[SYCL][CUDA] Expose context extended deleters on PI API

sycl/include/CL/sycl/detail/pi.def

@@ -31,6 +31,7 @@ _PI_API(piContextCreate)
 _PI_API(piContextGetInfo)
 _PI_API(piContextRetain)
 _PI_API(piContextRelease)
+_PI_API(piextContextSetExtendedDeleter)
 // Queue
 _PI_API(piQueueCreate)
 _PI_API(piQueueGetInfo)

sycl/include/CL/sycl/detail/pi.h

@@ -824,6 +824,12 @@ pi_result piContextRetain(pi_context context);
 
 pi_result piContextRelease(pi_context context);
 
+typedef void (*pi_context_extended_deleter)(void *user_data);
+
+pi_result piextContextSetExtendedDeleter(pi_context context,
+                                         pi_context_extended_deleter func,
+                                         void *user_data);
+
 //
 // Queue
 //

sycl/include/CL/sycl/detail/pi.hpp

@@ -30,6 +30,9 @@ struct trace_event_data_t;
 
 __SYCL_INLINE_NAMESPACE(cl) {
 namespace sycl {
+
+class context;
+
 namespace detail {
 
 enum class PiApiKind {
@@ -95,6 +98,10 @@ using PiMemObjectType = ::pi_mem_type;
 using PiMemImageChannelOrder = ::pi_image_channel_order;
 using PiMemImageChannelType = ::pi_image_channel_type;
 
+void contextSetExtendedDeleter(const cl::sycl::context &constext,
+                               pi_context_extended_deleter func,
+                               void *user_data);
+
 // Function to load the shared library
 // Implementation is OS dependent.
 void *loadOsLibrary(const std::string &Library);

sycl/plugins/cuda/pi_cuda.cpp

@@ -777,6 +777,12 @@ pi_result cuda_piContextRetain(pi_context context) {
   return PI_SUCCESS;
 }
 
+pi_result cuda_piextContextSetExtendedDeleter(
+    pi_context context, pi_context_extended_deleter function, void *user_data) {
+  context->set_extended_deleter(function, user_data);
+  return PI_SUCCESS;
+}
+
 /// Not applicable to CUDA, devices cannot be partitioned.
 ///
 pi_result cuda_piDevicePartition(
@@ -1462,7 +1468,7 @@ pi_result cuda_piContextRelease(pi_context ctxt) {
   if (ctxt->decrement_reference_count() > 0) {
     return PI_SUCCESS;
   }
-  ctxt->invoke_callback();
+  ctxt->invoke_extended_deleters();
 
   std::unique_ptr<_pi_context> context{ctxt};
 
@@ -3586,6 +3592,7 @@ pi_result piPluginInit(pi_plugin *PluginInit) {
   _PI_CL(piextDeviceSelectBinary, cuda_piextDeviceSelectBinary)
   _PI_CL(piextGetDeviceFunctionPointer, cuda_piextGetDeviceFunctionPointer)
   // Context
+  _PI_CL(piextContextSetExtendedDeleter, cuda_piextContextSetExtendedDeleter)
   _PI_CL(piContextCreate, cuda_piContextCreate)
   _PI_CL(piContextGetInfo, cuda_piContextGetInfo)
   _PI_CL(piContextRetain, cuda_piContextRetain)

sycl/plugins/cuda/pi_cuda.hpp

@@ -121,6 +121,14 @@ class _pi_device {
 ///  See proposal for details.
 ///
 struct _pi_context {
+
+  struct deleter_data {
+    pi_context_extended_deleter function;
+    void *user_data;
+
+    void operator()() { function(user_data); }
+  };
+
   using native_type = CUcontext;
 
   enum class kind { primary, user_defined } kind_;
@@ -138,20 +146,17 @@ struct _pi_context {
 
   ~_pi_context() { cuda_piDeviceRelease(deviceId_); }
 
-  void invoke_callback()
-  {
+  void invoke_extended_deleters() {
     std::lock_guard<std::mutex> guard(mutex_);
-    for(const auto& callback : destruction_callbacks_)
-    {
-      callback();
+    for (auto &deleter : extended_deleters_) {
+      deleter();
     }
   }
 
-  template<typename Func>
-  void register_callback(Func&& callback)
-  {
+  void set_extended_deleter(pi_context_extended_deleter function,
+                            void *user_data) {
     std::lock_guard<std::mutex> guard(mutex_);
-    destruction_callbacks_.emplace_back(std::forward<Func>(callback));
+    extended_deleters_.emplace_back(deleter_data{function, user_data});
   }
 
   pi_device get_device() const noexcept { return deviceId_; }
@@ -168,7 +173,7 @@ struct _pi_context {
 
 private:
   std::mutex mutex_;
-  std::vector<std::function<void(void)>> destruction_callbacks_;
+  std::vector<deleter_data> extended_deleters_;
 };
 
 /// PI Mem mapping to a CUDA memory allocation

sycl/source/detail/pi.cpp

@@ -11,6 +11,8 @@
 ///
 /// \ingroup sycl_pi
 
+#include "context_impl.hpp"
+#include <CL/sycl/context.hpp>
 #include <CL/sycl/detail/common.hpp>
 #include <CL/sycl/detail/pi.hpp>
 #include <detail/plugin.hpp>
@@ -53,6 +55,16 @@ namespace pi {
 
 bool XPTIInitDone = false;
 
+void contextSetExtendedDeleter(const cl::sycl::context &context,
+                               pi_context_extended_deleter func,
+                               void *user_data) {
+  auto impl = getSyclObjImpl(context);
+  auto contextHandle = reinterpret_cast<pi_context>(impl->getHandleRef());
+  auto plugin = impl->getPlugin();
+  plugin.call_nocheck<PiApiKind::piextContextSetExtendedDeleter>(
+      contextHandle, func, user_data);
+}
+
 std::string platformInfoToString(pi_platform_info info) {
   switch (info) {
   case PI_PLATFORM_INFO_PROFILE: