Split the tracker into stateful/stateless to reduce the overhead

wgpu-core/src/command/bundle.rs

@@ -214,7 +214,7 @@ impl RenderBundleEncoder {
                     state.set_bind_group(index, bind_group_id, bind_group.layout_id, offsets);
                     state
                         .trackers
-                        .merge_extend(&bind_group.used)
+                        .merge_extend_all(&bind_group.used)
                         .map_pass_err(scope)?;
                 }
                 RenderCommand::SetPipeline(pipeline_id) => {

wgpu-core/src/command/compute.rs

@@ -12,7 +12,7 @@ use crate::{
     id,
     memory_init_tracker::{MemoryInitKind, MemoryInitTrackerAction},
     resource::{Buffer, BufferUse, Texture},
-    track::{TrackerSet, UsageConflict},
+    track::{StatefulTrackerSubset, TrackerSet, UsageConflict},
     validation::{check_buffer_usage, MissingBufferUsageError},
     Label, DOWNLEVEL_ERROR_WARNING_MESSAGE,
 };
@@ -193,7 +193,7 @@ where
 struct State {
     binder: Binder,
     pipeline: StateChange<id::ComputePipelineId>,
-    trackers: TrackerSet,
+    trackers: StatefulTrackerSubset,
     debug_scope_depth: u32,
 }
 
@@ -223,6 +223,7 @@ impl State {
     ) -> Result<(), UsageConflict> {
         for id in self.binder.list_active() {
             self.trackers.merge_extend(&bind_group_guard[id].used)?;
+            base_trackers.merge_extend_stateless(&bind_group_guard[id].used);
         }
 
         log::trace!("Encoding dispatch barriers");
@@ -230,7 +231,8 @@ impl State {
         CommandBuffer::insert_barriers(
             raw_cmd_buf,
             base_trackers,
-            &self.trackers,
+            &self.trackers.buffers,
+            &self.trackers.textures,
             buffer_guard,
             texture_guard,
         );
@@ -303,7 +305,7 @@ impl<G: GlobalIdentityHandlerFactory> Global<G> {
         let mut state = State {
             binder: Binder::new(),
             pipeline: StateChange::new(),
-            trackers: TrackerSet::new(B::VARIANT),
+            trackers: StatefulTrackerSubset::new(B::VARIANT),
             debug_scope_depth: 0,
         };
         let mut temp_offsets = Vec::new();

wgpu-core/src/command/mod.rs

@@ -27,7 +27,7 @@ use crate::{
     id,
     memory_init_tracker::MemoryInitTrackerAction,
     resource::{Buffer, Texture},
-    track::TrackerSet,
+    track::{BufferState, ResourceTracker, TextureState, TrackerSet},
     Label, PrivateFeatures, Stored,
 };
 
@@ -74,7 +74,8 @@ impl<B: GfxBackend> CommandBuffer<B> {
     pub(crate) fn insert_barriers(
         raw: &mut B::CommandBuffer,
         base: &mut TrackerSet,
-        head: &TrackerSet,
+        head_buffers: &ResourceTracker<BufferState>,
+        head_textures: &ResourceTracker<TextureState>,
         buffer_guard: &Storage<Buffer<B>, id::BufferId>,
         texture_guard: &Storage<Texture<B>, id::TextureId>,
     ) {
@@ -82,25 +83,17 @@ impl<B: GfxBackend> CommandBuffer<B> {
 
         profiling::scope!("insert_barriers");
         debug_assert_eq!(B::VARIANT, base.backend());
-        debug_assert_eq!(B::VARIANT, head.backend());
 
-        let buffer_barriers = base.buffers.merge_replace(&head.buffers).map(|pending| {
+        let buffer_barriers = base.buffers.merge_replace(head_buffers).map(|pending| {
             let buf = &buffer_guard[pending.id];
             pending.into_hal(buf)
         });
-        let texture_barriers = base.textures.merge_replace(&head.textures).map(|pending| {
+        let texture_barriers = base.textures.merge_replace(head_textures).map(|pending| {
             let tex = &texture_guard[pending.id];
             pending.into_hal(tex)
         });
-        base.views.merge_extend(&head.views).unwrap();
-        base.bind_groups.merge_extend(&head.bind_groups).unwrap();
-        base.samplers.merge_extend(&head.samplers).unwrap();
-        base.compute_pipes
-            .merge_extend(&head.compute_pipes)
-            .unwrap();
-        base.render_pipes.merge_extend(&head.render_pipes).unwrap();
-        base.bundles.merge_extend(&head.bundles).unwrap();
 
+        //TODO: be more deliberate about the stages
         let stages = all_buffer_stages() | all_image_stages();
         unsafe {
             raw.pipeline_barrier(

wgpu-core/src/command/render.rs

@@ -19,7 +19,7 @@ use crate::{
     memory_init_tracker::{MemoryInitKind, MemoryInitTrackerAction},
     pipeline::PipelineFlags,
     resource::{BufferUse, Texture, TextureUse, TextureView, TextureViewInner},
-    track::{TextureSelector, TrackerSet, UsageConflict},
+    track::{StatefulTrackerSubset, TextureSelector, UsageConflict},
     validation::{
         check_buffer_usage, check_texture_usage, MissingBufferUsageError, MissingTextureUsageError,
     },
@@ -504,7 +504,7 @@ struct RenderAttachment<'a> {
 
 struct RenderPassInfo<'a, B: hal::Backend> {
     context: RenderPassContext,
-    trackers: TrackerSet,
+    trackers: StatefulTrackerSubset,
     render_attachments: AttachmentDataVec<RenderAttachment<'a>>,
     used_swap_chain: Option<Stored<id::SwapChainId>>,
     is_ds_read_only: bool,
@@ -517,7 +517,7 @@ impl<'a, B: GfxBackend> RenderPassInfo<'a, B> {
         raw: &mut B::CommandBuffer,
         color_attachments: &[RenderPassColorAttachment],
         depth_stencil_attachment: Option<&RenderPassDepthStencilAttachment>,
-        cmd_buf: &CommandBuffer<B>,
+        cmd_buf: &mut CommandBuffer<B>,
         device: &Device<B>,
         view_guard: &'a Storage<TextureView<B>, id::TextureViewId>,
     ) -> Result<Self, RenderPassErrorInner> {
@@ -536,7 +536,6 @@ impl<'a, B: GfxBackend> RenderPassInfo<'a, B> {
         let mut sample_count = 0;
         let mut depth_stencil_aspects = hal::format::Aspects::empty();
         let mut used_swap_chain = None::<Stored<id::SwapChainId>>;
-        let mut trackers = TrackerSet::new(B::VARIANT);
 
         let mut add_view = |view: &TextureView<B>, type_name| {
             if let Some(ex) = extent {
@@ -564,7 +563,8 @@ impl<'a, B: GfxBackend> RenderPassInfo<'a, B> {
         let rp_key = {
             let depth_stencil = match depth_stencil_attachment {
                 Some(at) => {
-                    let view = trackers
+                    let view = cmd_buf
+                        .trackers
                         .views
                         .use_extend(&*view_guard, at.view, (), ())
                         .map_err(|_| RenderPassErrorInner::InvalidAttachment(at.view))?;
@@ -627,7 +627,8 @@ impl<'a, B: GfxBackend> RenderPassInfo<'a, B> {
             let mut resolves = ArrayVec::new();
 
             for at in color_attachments {
-                let view = trackers
+                let view = cmd_buf
+                    .trackers
                     .views
                     .use_extend(&*view_guard, at.view, (), ())
                     .map_err(|_| RenderPassErrorInner::InvalidAttachment(at.view))?;
@@ -690,7 +691,8 @@ impl<'a, B: GfxBackend> RenderPassInfo<'a, B> {
             }
 
             for resolve_target in color_attachments.iter().flat_map(|at| at.resolve_target) {
-                let view = trackers
+                let view = cmd_buf
+                    .trackers
                     .views
                     .use_extend(&*view_guard, resolve_target, (), ())
                     .map_err(|_| RenderPassErrorInner::InvalidAttachment(resolve_target))?;
@@ -961,7 +963,7 @@ impl<'a, B: GfxBackend> RenderPassInfo<'a, B> {
 
         Ok(Self {
             context,
-            trackers,
+            trackers: StatefulTrackerSubset::new(B::VARIANT),
             render_attachments,
             used_swap_chain,
             is_ds_read_only,
@@ -973,7 +975,8 @@ impl<'a, B: GfxBackend> RenderPassInfo<'a, B> {
     fn finish(
         mut self,
         texture_guard: &Storage<Texture<B>, id::TextureId>,
-    ) -> Result<(TrackerSet, Option<Stored<id::SwapChainId>>), RenderPassErrorInner> {
+    ) -> Result<(StatefulTrackerSubset, Option<Stored<id::SwapChainId>>), RenderPassErrorInner>
+    {
         profiling::scope!("finish", "RenderPassInfo");
 
         for ra in self.render_attachments {
@@ -1122,7 +1125,7 @@ impl<G: GlobalIdentityHandlerFactory> Global<G> {
                         );
                         dynamic_offset_count += num_dynamic_offsets as usize;
 
-                        let bind_group = info
+                        let bind_group = cmd_buf
                             .trackers
                             .bind_groups
                             .use_extend(&*bind_group_guard, bind_group_id, (), ())
@@ -1132,9 +1135,11 @@ impl<G: GlobalIdentityHandlerFactory> Global<G> {
                             .validate_dynamic_bindings(&temp_offsets)
                             .map_pass_err(scope)?;
 
+                        // merge the resource tracker in
                         info.trackers
                             .merge_extend(&bind_group.used)
                             .map_pass_err(scope)?;
+                        cmd_buf.trackers.merge_extend_stateless(&bind_group.used);
 
                         cmd_buf.buffer_memory_init_actions.extend(
                             bind_group.used_buffer_ranges.iter().filter_map(|action| {
@@ -1184,7 +1189,7 @@ impl<G: GlobalIdentityHandlerFactory> Global<G> {
                             continue;
                         }
 
-                        let pipeline = info
+                        let pipeline = cmd_buf
                             .trackers
                             .render_pipes
                             .use_extend(&*pipeline_guard, pipeline_id, (), ())
@@ -1826,7 +1831,7 @@ impl<G: GlobalIdentityHandlerFactory> Global<G> {
                     } => {
                         let scope = PassErrorScope::WriteTimestamp;
 
-                        let query_set = info
+                        let query_set = cmd_buf
                             .trackers
                             .query_sets
                             .use_extend(&*query_set_guard, query_set_id, (), ())
@@ -1853,7 +1858,7 @@ impl<G: GlobalIdentityHandlerFactory> Global<G> {
                     } => {
                         let scope = PassErrorScope::BeginPipelineStatisticsQuery;
 
-                        let query_set = info
+                        let query_set = cmd_buf
                             .trackers
                             .query_sets
                             .use_extend(&*query_set_guard, query_set_id, (), ())
@@ -1887,7 +1892,7 @@ impl<G: GlobalIdentityHandlerFactory> Global<G> {
                     }
                     RenderCommand::ExecuteBundle(bundle_id) => {
                         let scope = PassErrorScope::ExecuteBundle;
-                        let bundle = info
+                        let bundle = cmd_buf
                             .trackers
                             .bundles
                             .use_extend(&*bundle_guard, bundle_id, (), ())
@@ -1984,7 +1989,8 @@ impl<G: GlobalIdentityHandlerFactory> Global<G> {
         super::CommandBuffer::insert_barriers(
             last_cmd_buf,
             &mut cmd_buf.trackers,
-            &trackers,
+            &trackers.buffers,
+            &trackers.textures,
             &*buffer_guard,
             &*texture_guard,
         );

wgpu-core/src/device/queue.rs

@@ -760,10 +760,12 @@ impl<G: GlobalIdentityHandlerFactory> Global<G> {
                                 .begin_primary(hal::command::CommandBufferFlags::ONE_TIME_SUBMIT);
                         }
                         log::trace!("Stitching command buffer {:?} before submission", cmb_id);
+                        trackers.merge_extend_stateless(&cmdbuf.trackers);
                         CommandBuffer::insert_barriers(
                             &mut transit,
                             &mut *trackers,
-                            &cmdbuf.trackers,
+                            &cmdbuf.trackers.buffers,
+                            &cmdbuf.trackers.textures,
                             &*buffer_guard,
                             &*texture_guard,
                         );

wgpu-core/src/track/mod.rs

@@ -625,10 +625,17 @@ impl TrackerSet {
     }
 
     /// Merge all the trackers of another instance by extending
-    /// the usage. Panics on a conflict.
-    pub fn merge_extend(&mut self, other: &Self) -> Result<(), UsageConflict> {
+    /// the usage. Panics on a stateless conflict, returns a conflict otherwise.
+    pub fn merge_extend_all(&mut self, other: &Self) -> Result<(), UsageConflict> {
         self.buffers.merge_extend(&other.buffers)?;
         self.textures.merge_extend(&other.textures)?;
+        self.merge_extend_stateless(other);
+        Ok(())
+    }
+
+    /// Merge all the stateless trackers of another instance by extending
+    /// the usage. Panics on a conflict.
+    pub fn merge_extend_stateless(&mut self, other: &Self) {
         self.views.merge_extend(&other.views).unwrap();
         self.bind_groups.merge_extend(&other.bind_groups).unwrap();
         self.samplers.merge_extend(&other.samplers).unwrap();
@@ -638,10 +645,38 @@ impl TrackerSet {
         self.render_pipes.merge_extend(&other.render_pipes).unwrap();
         self.bundles.merge_extend(&other.bundles).unwrap();
         self.query_sets.merge_extend(&other.query_sets).unwrap();
-        Ok(())
     }
 
     pub fn backend(&self) -> wgt::Backend {
         self.buffers.backend
     }
 }
+
+#[derive(Debug)]
+pub(crate) struct StatefulTrackerSubset {
+    pub buffers: ResourceTracker<BufferState>,
+    pub textures: ResourceTracker<TextureState>,
+}
+
+impl StatefulTrackerSubset {
+    /// Create an empty set.
+    pub fn new(backend: wgt::Backend) -> Self {
+        Self {
+            buffers: ResourceTracker::new(backend),
+            textures: ResourceTracker::new(backend),
+        }
+    }
+
+    /// Clear all the trackers.
+    pub fn clear(&mut self) {
+        self.buffers.clear();
+        self.textures.clear();
+    }
+
+    /// Merge all the trackers of another tracker the usage.
+    pub fn merge_extend(&mut self, other: &TrackerSet) -> Result<(), UsageConflict> {
+        self.buffers.merge_extend(&other.buffers)?;
+        self.textures.merge_extend(&other.textures)?;
+        Ok(())
+    }
+}