rusticl/context: implement clSetContextDestructorCallback

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/api/context.rs

@@ -6,6 +6,7 @@ use crate::api::icd::*;
 use crate::api::platform::*;
 use crate::api::types::*;
 use crate::api::util::*;
+use crate::cl_closure;
 use crate::core::context::*;
 
 use self::mesa_rust_util::properties::Properties;
@@ -115,3 +116,22 @@ pub fn create_context_from_type(
         user_data,
     )
 }
+
+pub fn set_context_destructor_callback(
+    context: cl_context,
+    pfn_notify: ::std::option::Option<DeleteContextCB>,
+    user_data: *mut ::std::os::raw::c_void,
+) -> CLResult<()> {
+    let c = context.get_ref()?;
+
+    // CL_INVALID_VALUE if pfn_notify is NULL.
+    if pfn_notify.is_none() {
+        return Err(CL_INVALID_VALUE);
+    }
+
+    c.dtors
+        .lock()
+        .unwrap()
+        .push(cl_closure!(|c| pfn_notify(c, user_data)));
+    Ok(())
+}

src/gallium/frontends/rusticl/api/icd.rs

@@ -170,7 +170,7 @@ pub static DISPATCH: cl_icd_dispatch = cl_icd_dispatch {
     clSetProgramSpecializationConstant: None,
     clCreateBufferWithProperties: None,
     clCreateImageWithProperties: None,
-    clSetContextDestructorCallback: None,
+    clSetContextDestructorCallback: Some(cl_set_context_destructor_callback),
 };
 
 pub type CLError = cl_int;
@@ -1503,6 +1503,16 @@ extern "C" fn cl_create_command_queue_with_properties(
     match_obj!(create_command_queue(context, device, 0), errcode_ret)
 }
 
+extern "C" fn cl_set_context_destructor_callback(
+    context: cl_context,
+    pfn_notify: ::std::option::Option<DeleteContextCB>,
+    user_data: *mut ::std::os::raw::c_void,
+) -> cl_int {
+    match_err!(set_context_destructor_callback(
+        context, pfn_notify, user_data
+    ))
+}
+
 // cl_khr_icd
 extern "C" fn cl_icd_get_platform_ids_khr(
     num_entries: cl_uint,

src/gallium/frontends/rusticl/api/types.rs

@@ -33,6 +33,13 @@ cl_callback!(
     }
 );
 
+cl_callback!(
+    DeleteContextCB {
+        context: cl_context,
+        user_data: *mut ::std::os::raw::c_void,
+    }
+);
+
 cl_callback!(
     EventCB {
         event: cl_event,

src/gallium/frontends/rusticl/core/context.rs

@@ -12,11 +12,13 @@ use std::collections::HashMap;
 use std::convert::TryInto;
 use std::os::raw::c_void;
 use std::sync::Arc;
+use std::sync::Mutex;
 
 pub struct Context {
     pub base: CLObjectBase<CL_INVALID_CONTEXT>,
     pub devs: Vec<Arc<Device>>,
     pub properties: Vec<cl_context_properties>,
+    pub dtors: Mutex<Vec<Box<dyn Fn(cl_context)>>>,
 }
 
 impl_cl_type_trait!(cl_context, Context, CL_INVALID_CONTEXT);
@@ -27,6 +29,7 @@ impl Context {
             base: CLObjectBase::new(),
             devs: devs,
             properties: properties,
+            dtors: Mutex::new(Vec::new()),
         })
     }
 
@@ -60,3 +63,15 @@ impl Context {
         Ok(res)
     }
 }
+
+impl Drop for Context {
+    fn drop(&mut self) {
+        let cl = cl_context::from_ptr(self);
+        self.dtors
+            .lock()
+            .unwrap()
+            .iter()
+            .rev()
+            .for_each(|cb| cb(cl));
+    }
+}