Bump WebGL stream to high-priority on Adreno 3xx.

WebGL has performance issues on Adreno 3xx when we switch contexts
from/to the WebGL context mid-frame.

To avoid this issue, we can bump scheduler priority for the WebGL stream
to high, avoiding most mid-frame interruptions. In local testing this
(in combination with a backpressure fix) addresses known issues.

Bug: 879649, 835353
Cq-Include-Trybots: luci.chromium.try:android_optional_gpu_tests_rel;luci.chromium.try:linux_optional_gpu_tests_rel;luci.chromium.try:mac_optional_gpu_tests_rel;luci.chromium.try:win_optional_gpu_tests_rel
Change-Id: I896456b29f3b80e3e443720b9ce444e6825c1c03
Reviewed-on: https://chromium-review.googlesource.com/1200242Reviewed-by: Nasko Oskov <nasko@chromium.org>
Reviewed-by: Sunny Sachanandani <sunnyps@chromium.org>
Commit-Queue: Eric Karl <ericrk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#588287}

content/common/gpu_stream_constants.h

@@ -13,9 +13,11 @@ enum {
   kGpuStreamIdDefault,
   kGpuStreamIdWorker,
   kGpuStreamIdMedia,
+  kGpuStreamIdHighPriorityWebGL,
 };
 
-// Used for renderer compositor thread context, WebGL, canvas, etc.
+// Used for renderer compositor thread context, WebGL (when high priority is
+// not requested by workaround), canvas, etc.
 const gpu::SchedulingPriority kGpuStreamPriorityDefault =
     gpu::SchedulingPriority::kNormal;
 
@@ -31,6 +33,11 @@ const gpu::SchedulingPriority kGpuStreamPriorityMedia =
 const gpu::SchedulingPriority kGpuStreamPriorityWorker =
     gpu::SchedulingPriority::kLow;
 
+// Used for WebGL on devices where a hgih priority context is requested by the
+// |use_high_priority_for_webgl| workaround.
+const gpu::SchedulingPriority kGpuStreamPriorityHighPriorityWebGL =
+    gpu::SchedulingPriority::kHigh;
+
 }  // namespace content
 
 #endif  // CONTENT_COMMON_GPU_STREAM_CONSTANTS_H_

content/renderer/renderer_blink_platform_impl.cc

@@ -74,6 +74,7 @@
 #include "content/renderer/worker_thread_registry.h"
 #include "device/gamepad/public/cpp/gamepads.h"
 #include "gpu/command_buffer/client/gles2_interface.h"
+#include "gpu/config/gpu_driver_bug_workaround_type.h"
 #include "gpu/config/gpu_info.h"
 #include "gpu/ipc/client/gpu_channel_host.h"
 #include "media/audio/audio_output_device.h"
@@ -1050,12 +1051,19 @@ RendererBlinkPlatformImpl::CreateOffscreenGraphicsContext3DProvider(
   constexpr bool automatic_flushes = true;
   constexpr bool support_locking = false;
 
+  uint32_t stream_id = kGpuStreamIdDefault;
+  gpu::SchedulingPriority priority = kGpuStreamPriorityDefault;
+  if (gpu_channel_host->gpu_feature_info().IsWorkaroundEnabled(
+          gpu::USE_HIGH_PRIORITY_FOR_WEBGL)) {
+    stream_id = kGpuStreamIdHighPriorityWebGL;
+    priority = kGpuStreamPriorityHighPriorityWebGL;
+  }
+
   scoped_refptr<ws::ContextProviderCommandBuffer> provider(
       new ws::ContextProviderCommandBuffer(
           std::move(gpu_channel_host),
-          RenderThreadImpl::current()->GetGpuMemoryBufferManager(),
-          kGpuStreamIdDefault, kGpuStreamPriorityDefault,
-          gpu::kNullSurfaceHandle, GURL(top_document_web_url),
+          RenderThreadImpl::current()->GetGpuMemoryBufferManager(), stream_id,
+          priority, gpu::kNullSurfaceHandle, GURL(top_document_web_url),
           automatic_flushes, support_locking, web_attributes.support_grcontext,
           gpu::SharedMemoryLimits(), attributes,
           ws::command_buffer_metrics::ContextType::WEBGL));

gpu/config/gpu_driver_bug_list.json

@@ -2964,6 +2964,18 @@
       "features": [
         "disable_aimagereader"
       ]
+    },
+    {
+      "id":276,
+      "cr_bugs": [835353],
+      "description": "Adreno 3xx requires a high-priority WebGL context to avoid MSAA and performance issues",
+      "os": {
+        "type": "android"
+      },
+      "gl_renderer": "Adreno \\(TM\\) 3.*",
+      "features": [
+        "use_high_priority_for_webgl"
+      ]
     }
   ]
 }

gpu/config/gpu_workaround_list.txt

@@ -98,6 +98,7 @@ unpack_overlapping_rows_separately_unpack_buffer
 use_client_side_arrays_for_stream_buffers
 use_es2_for_oopr
 use_gpu_driver_workaround_for_testing
+use_high_priority_for_webgl
 use_intermediary_for_copy_texture_image
 use_non_zero_size_for_client_side_stream_buffers
 use_unused_standard_shared_blocks