From 8326285c2dede132999de33738b18b47686fee6f Mon Sep 17 00:00:00 2001
From: Jeroen Bakker <jeroen@blender.org>
Date: Tue, 13 May 2025 13:15:46 +0200
Subject: [PATCH] Fix #138775: Vulkan: Separate discard pile for rendering

When using motion blur GPU materials and its resources can be freed when
still in use. This fix adds a workaround to store these resources
temporarily in a render discard pile. When rendering is finished (or
between frames) the resources are moved to the regular discard pile.

Pull Request: https://projects.blender.org/blender/blender/pulls/138809
---
 source/blender/gpu/vulkan/vk_backend.cc           | 13 ++++++++++++-
 source/blender/gpu/vulkan/vk_device.cc            |  1 +
 source/blender/gpu/vulkan/vk_device.hh            |  2 ++
 source/blender/gpu/vulkan/vk_device_submission.cc |  7 ++++---
 source/blender/gpu/vulkan/vk_resource_pool.cc     |  7 ++++++-
 source/blender/gpu/vulkan/vk_resource_pool.hh     |  3 ++-
 6 files changed, 27 insertions(+), 6 deletions(-)

diff --git a/source/blender/gpu/vulkan/vk_backend.cc b/source/blender/gpu/vulkan/vk_backend.cc
index b3c26a47b19..7fdb3764d85 100644
--- a/source/blender/gpu/vulkan/vk_backend.cc
+++ b/source/blender/gpu/vulkan/vk_backend.cc
@@ -592,9 +592,20 @@ void VKBackend::render_end()
       device.orphaned_data.destroy_discarded_resources(device);
     }
   }
+
+  if (BLI_thread_is_main() && !G.is_rendering) {
+    device.orphaned_data.move_data(device.orphaned_data_render,
+                                   device.orphaned_data.timeline_ + 1);
+  }
 }
 
-void VKBackend::render_step(bool /*force_resource_release*/) {}
+void VKBackend::render_step(bool force_resource_release)
+{
+  if (force_resource_release) {
+    device.orphaned_data.move_data(device.orphaned_data_render,
+                                   device.orphaned_data.timeline_ + 1);
+  }
+}
 
 void VKBackend::capabilities_init(VKDevice &device)
 {
diff --git a/source/blender/gpu/vulkan/vk_device.cc b/source/blender/gpu/vulkan/vk_device.cc
index d8aecf313cd..f6f8f1d536a 100644
--- a/source/blender/gpu/vulkan/vk_device.cc
+++ b/source/blender/gpu/vulkan/vk_device.cc
@@ -55,6 +55,7 @@ void VKDevice::deinit()
   pipelines.write_to_disk();
   pipelines.free_data();
   descriptor_set_layouts_.deinit();
+  orphaned_data_render.deinit(*this);
   orphaned_data.deinit(*this);
   vmaDestroyPool(mem_allocator_, vma_pools.external_memory);
   vmaDestroyAllocator(mem_allocator_);
diff --git a/source/blender/gpu/vulkan/vk_device.hh b/source/blender/gpu/vulkan/vk_device.hh
index f7331bfbb26..6d7150a8205 100644
--- a/source/blender/gpu/vulkan/vk_device.hh
+++ b/source/blender/gpu/vulkan/vk_device.hh
@@ -217,6 +217,8 @@ class VKDevice : public NonCopyable {
  public:
   render_graph::VKResourceStateTracker resources;
   VKDiscardPool orphaned_data;
+  /** Discard pool for resources that could still be used during rendering. */
+  VKDiscardPool orphaned_data_render;
   VKPipelinePool pipelines;
   /** Buffer to bind to unbound resource locations. */
   VKBuffer dummy_buffer;
diff --git a/source/blender/gpu/vulkan/vk_device_submission.cc b/source/blender/gpu/vulkan/vk_device_submission.cc
index fcff6b9a749..50a4bb84d29 100644
--- a/source/blender/gpu/vulkan/vk_device_submission.cc
+++ b/source/blender/gpu/vulkan/vk_device_submission.cc
@@ -60,9 +60,10 @@ TimelineValue VKDevice::render_graph_submit(render_graph::VKRenderGraph *render_
   }
   TimelineValue timeline = submit_task->timeline = submit_to_device ? ++timeline_value_ :
                                                                       timeline_value_ + 1;
-  orphaned_data.timeline_ = timeline + 1;
-  orphaned_data.move_data(context_discard_pool, timeline);
-
+  if (submit_to_device) {
+    orphaned_data.timeline_ = timeline + 1;
+    orphaned_data.move_data(context_discard_pool, timeline);
+  }
   BLI_thread_queue_push(submitted_render_graphs_, submit_task);
   submit_task = nullptr;
 
diff --git a/source/blender/gpu/vulkan/vk_resource_pool.cc b/source/blender/gpu/vulkan/vk_resource_pool.cc
index 804c2fa00f1..2bf54431a4f 100644
--- a/source/blender/gpu/vulkan/vk_resource_pool.cc
+++ b/source/blender/gpu/vulkan/vk_resource_pool.cc
@@ -173,7 +173,12 @@ VKDiscardPool &VKDiscardPool::discard_pool_get()
   }
 
   VKDevice &device = VKBackend::get().device;
-  return device.orphaned_data;
+  if (G.is_rendering) {
+    return device.orphaned_data_render;
+  }
+  else {
+    return device.orphaned_data;
+  }
 }
 
 }  // namespace blender::gpu
diff --git a/source/blender/gpu/vulkan/vk_resource_pool.hh b/source/blender/gpu/vulkan/vk_resource_pool.hh
index c786ab561b0..7da403b8594 100644
--- a/source/blender/gpu/vulkan/vk_resource_pool.hh
+++ b/source/blender/gpu/vulkan/vk_resource_pool.hh
@@ -76,6 +76,7 @@ template<typename Item> class TimelineResources : Vector<std::pair<TimelineValue
  */
 class VKDiscardPool {
   friend class VKDevice;
+  friend class VKBackend;
 
  private:
   TimelineResources<std::pair<VkImage, VmaAllocation>> images_;
@@ -123,7 +124,7 @@ class VKDiscardPool {
    * Returns the discard pool for the current thread.
    *
    * When active thread has a context it uses the context discard pool.
-   * Otherwise the device discard pool is used.
+   * Otherwise a device discard pool is used.
    */
   static VKDiscardPool &discard_pool_get();
 };