From afe55da595c51371ecb0bc946612f1e16b5cc45e Mon Sep 17 00:00:00 2001
From: Jonah Williams <jonahwilliams@google.com>
Date: Fri, 20 Oct 2023 17:19:24 -0700
Subject: [PATCH] [Impeller] Fix cmd pool reset from background thread.
 (flutter/engine#47184)

Make sure to clear the buffers before assigning to the recycler, as the dtor was racing with the raster thread usage.
---
 .../impeller/renderer/backend/vulkan/command_pool_vk.cc  | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/engine/src/flutter/impeller/renderer/backend/vulkan/command_pool_vk.cc b/engine/src/flutter/impeller/renderer/backend/vulkan/command_pool_vk.cc
index 9d6f70d4ee..05354271b7 100644
--- a/engine/src/flutter/impeller/renderer/backend/vulkan/command_pool_vk.cc
+++ b/engine/src/flutter/impeller/renderer/backend/vulkan/command_pool_vk.cc
@@ -40,6 +40,7 @@ class BackgroundCommandPoolVK final {
     if (!recycler) {
       return;
     }
+    buffers_.clear();
 
     recycler->Reclaim(std::move(pool_));
   }
@@ -56,8 +57,6 @@ class BackgroundCommandPoolVK final {
   std::weak_ptr<CommandPoolRecyclerVK> recycler_;
 };
 
-static bool kResetOnBackgroundThread = false;
-
 CommandPoolVK::~CommandPoolVK() {
   if (!pool_) {
     return;
@@ -75,10 +74,8 @@ CommandPoolVK::~CommandPoolVK() {
   auto reset_pool_when_dropped = BackgroundCommandPoolVK(
       std::move(pool_), std::move(collected_buffers_), recycler);
 
-  if (kResetOnBackgroundThread) {
-    UniqueResourceVKT<BackgroundCommandPoolVK> pool(
-        context->GetResourceManager(), std::move(reset_pool_when_dropped));
-  }
+  UniqueResourceVKT<BackgroundCommandPoolVK> pool(
+      context->GetResourceManager(), std::move(reset_pool_when_dropped));
 }
 
 // TODO(matanlurey): Return a status_or<> instead of {} when we have one.