/artifact/work/output/*zip*/output.zip
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-team-mir-development-branch-utopic-armhf-ci/453
        deb: http://jenkins.qa.ubuntu.com/job/mir-team-mir-development-branch-utopic-armhf-ci/453/artifact/work/output/*zip*/output.zip
    SUCCESS: http://jenkins.qa.ubuntu.com/job/generic-mediumtests-builder-utopic-armhf/1832
        deb: http://jenkins.qa.ubuntu.com/job/generic-mediumtests-builder-utopic-armhf/1832/artifact/work/output/*zip*/output.zip
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-mediumtests-runner-mako/1810
    SUCCESS: http://s-jenkins.ubuntu-ci:8080/job/touch-flash-device/8642

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review: Approve (continuous-integration)

[Alexandros Frantzis (afrantzis)]

Not a thorough review, but one thing that caught my eye:

TEST_F(NativeBuffer, access_for_read_while_being_read)
TEST_F(NativeBuffer, access_for_read_while_being_written)
...etc

The names describe what the arrangement and actions of the test are (while being read, try to read), but not what the expected behavior should be (does not wait). Therefore the names are not as informative as they could be. Perhaps something like:

TEST_F(NativeBuffer, does_not_wait_for_read_access_while_being_read)

[Alan Griffiths (alan-griffiths)]

> Not a thorough review, but one thing that caught my eye:
>
> TEST_F(NativeBuffer, access_for_read_while_being_read)
> TEST_F(NativeBuffer, access_for_read_while_being_written)
> ...etc
>
> The names describe what the arrangement and actions of the test are (while
> being read, try to read), but not what the expected behavior should be (does
> not wait). Therefore the names are not as informative as they could be.
> Perhaps something like:
>
> TEST_F(NativeBuffer, does_not_wait_for_read_access_while_being_read)

Agreed, arguably a "nit" better test names would aid understanding.

review: Needs Fixing

[Alexandros Frantzis (afrantzis)]

Other than the test name improvements (covered by Alan's needs fixing), looks good.

review: Approve

[PS Jenkins bot (ps-jenkins)]

PASSED: Continuous integration, rev:1702
http://jenkins.qa.ubuntu.com/job/mir-team-mir-development-branch-ci/1947/
Executed test runs:
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-android-utopic-i386-build/633
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-clang-utopic-amd64-build/639
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-mediumtests-utopic-touch/633
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-team-mir-development-branch-utopic-amd64-ci/468
        deb: http://jenkins.qa.ubuntu.com/job/mir-team-mir-development-branch-utopic-amd64-ci/468/artifact/work/output/*zip*/output.zip
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-team-mir-development-branch-utopic-armhf-ci/465
        deb: http://jenkins.qa.ubuntu.com/job/mir-team-mir-development-branch-utopic-armhf-ci/465/artifact/work/output/*zip*/output.zip
    SUCCESS: http://jenkins.qa.ubuntu.com/job/generic-mediumtests-builder-utopic-armhf/1876
        deb: http://jenkins.qa.ubuntu.com/job/generic-mediumtests-builder-utopic-armhf/1876/artifact/work/output/*zip*/output.zip
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-mediumtests-runner-mako/1824
    SUCCESS: http://s-jenkins.ubuntu-ci:8080/job/touch-flash-device/8684

Click here to trigger a rebuild:
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review: Approve (continuous-integration)

[Kevin DuBois (kdub)]

concerns addressed + approvals, so top-approving

=== modified file 'include/shared/mir/graphics/android/android_native_buffer.h'
--- include/shared/mir/graphics/android/android_native_buffer.h	2013-10-11 22:03:04 +0000
+++ include/shared/mir/graphics/android/android_native_buffer.h	2014-06-20 15:19:36 +0000
@@ -33,18 +33,21 @@
 
 struct AndroidNativeBuffer : public graphics::NativeBuffer
 {
-    AndroidNativeBuffer(std::shared_ptr<ANativeWindowBuffer> const& handle,
-        std::shared_ptr<Fence> const& fence);
+    AndroidNativeBuffer(
+        std::shared_ptr<ANativeWindowBuffer> const& handle,
+        std::shared_ptr<Fence> const& fence,
+        BufferAccess fence_access);
 
     ANativeWindowBuffer* anwb() const;
     buffer_handle_t handle() const;
     NativeFence copy_fence() const;
 
-    void wait_for_content();
-    void update_fence(NativeFence& merge_fd);
+    void ensure_available_for(BufferAccess);
+    void update_usage(NativeFence& merge_fd, BufferAccess);
 
 private:
     std::shared_ptr<Fence> fence;
+    BufferAccess access;
     std::shared_ptr<ANativeWindowBuffer> native_window_buffer;
 };
 

=== modified file 'include/shared/mir/graphics/android/native_buffer.h'
--- include/shared/mir/graphics/android/native_buffer.h	2014-03-06 06:05:17 +0000
+++ include/shared/mir/graphics/android/native_buffer.h	2014-06-20 15:19:36 +0000
@@ -27,6 +27,15 @@
 namespace graphics
 {
 
+namespace android
+{
+enum class BufferAccess
+{
+    read,
+    write
+};
+}
+
 class NativeBuffer
 {
 public:
@@ -36,8 +45,8 @@
     virtual buffer_handle_t handle() const = 0;
     virtual android::NativeFence copy_fence() const = 0;
 
-    virtual void wait_for_content() = 0;
-    virtual void update_fence(android::NativeFence& fence) = 0;
+    virtual void ensure_available_for(android::BufferAccess intent) = 0;
+    virtual void update_usage(android::NativeFence& fence, android::BufferAccess current_usage) = 0;
 
 protected:
     NativeBuffer() = default;

=== modified file 'include/test/mir_test_doubles/mock_android_native_buffer.h'
--- include/test/mir_test_doubles/mock_android_native_buffer.h	2014-03-11 13:44:57 +0000
+++ include/test/mir_test_doubles/mock_android_native_buffer.h	2014-06-20 15:19:36 +0000
@@ -54,8 +54,8 @@
     MOCK_CONST_METHOD0(handle, buffer_handle_t());
     MOCK_CONST_METHOD0(copy_fence, graphics::android::NativeFence());
 
-    MOCK_METHOD0(wait_for_content, void());
-    MOCK_METHOD1(update_fence, void(graphics::android::NativeFence&));
+    MOCK_METHOD1(ensure_available_for, void(graphics::android::BufferAccess));
+    MOCK_METHOD2(update_usage, void(graphics::android::NativeFence&, graphics::android::BufferAccess));
 
     ANativeWindowBuffer stub_anwb;
     native_handle_t native_handle;

=== modified file 'src/client/android/android_client_buffer.cpp'
--- src/client/android/android_client_buffer.cpp	2014-03-06 06:05:17 +0000
+++ src/client/android/android_client_buffer.cpp	2014-06-20 15:19:36 +0000
@@ -52,7 +52,7 @@
     anwb->usage = GRALLOC_USAGE_HW_TEXTURE | GRALLOC_USAGE_HW_RENDER;
     anwb->handle = native_handle.get();
 
-    native_window_buffer = std::make_shared<mga::AndroidNativeBuffer>(anwb, fence);
+    native_window_buffer = std::make_shared<mga::AndroidNativeBuffer>(anwb, fence, mga::BufferAccess::read);
 }
 
 mcla::AndroidClientBuffer::~AndroidClientBuffer() noexcept

=== modified file 'src/platform/graphics/android/android_alloc_adaptor.cpp'
--- src/platform/graphics/android/android_alloc_adaptor.cpp	2014-03-06 06:05:17 +0000
+++ src/platform/graphics/android/android_alloc_adaptor.cpp	2014-06-20 15:19:36 +0000
@@ -88,7 +88,7 @@
     anwb->format = format;
     anwb->usage = usage_flag;
 
-    return std::make_shared<mga::AndroidNativeBuffer>(anwb, fence);
+    return std::make_shared<mga::AndroidNativeBuffer>(anwb, fence, mga::BufferAccess::read);
 }
 
 int mga::AndroidAllocAdaptor::convert_to_android_usage(BufferUsage usage)

=== modified file 'src/platform/graphics/android/android_platform.cpp'
--- src/platform/graphics/android/android_platform.cpp	2014-06-18 22:04:55 +0000
+++ src/platform/graphics/android/android_platform.cpp	2014-06-20 15:19:36 +0000
@@ -118,7 +118,7 @@
     auto native_buffer = buffer->native_buffer_handle();
 
     /* TODO: instead of waiting, pack the fence fd in the message to the client */ 
-    native_buffer->wait_for_content();
+    native_buffer->ensure_available_for(mga::BufferAccess::write);
     if (msg_type == mg::BufferIpcMsgType::full_msg)
     {
         auto buffer_handle = native_buffer->handle();

=== modified file 'src/platform/graphics/android/buffer.cpp'
--- src/platform/graphics/android/buffer.cpp	2014-05-01 08:11:50 +0000
+++ src/platform/graphics/android/buffer.cpp	2014-06-20 15:19:36 +0000
@@ -76,7 +76,7 @@
 void mga::Buffer::gl_bind_to_texture()
 {
     std::unique_lock<std::mutex> lk(content_lock);
-    native_buffer->wait_for_content();
+    native_buffer->ensure_available_for(mga::BufferAccess::read);
 
     DispContextPair current
     {

=== modified file 'src/platform/graphics/android/fb_device.cpp'
--- src/platform/graphics/android/fb_device.cpp	2014-06-16 14:47:14 +0000
+++ src/platform/graphics/android/fb_device.cpp	2014-06-20 15:19:36 +0000
@@ -49,7 +49,7 @@
     context.swap_buffers();
     auto const& buffer = context.last_rendered_buffer();
     auto native_buffer = buffer->native_buffer_handle();
-    native_buffer->wait_for_content();
+    native_buffer->ensure_available_for(mga::BufferAccess::read);
     if (fb_device->post(fb_device.get(), native_buffer->handle()) != 0)
     {
         BOOST_THROW_EXCEPTION(std::runtime_error("error posting with fb device"));

=== modified file 'src/platform/graphics/android/hwc_fb_device.cpp'
--- src/platform/graphics/android/hwc_fb_device.cpp	2014-06-16 14:47:14 +0000
+++ src/platform/graphics/android/hwc_fb_device.cpp	2014-06-20 15:19:36 +0000
@@ -70,7 +70,7 @@
 
     auto const& buffer = context.last_rendered_buffer();
     auto native_buffer = buffer->native_buffer_handle();
-    native_buffer->wait_for_content();
+    native_buffer->ensure_available_for(mga::BufferAccess::read);
     if (fb_device->post(fb_device.get(), native_buffer->handle()) != 0)
     {
         BOOST_THROW_EXCEPTION(std::runtime_error("error posting with fb device"));

=== modified file 'src/platform/graphics/android/hwc_layers.cpp'
--- src/platform/graphics/android/hwc_layers.cpp	2014-06-18 17:12:18 +0000
+++ src/platform/graphics/android/hwc_layers.cpp	2014-06-20 15:19:36 +0000
@@ -93,7 +93,7 @@
 {
     if (hwc_layer->compositionType != HWC_FRAMEBUFFER)
     { 
-        associated_buffer->update_fence(hwc_layer->releaseFenceFd);
+        associated_buffer->update_usage(hwc_layer->releaseFenceFd, mga::BufferAccess::read);
         hwc_layer->releaseFenceFd = -1;
         hwc_layer->acquireFenceFd = -1;
         associated_buffer.reset();

=== modified file 'src/platform/graphics/android/internal_client_window.cpp'
--- src/platform/graphics/android/internal_client_window.cpp	2014-04-15 05:31:19 +0000
+++ src/platform/graphics/android/internal_client_window.cpp	2014-06-20 15:19:36 +0000
@@ -65,7 +65,7 @@
     buffer = it->second.buffer;
     lookup.erase(it);
 
-    handle->update_fence(fence_fd);
+    handle->update_usage(fence_fd, mga::BufferAccess::write);
     surface->swap_buffers(buffer);
 }
 

=== modified file 'src/platform/graphics/android/interpreter_cache.cpp'
--- src/platform/graphics/android/interpreter_cache.cpp	2014-03-06 06:05:17 +0000
+++ src/platform/graphics/android/interpreter_cache.cpp	2014-06-20 15:19:36 +0000
@@ -58,5 +58,5 @@
     }
 
     auto native_buffer = native_it->second;
-    native_buffer->update_fence(fence);
+    native_buffer->update_usage(fence, mga::BufferAccess::write);
 }

=== modified file 'src/shared/graphics/android/android_native_buffer.cpp'
--- src/shared/graphics/android/android_native_buffer.cpp	2013-10-11 23:46:05 +0000
+++ src/shared/graphics/android/android_native_buffer.cpp	2014-06-20 15:19:36 +0000
@@ -22,20 +22,26 @@
 
 mga::AndroidNativeBuffer::AndroidNativeBuffer(
     std::shared_ptr<ANativeWindowBuffer> const& anwb,
-    std::shared_ptr<Fence> const& fence)
+    std::shared_ptr<Fence> const& fence,
+    BufferAccess access)
     : fence(fence),
+      access(access),
       native_window_buffer(anwb)
 {
 }
 
-void mga::AndroidNativeBuffer::wait_for_content()
+void mga::AndroidNativeBuffer::ensure_available_for(BufferAccess intent)
 {
+    if ((access == mga::BufferAccess::read) && (intent == mga::BufferAccess::read))
+        return;
+  
     fence->wait();
 }
 
-void mga::AndroidNativeBuffer::update_fence(NativeFence& merge_fd)
+void mga::AndroidNativeBuffer::update_usage(NativeFence& merge_fd, BufferAccess updated_access)
 {
     fence->merge_with(merge_fd);
+    access = updated_access;
 }
 
 ANativeWindowBuffer* mga::AndroidNativeBuffer::anwb() const

=== modified file 'src/shared/graphics/android/mir_native_window.cpp'
--- src/shared/graphics/android/mir_native_window.cpp	2014-03-06 06:05:17 +0000
+++ src/shared/graphics/android/mir_native_window.cpp	2014-06-20 15:19:36 +0000
@@ -171,7 +171,7 @@
 {
     auto buffer = driver_interpreter->driver_requests_buffer();
     *buffer_to_driver = buffer->anwb();
-    buffer->wait_for_content();
+    buffer->ensure_available_for(mga::BufferAccess::write);
     return 0;
 }
 

=== modified file 'src/shared/testdraw/android_graphics_region_factory.cpp'
--- src/shared/testdraw/android_graphics_region_factory.cpp	2014-03-26 05:48:59 +0000
+++ src/shared/testdraw/android_graphics_region_factory.cpp	2014-06-20 15:19:36 +0000
@@ -25,6 +25,7 @@
 #include <stdexcept>
 
 namespace mtd=mir::test::draw;
+namespace mga=mir::graphics::android;
 
 namespace
 {
@@ -66,7 +67,7 @@
     std::shared_ptr<MirGraphicsRegion> graphic_region_from_handle(
         mir::graphics::NativeBuffer& native_buffer)
     {
-        native_buffer.wait_for_content();
+        native_buffer.ensure_available_for(mga::BufferAccess::write);
         auto anwb = native_buffer.anwb();
         int *vaddr;
         int usage = GRALLOC_USAGE_SW_READ_OFTEN | GRALLOC_USAGE_SW_WRITE_OFTEN;

=== modified file 'tests/unit-tests/client/android/test_android_native_window.cpp'
--- tests/unit-tests/client/android/test_android_native_window.cpp	2014-03-06 06:05:17 +0000
+++ tests/unit-tests/client/android/test_android_native_window.cpp	2014-06-20 15:19:36 +0000
@@ -182,7 +182,7 @@
     EXPECT_CALL(*mock_driver_interpreter, driver_requests_buffer())
         .Times(1)
         .WillOnce(Return(mock_buffer.get()));
-    EXPECT_CALL(*mock_buffer, wait_for_content())
+    EXPECT_CALL(*mock_buffer, ensure_available_for(mga::BufferAccess::write))
         .Times(1);
     EXPECT_CALL(*mock_buffer, copy_fence())
         .Times(0);

=== modified file 'tests/unit-tests/graphics/android/CMakeLists.txt'
--- tests/unit-tests/graphics/android/CMakeLists.txt	2014-06-02 17:07:02 +0000
+++ tests/unit-tests/graphics/android/CMakeLists.txt	2014-06-20 15:19:36 +0000
@@ -23,7 +23,7 @@
   ${CMAKE_CURRENT_SOURCE_DIR}/test_pixel_format.cpp
   ${CMAKE_CURRENT_SOURCE_DIR}/test_android_platform.cpp
   ${CMAKE_CURRENT_SOURCE_DIR}/test_interpreter_buffer_cache.cpp
-  ${CMAKE_CURRENT_SOURCE_DIR}/test_external_refcount.cpp
+  ${CMAKE_CURRENT_SOURCE_DIR}/test_native_buffer.cpp
   ${CMAKE_CURRENT_SOURCE_DIR}/test_output_builder.cpp
   ${CMAKE_CURRENT_SOURCE_DIR}/test_device_detection.cpp
   ${CMAKE_CURRENT_SOURCE_DIR}/test_hwc_wrapper.cpp

=== modified file 'tests/unit-tests/graphics/android/test_android_platform.cpp'
--- tests/unit-tests/graphics/android/test_android_platform.cpp	2014-06-16 23:37:57 +0000
+++ tests/unit-tests/graphics/android/test_android_platform.cpp	2014-06-20 15:19:36 +0000
@@ -113,7 +113,7 @@
     EXPECT_CALL(mock_packer, pack_size(_))
         .Times(1);
 
-    EXPECT_CALL(*native_buffer, wait_for_content())
+    EXPECT_CALL(*native_buffer, ensure_available_for(mga::BufferAccess::write))
         .Times(1);
 
     platform.fill_buffer_package(
@@ -137,7 +137,7 @@
         .Times(0);
 
     /* TODO: instead of waiting, pass the fd along */
-    EXPECT_CALL(*native_buffer, wait_for_content())
+    EXPECT_CALL(*native_buffer, ensure_available_for(mga::BufferAccess::write))
         .Times(1);
 
     platform.fill_buffer_package(

=== modified file 'tests/unit-tests/graphics/android/test_buffer.cpp'
--- tests/unit-tests/graphics/android/test_buffer.cpp	2014-03-06 06:05:17 +0000
+++ tests/unit-tests/graphics/android/test_buffer.cpp	2014-06-20 15:19:36 +0000
@@ -89,21 +89,21 @@
     int acquire_fake_fence_fd1 = 948;
     int acquire_fake_fence_fd2 = 954;
 
-    EXPECT_CALL(*mock_native_buffer, update_fence(acquire_fake_fence_fd1))
+    EXPECT_CALL(*mock_native_buffer, update_usage(acquire_fake_fence_fd1, mga::BufferAccess::write))
         .Times(1);
-    EXPECT_CALL(*mock_native_buffer, update_fence(acquire_fake_fence_fd2))
+    EXPECT_CALL(*mock_native_buffer, update_usage(acquire_fake_fence_fd2, mga::BufferAccess::read))
         .Times(1);
 
     mga::Buffer buffer(mock_native_buffer, extensions);
     {
         auto native_resource = buffer.native_buffer_handle();
         EXPECT_EQ(mock_native_buffer, native_resource);
-        native_resource->update_fence(acquire_fake_fence_fd1);
+        native_resource->update_usage(acquire_fake_fence_fd1, mga::BufferAccess::write);
     }
     {
         auto native_resource = buffer.native_buffer_handle();
         EXPECT_EQ(mock_native_buffer, native_resource);
-        native_resource->update_fence(acquire_fake_fence_fd2);
+        native_resource->update_usage(acquire_fake_fence_fd2, mga::BufferAccess::read);
     }
 }
 

=== modified file 'tests/unit-tests/graphics/android/test_buffer_tex_bind.cpp'
--- tests/unit-tests/graphics/android/test_buffer_tex_bind.cpp	2014-05-01 08:07:56 +0000
+++ tests/unit-tests/graphics/android/test_buffer_tex_bind.cpp	2014-06-20 15:19:36 +0000
@@ -350,7 +350,7 @@
 TEST_F(AndroidBufferBinding, gl_bind_to_texture_waits_on_fence)
 {
     using namespace testing;
-    EXPECT_CALL(*mock_native_buffer, wait_for_content())
+    EXPECT_CALL(*mock_native_buffer, ensure_available_for(mga::BufferAccess::read))
         .Times(1);
 
     mga::Buffer buffer(mock_native_buffer, extensions);

=== modified file 'tests/unit-tests/graphics/android/test_hwc_device.cpp'
--- tests/unit-tests/graphics/android/test_hwc_device.cpp	2014-06-18 15:58:27 +0000
+++ tests/unit-tests/graphics/android/test_hwc_device.cpp	2014-06-20 15:19:36 +0000
@@ -302,7 +302,7 @@
     EXPECT_CALL(*mock_hwc_device_wrapper, set(MatchesList(expected_list)))
         .InSequence(seq)
         .WillOnce(Invoke(set_fences_fn));
-    EXPECT_CALL(*mock_native_buffer, update_fence(fb_release_fence))
+    EXPECT_CALL(*mock_native_buffer, update_usage(fb_release_fence, mga::BufferAccess::read))
         .InSequence(seq);
     EXPECT_CALL(*mock_file_ops, close(hwc_retire_fence))
         .InSequence(seq);
@@ -416,11 +416,11 @@
     EXPECT_CALL(*mock_hwc_device_wrapper, set(MatchesList(expected_list)))
         .InSequence(seq)
         .WillOnce(Invoke(set_fences_fn));
-    EXPECT_CALL(*native_handle_1, update_fence(release_fence1))
-        .InSequence(seq);
-    EXPECT_CALL(*native_handle_2, update_fence(release_fence2))
-        .InSequence(seq);
-    EXPECT_CALL(*native_handle_3, update_fence(release_fence3))
+    EXPECT_CALL(*native_handle_1, update_usage(release_fence1, mga::BufferAccess::read))
+        .InSequence(seq);
+    EXPECT_CALL(*native_handle_2, update_usage(release_fence2, mga::BufferAccess::read))
+        .InSequence(seq);
+    EXPECT_CALL(*native_handle_3, update_usage(release_fence3, mga::BufferAccess::read))
         .InSequence(seq);
     
     EXPECT_TRUE(device.post_overlays(mock_context, updated_list, stub_compositor));

=== modified file 'tests/unit-tests/graphics/android/test_hwc_layers.cpp'
--- tests/unit-tests/graphics/android/test_hwc_layers.cpp	2014-06-18 15:58:27 +0000
+++ tests/unit-tests/graphics/android/test_hwc_layers.cpp	2014-06-20 15:19:36 +0000
@@ -234,7 +234,7 @@
 TEST_F(HWCLayersTest, buffer_fence_updates)
 {
     int fake_fence = 552;
-    EXPECT_CALL(*native_handle_1, update_fence(fake_fence))
+    EXPECT_CALL(*native_handle_1, update_usage(fake_fence, mga::BufferAccess::read))
         .Times(1);
     type = mga::LayerType::framebuffer_target;
     mga::HWCLayer layer(type, screen_position, alpha_enabled, list, list_index);

=== modified file 'tests/unit-tests/graphics/android/test_interpreter_buffer_cache.cpp'
--- tests/unit-tests/graphics/android/test_interpreter_buffer_cache.cpp	2014-03-06 06:05:17 +0000
+++ tests/unit-tests/graphics/android/test_interpreter_buffer_cache.cpp	2014-06-20 15:19:36 +0000
@@ -84,12 +84,12 @@
     EXPECT_EQ(use_count_before, stub_buffer1.use_count());
 }
 
-TEST_F(InterpreterResourceTest, update_fence_for)
+TEST_F(InterpreterResourceTest, update_usage_for)
 {
     int fence_fd = 44;
     mga::InterpreterCache cache;
 
-    EXPECT_CALL(*native_buffer1, update_fence(fence_fd))
+    EXPECT_CALL(*native_buffer1, update_usage(fence_fd, mga::BufferAccess::write))
         .Times(1);
 
     cache.store_buffer(stub_buffer1, native_buffer1);

=== renamed file 'tests/unit-tests/graphics/android/test_external_refcount.cpp' => 'tests/unit-tests/graphics/android/test_native_buffer.cpp'
--- tests/unit-tests/graphics/android/test_external_refcount.cpp	2014-03-06 06:05:17 +0000
+++ tests/unit-tests/graphics/android/test_native_buffer.cpp	2014-06-20 15:19:36 +0000
@@ -24,7 +24,21 @@
 namespace mtd=mir::test::doubles;
 namespace mga=mir::graphics::android;
 
-TEST(AndroidRefcount, driver_hooks)
+struct NativeBuffer : public testing::Test
+{
+    NativeBuffer() :
+        a_native_window_buffer(std::make_shared<ANativeWindowBuffer>()),
+        mock_fence(std::make_shared<testing::NiceMock<mtd::MockFence>>()),
+        fake_fd{48484}
+    {
+    }
+
+    std::shared_ptr<ANativeWindowBuffer> a_native_window_buffer;
+    std::shared_ptr<mtd::MockFence> mock_fence;
+    int fake_fd;
+};
+
+TEST_F(NativeBuffer, extends_lifetime_when_driver_calls_external_refcount_hooks)
 {
     auto native_handle_resource = std::make_shared<native_handle_t>();
     auto use_count_before = native_handle_resource.use_count();
@@ -46,7 +60,7 @@
     EXPECT_EQ(use_count_before, native_handle_resource.use_count());
 }
 
-TEST(AndroidRefcount, driver_hooks_mir_ref)
+TEST_F(NativeBuffer, is_not_destroyed_if_driver_loses_reference_while_mir_still_has_reference)
 {
     auto native_handle_resource = std::make_shared<native_handle_t>();
     auto use_count_before = native_handle_resource.use_count();
@@ -70,25 +84,56 @@
     EXPECT_EQ(use_count_before, native_handle_resource.use_count());
 }
 
-TEST(AndroidAndroidNativeBuffer, wait_for_fence)
-{
-    auto fence = std::make_shared<mtd::MockFence>();
-    EXPECT_CALL(*fence, wait())
-        .Times(1);
-
-    auto native_handle_resource = std::make_shared<ANativeWindowBuffer>();
-    mga::AndroidNativeBuffer buffer(native_handle_resource, fence);
-    buffer.wait_for_content();
-}
-
-TEST(AndroidAndroidNativeBuffer, update_fence)
-{
-    int fake_fd = 48484;
-    auto fence = std::make_shared<mtd::MockFence>();
-    EXPECT_CALL(*fence, merge_with(fake_fd))
-        .Times(1);
-
-    auto native_handle_resource = std::make_shared<ANativeWindowBuffer>();
-    mga::AndroidNativeBuffer buffer(native_handle_resource, fence);
-    buffer.update_fence(fake_fd);
+TEST_F(NativeBuffer, does_not_wait_for_read_access_while_being_read)
+{
+    EXPECT_CALL(*mock_fence, wait())
+        .Times(0);
+    mga::AndroidNativeBuffer buffer(a_native_window_buffer, mock_fence, mga::BufferAccess::read);
+    buffer.ensure_available_for(mga::BufferAccess::read);
+}
+
+TEST_F(NativeBuffer, waits_for_read_access_while_being_written)
+{
+    EXPECT_CALL(*mock_fence, wait())
+        .Times(1);
+    mga::AndroidNativeBuffer buffer(a_native_window_buffer, mock_fence, mga::BufferAccess::write);
+    buffer.ensure_available_for(mga::BufferAccess::read);
+}
+
+TEST_F(NativeBuffer, waits_for_write_access_while_being_read)
+{
+    EXPECT_CALL(*mock_fence, wait())
+        .Times(1);
+    mga::AndroidNativeBuffer buffer(a_native_window_buffer, mock_fence, mga::BufferAccess::read);
+    buffer.ensure_available_for(mga::BufferAccess::write);
+}
+
+TEST_F(NativeBuffer, waits_for_write_access_while_being_written)
+{
+    EXPECT_CALL(*mock_fence, wait())
+        .Times(1);
+    mga::AndroidNativeBuffer buffer(a_native_window_buffer, mock_fence, mga::BufferAccess::write);
+    buffer.ensure_available_for(mga::BufferAccess::write);
+}
+
+TEST_F(NativeBuffer, merges_existing_fence_with_updated_fence)
+{
+    EXPECT_CALL(*mock_fence, merge_with(fake_fd))
+        .Times(1);
+    mga::AndroidNativeBuffer buffer(a_native_window_buffer, mock_fence, mga::BufferAccess::read);
+    buffer.update_usage(fake_fd, mga::BufferAccess::write);
+}
+
+TEST_F(NativeBuffer, waits_depending_on_last_fence_update)
+{
+    EXPECT_CALL(*mock_fence, wait())
+        .Times(3);
+
+    mga::AndroidNativeBuffer buffer(a_native_window_buffer, mock_fence, mga::BufferAccess::read);
+    buffer.ensure_available_for(mga::BufferAccess::write);
+    buffer.ensure_available_for(mga::BufferAccess::read);
+
+    buffer.update_usage(fake_fd, mga::BufferAccess::write);
+    buffer.ensure_available_for(mga::BufferAccess::write);
+    buffer.ensure_available_for(mga::BufferAccess::read);
 }