rusticl/mesa: add fencing support

Signed-off-by: Karol Herbst <kherbst@redhat.com>
Acked-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/15439>

src/gallium/frontends/rusticl/mesa/pipe/context.rs

@@ -1,7 +1,9 @@
 extern crate mesa_rust_gen;
 
 use crate::compiler::nir::*;
+use crate::pipe::fence::*;
 use crate::pipe::resource::*;
+use crate::pipe::screen::*;
 use crate::pipe::transfer::*;
 
 use self::mesa_rust_gen::*;
@@ -13,15 +15,17 @@ use std::sync::Arc;
 
 pub struct PipeContext {
     pipe: NonNull<pipe_context>,
+    screen: Arc<PipeScreen>,
 }
 
 unsafe impl Send for PipeContext {}
 unsafe impl Sync for PipeContext {}
 
 impl PipeContext {
-    pub(super) fn new(context: *mut pipe_context) -> Option<Arc<Self>> {
+    pub(super) fn new(context: *mut pipe_context, screen: &Arc<PipeScreen>) -> Option<Arc<Self>> {
         let s = Self {
             pipe: NonNull::new(context)?,
+            screen: screen.clone(),
         };
 
         if !has_required_cbs(unsafe { s.pipe.as_ref() }) {
@@ -176,6 +180,14 @@ impl PipeContext {
     pub fn memory_barrier(&self, barriers: u32) {
         unsafe { self.pipe.as_ref().memory_barrier.unwrap()(self.pipe.as_ptr(), barriers) }
     }
+
+    pub fn flush(&self) -> PipeFence {
+        unsafe {
+            let mut fence = ptr::null_mut();
+            self.pipe.as_ref().flush.unwrap()(self.pipe.as_ptr(), &mut fence, 0);
+            PipeFence::new(fence, &self.screen)
+        }
+    }
 }
 
 impl Drop for PipeContext {
@@ -195,6 +207,7 @@ fn has_required_cbs(c: &pipe_context) -> bool {
         && c.buffer_unmap.is_some()
         && c.create_compute_state.is_some()
         && c.delete_compute_state.is_some()
+        && c.flush.is_some()
         && c.launch_grid.is_some()
         && c.memory_barrier.is_some()
         && c.set_global_binding.is_some()

src/gallium/frontends/rusticl/mesa/pipe/fence.rs

@@ -0,0 +1,31 @@
+extern crate mesa_rust_gen;
+
+use crate::pipe::screen::*;
+
+use self::mesa_rust_gen::*;
+
+use std::sync::Arc;
+
+pub struct PipeFence {
+    fence: *mut pipe_fence_handle,
+    screen: Arc<PipeScreen>,
+}
+
+impl PipeFence {
+    pub fn new(fence: *mut pipe_fence_handle, screen: &Arc<PipeScreen>) -> Self {
+        Self {
+            fence: fence,
+            screen: screen.clone(),
+        }
+    }
+
+    pub fn wait(&self) {
+        self.screen.fence_finish(self.fence);
+    }
+}
+
+impl Drop for PipeFence {
+    fn drop(&mut self) {
+        self.screen.unref_fence(self.fence);
+    }
+}

src/gallium/frontends/rusticl/mesa/pipe/mod.rs

@@ -1,5 +1,6 @@
 pub mod context;
 pub mod device;
+pub mod fence;
 pub mod resource;
 pub mod screen;
 pub mod transfer;

src/gallium/frontends/rusticl/mesa/pipe/screen.rs

@@ -71,13 +71,16 @@ impl PipeScreen {
     }
 
     pub fn create_context(self: &Arc<Self>) -> Option<Arc<PipeContext>> {
-        PipeContext::new(unsafe {
-            (*self.screen).context_create.unwrap()(
-                self.screen,
-                ptr::null_mut(),
-                PIPE_CONTEXT_COMPUTE_ONLY,
-            )
-        })
+        PipeContext::new(
+            unsafe {
+                (*self.screen).context_create.unwrap()(
+                    self.screen,
+                    ptr::null_mut(),
+                    PIPE_CONTEXT_COMPUTE_ONLY,
+                )
+            },
+            self,
+        )
     }
 
     pub fn resource_create_buffer(&self, size: u32) -> Option<PipeResource> {
@@ -185,6 +188,20 @@ impl PipeScreen {
             }
         }
     }
+
+    pub(super) fn unref_fence(&self, mut fence: *mut pipe_fence_handle) {
+        unsafe {
+            let s = &mut *self.screen;
+            s.fence_reference.unwrap()(s, &mut fence, ptr::null_mut());
+        }
+    }
+
+    pub(super) fn fence_finish(&self, fence: *mut pipe_fence_handle) {
+        unsafe {
+            let s = &mut *self.screen;
+            s.fence_finish.unwrap()(s, ptr::null_mut(), fence, PIPE_TIMEOUT_INFINITE as u64);
+        }
+    }
 }
 
 impl Drop for PipeScreen {
@@ -199,6 +216,8 @@ fn has_required_cbs(screen: *mut pipe_screen) -> bool {
     let s = unsafe { *screen };
     s.context_create.is_some()
         && s.destroy.is_some()
+        && s.fence_finish.is_some()
+        && s.fence_reference.is_some()
         && s.get_compiler_options.is_some()
         && s.get_compute_param.is_some()
         && s.get_name.is_some()

src/gallium/frontends/rusticl/meson.build

@@ -36,6 +36,7 @@ libmesa_rust_files = files(
   'mesa/compiler/clc/spirv.rs',
   'mesa/pipe/context.rs',
   'mesa/pipe/device.rs',
+  'mesa/pipe/fence.rs',
   'mesa/pipe/mod.rs',
   'mesa/pipe/screen.rs',
   'mesa/pipe/transfer.rs',