Properly Barrier Compute Indirect Buffers (#2810)

wgpu-core/src/command/compute.rs

@@ -268,13 +268,15 @@ impl<A: HalApi> State<A> {
  Ok(())
  }
 
+ // `extra_buffer` is there to represent the indirect buffer that is also part of the usage scope.
  fn flush_states(
  &mut self,
  raw_encoder: &mut A::CommandEncoder,
  base_trackers: &mut Tracker<A>,
  bind_group_guard: &Storage<BindGroup<A>, id::BindGroupId>,
  buffer_guard: &Storage<Buffer<A>, id::BufferId>,
  texture_guard: &Storage<Texture<A>, id::TextureId>,
+ indirect_buffer: Option<id::Valid<id::BufferId>>,
  ) -> Result<(), UsageConflict> {
  for id in self.binder.list_active() {
  unsafe {
@@ -295,6 +297,13 @@ impl<A: HalApi> State<A> {
  }
  }
 
+ // Add the state of the indirect buffer if it hasn't been hit before.
+ unsafe {
+ base_trackers
+ .buffers
+ .set_and_remove_from_usage_scope_sparse(&mut self.scope.buffers, indirect_buffer);
+ }
+
  log::trace!("Encoding dispatch barriers");
 
  CommandBuffer::drain_barriers(raw_encoder, base_trackers, buffer_guard, texture_guard);
@@ -584,6 +593,7 @@ impl<G: GlobalIdentityHandlerFactory> Global<G> {
  &*bind_group_guard,
  &*buffer_guard,
  &*texture_guard,
+ None,
  )
  .map_pass_err(scope)?;
 
@@ -659,6 +669,7 @@ impl<G: GlobalIdentityHandlerFactory> Global<G> {
  &*bind_group_guard,
  &*buffer_guard,
  &*texture_guard,
+ Some(id::Valid(buffer_id)),
  )
  .map_pass_err(scope)?;
  unsafe {

wgpu-core/src/track/buffer.rs

@@ -467,8 +467,8 @@ impl<A: hub::HalApi> BufferTracker<A> {
  /// This is a really funky method used by Compute Passes to generate
  /// barriers after a call to dispatch without needing to iterate
  /// over all elements in the usage scope. We use each the
- /// bind group as a source of which IDs to look at. The bind groups
- /// must have first been added to the usage scope.
+ /// a given iterator of ids as a source of which IDs to look at.
+ /// All the IDs must have first been added to the usage scope.
  ///
  /// # Safety
  ///
@@ -477,15 +477,15 @@ impl<A: hub::HalApi> BufferTracker<A> {
  pub unsafe fn set_and_remove_from_usage_scope_sparse(
  &mut self,
  scope: &mut BufferUsageScope<A>,
- bind_group_state: &BufferBindGroupState<A>,
+ id_source: impl IntoIterator<Item = Valid<BufferId>>,
  ) {
  let incoming_size = scope.state.len();
  if incoming_size > self.start.len() {
  self.set_size(incoming_size);
  }
 
- for &(id, ref ref_count, _) in bind_group_state.buffers.iter() {
- let (index32, epoch, _) = id.0.unzip();
+ for id in id_source {
+ let (index32, _, _) = id.0.unzip();
  let index = index32 as usize;
 
  scope.debug_assert_in_bounds(index);
@@ -504,9 +504,8 @@ impl<A: hub::HalApi> BufferTracker<A> {
  state: &scope.state,
  },
  None,
- ResourceMetadataProvider::Direct {
- epoch,
- ref_count: Cow::Borrowed(ref_count),
+ ResourceMetadataProvider::Indirect {
+ metadata: &scope.metadata,
  },
  &mut self.temp,
  );

wgpu-core/src/track/mod.rs

@@ -715,7 +715,7 @@ impl<A: hub::HalApi> Tracker<A> {
  bind_group: &BindGroupStates<A>,
  ) {
  self.buffers
- .set_and_remove_from_usage_scope_sparse(&mut scope.buffers, &bind_group.buffers);
+ .set_and_remove_from_usage_scope_sparse(&mut scope.buffers, bind_group.buffers.used());
  self.textures.set_and_remove_from_usage_scope_sparse(
  textures,
  &mut scope.textures,