[vk] move framebuffer cache into CommandEncoder

This makes texture view destruction cheap since users of wgpu-hal are required to keep resources referenced by encoders alive for at least as long as the encoder is alive.

This is also a prerequisite to implement rendering to slices of 3D textures (by creating temporary texture views).

On the other hand the cache won't be as effective but that is probably ok, we can reevaluate the implementation if it turns out to be a problem.

Author: teoxoy

wgpu-hal/src/vulkan/adapter.rs

@@ -2054,7 +2054,6 @@ impl super::Adapter {
             features,
             workarounds: self.workarounds,
             render_passes: Mutex::new(Default::default()),
-            framebuffers: Mutex::new(Default::default()),
             sampler_cache: Mutex::new(super::sampler::SamplerCache::new(
                 self.private_caps.maximum_samplers,
             )),

wgpu-hal/src/vulkan/command.rs

@@ -1,9 +1,8 @@
 use super::conv;
-
 use arrayvec::ArrayVec;
 use ash::vk;
-
 use core::{mem, ops::Range};
+use hashbrown::hash_map::Entry;
 
 const ALLOCATION_GRANULARITY: u32 = 16;
 const DST_IMAGE_LAYOUT: vk::ImageLayout = vk::ImageLayout::TRANSFER_DST_OPTIMAL;
@@ -52,6 +51,26 @@ impl super::CommandEncoder {
             }
         }
     }
+
+    fn make_framebuffer(
+        &mut self,
+        key: super::FramebufferKey,
+    ) -> Result<vk::Framebuffer, crate::DeviceError> {
+        Ok(match self.framebuffers.entry(key) {
+            Entry::Occupied(e) => *e.get(),
+            Entry::Vacant(e) => {
+                let vk_info = vk::FramebufferCreateInfo::default()
+                    .render_pass(e.key().raw_pass)
+                    .width(e.key().extent.width)
+                    .height(e.key().extent.height)
+                    .layers(e.key().extent.depth_or_array_layers)
+                    .attachments(&e.key().attachments);
+
+                let raw = unsafe { self.device.raw.create_framebuffer(&vk_info, None).unwrap() };
+                *e.insert(raw)
+            }
+        })
+    }
 }
 
 impl crate::CommandEncoder for super::CommandEncoder {
@@ -796,7 +815,7 @@ impl crate::CommandEncoder for super::CommandEncoder {
 
         let raw_pass = self.device.make_render_pass(rp_key).unwrap();
         fb_key.raw_pass = raw_pass;
-        let raw_framebuffer = self.device.make_framebuffer(fb_key).unwrap();
+        let raw_framebuffer = self.make_framebuffer(fb_key).unwrap();
 
         let vk_info = vk::RenderPassBeginInfo::default()
             .render_pass(raw_pass)

wgpu-hal/src/vulkan/device.rs

@@ -202,26 +202,6 @@ impl super::DeviceShared {
         })
     }
 
-    pub fn make_framebuffer(
-        &self,
-        key: super::FramebufferKey,
-    ) -> Result<vk::Framebuffer, crate::DeviceError> {
-        Ok(match self.framebuffers.lock().entry(key) {
-            Entry::Occupied(e) => *e.get(),
-            Entry::Vacant(e) => {
-                let vk_info = vk::FramebufferCreateInfo::default()
-                    .render_pass(e.key().raw_pass)
-                    .width(e.key().extent.width)
-                    .height(e.key().extent.height)
-                    .layers(e.key().extent.depth_or_array_layers)
-                    .attachments(&e.key().attachments);
-
-                let raw = unsafe { self.raw.create_framebuffer(&vk_info, None).unwrap() };
-                *e.insert(raw)
-            }
-        })
-    }
-
     fn make_memory_ranges<'a, I: 'a + Iterator<Item = crate::MemoryRange>>(
         &self,
         buffer: &'a super::Buffer,
@@ -1312,15 +1292,6 @@ impl crate::Device for super::Device {
         })
     }
     unsafe fn destroy_texture_view(&self, view: super::TextureView) {
-        {
-            let mut fbuf_lock = self.shared.framebuffers.lock();
-            for (key, &raw_fbuf) in fbuf_lock.iter() {
-                if key.attachments.iter().any(|at_view| *at_view == view.raw) {
-                    unsafe { self.shared.raw.destroy_framebuffer(raw_fbuf, None) };
-                }
-            }
-            fbuf_lock.retain(|key, _| !key.attachments.iter().any(|at_view| *at_view == view.raw));
-        }
         unsafe { self.shared.raw.destroy_image_view(view.raw, None) };
 
         self.counters.texture_views.sub(1);
@@ -1413,6 +1384,7 @@ impl crate::Device for super::Device {
             discarded: Vec::new(),
             rpass_debug_marker_active: false,
             end_of_pass_timer_query: None,
+            framebuffers: Default::default(),
             counters: Arc::clone(&self.counters),
         })
     }

wgpu-hal/src/vulkan/mod.rs

@@ -602,13 +602,6 @@ struct RenderPassKey {
     multiview: Option<NonZeroU32>,
 }
 
-#[derive(Clone, Eq, Hash, PartialEq)]
-struct FramebufferKey {
-    raw_pass: vk::RenderPass,
-    attachments: ArrayVec<vk::ImageView, { MAX_TOTAL_ATTACHMENTS }>,
-    extent: wgt::Extent3d,
-}
-
 struct DeviceShared {
     raw: ash::Device,
     family_index: u32,
@@ -626,7 +619,6 @@ struct DeviceShared {
     workarounds: Workarounds,
     features: wgt::Features,
     render_passes: Mutex<FastHashMap<RenderPassKey, vk::RenderPass>>,
-    framebuffers: Mutex<FastHashMap<FramebufferKey, vk::Framebuffer>>,
     sampler_cache: Mutex<sampler::SamplerCache>,
     memory_allocations_counter: InternalCounter,
 }
@@ -636,9 +628,6 @@ impl Drop for DeviceShared {
         for &raw in self.render_passes.lock().values() {
             unsafe { self.raw.destroy_render_pass(raw, None) };
         }
-        for &raw in self.framebuffers.lock().values() {
-            unsafe { self.raw.destroy_framebuffer(raw, None) };
-        }
         if self.drop_guard.is_none() {
             unsafe { self.raw.destroy_device(None) };
         }
@@ -874,6 +863,13 @@ impl Temp {
     }
 }
 
+#[derive(Clone, Eq, Hash, PartialEq)]
+struct FramebufferKey {
+    raw_pass: vk::RenderPass,
+    attachments: ArrayVec<vk::ImageView, { MAX_TOTAL_ATTACHMENTS }>,
+    extent: wgt::Extent3d,
+}
+
 pub struct CommandEncoder {
     raw: vk::CommandPool,
     device: Arc<DeviceShared>,
@@ -910,6 +906,8 @@ pub struct CommandEncoder {
     /// the given pool & location.
     end_of_pass_timer_query: Option<(vk::QueryPool, u32)>,
 
+    framebuffers: FastHashMap<FramebufferKey, vk::Framebuffer>,
+
     counters: Arc<wgt::HalCounters>,
 }
 
@@ -931,6 +929,11 @@ impl Drop for CommandEncoder {
             // fields.
             self.device.raw.destroy_command_pool(self.raw, None);
         }
+
+        for (_, fb) in self.framebuffers.drain() {
+            unsafe { self.device.raw.destroy_framebuffer(fb, None) };
+        }
+
         self.counters.command_encoders.sub(1);
     }
 }