[NFCI][SYCL] Stop owning platform_impl from device_impl

sycl/source/detail/device_impl.cpp

@@ -23,7 +23,7 @@ namespace detail {
 /// UR device instance.
 device_impl::device_impl(ur_device_handle_t Device, platform_impl &Platform,
                          device_impl::private_tag)
-    : MDevice(Device), MPlatform(Platform.shared_from_this()),
+    : MDevice(Device), MPlatform(Platform),
       // No need to set MRootDevice when MAlwaysRootDevice is true
       MRootDevice(Platform.MAlwaysRootDevice
                       ? nullptr
@@ -143,7 +143,7 @@ std::vector<device> device_impl::create_sub_devices(
   std::for_each(SubDevices.begin(), SubDevices.end(),
                 [&res, this](const ur_device_handle_t &a_ur_device) {
                   device sycl_device = detail::createSyclObjFromImpl<device>(
-                      MPlatform->getOrMakeDeviceImpl(a_ur_device));
+                      MPlatform.getOrMakeDeviceImpl(a_ur_device));
                   res.push_back(sycl_device);
                 });
   return res;

sycl/source/detail/device_impl.hpp

@@ -467,7 +467,7 @@ class device_impl : public std::enable_shared_from_this<device_impl> {
   platform get_platform() const;
 
   /// \return the associated adapter with this device.
-  adapter_impl &getAdapter() const { return MPlatform->getAdapter(); }
+  adapter_impl &getAdapter() const { return MPlatform.getAdapter(); }
 
   /// Check SYCL extension support by device
   ///
@@ -832,7 +832,7 @@ class device_impl : public std::enable_shared_from_this<device_impl> {
       // We claim, that all Intel FPGA devices support kernel to kernel pipe
       // feature (at least at the scope of SYCL_INTEL_data_flow_pipes
       // extension).
-      std::string platform_name = MPlatform->get_info<info::platform::name>();
+      std::string platform_name = MPlatform.get_info<info::platform::name>();
       if (platform_name == "Intel(R) FPGA Emulation Platform for OpenCL(TM)" ||
           platform_name == "Intel(R) FPGA SDK for OpenCL(TM)")
         return true;
@@ -1017,7 +1017,7 @@ class device_impl : public std::enable_shared_from_this<device_impl> {
       Result.reserve(Devs.value().size());
       for (const auto &d : Devs.value())
         Result.push_back(
-            createSyclObjFromImpl<device>(MPlatform->getOrMakeDeviceImpl(d)));
+            createSyclObjFromImpl<device>(MPlatform.getOrMakeDeviceImpl(d)));
 
       return Result;
     }
@@ -1031,7 +1031,7 @@ class device_impl : public std::enable_shared_from_this<device_impl> {
       if (ur_device_handle_t Result =
               get_info_impl<UR_DEVICE_INFO_COMPOSITE_DEVICE>())
         return createSyclObjFromImpl<device>(
-            MPlatform->getOrMakeDeviceImpl(Result));
+            MPlatform.getOrMakeDeviceImpl(Result));
 
       throw sycl::exception(make_error_code(errc::invalid),
                             "A component with aspect::ext_oneapi_is_component "
@@ -1702,10 +1702,10 @@ class device_impl : public std::enable_shared_from_this<device_impl> {
   uint64_t getCurrentDeviceTime();
 
   /// Get the backend of this device
-  backend getBackend() const { return MPlatform->getBackend(); }
+  backend getBackend() const { return MPlatform.getBackend(); }
 
   /// @brief  Get the platform impl serving this device
-  platform_impl &getPlatformImpl() const { return *MPlatform; }
+  platform_impl &getPlatformImpl() const { return MPlatform; }
 
   template <ur_device_info_t Desc>
   std::vector<info::fp_config> get_fp_config() const {
@@ -2254,7 +2254,7 @@ class device_impl : public std::enable_shared_from_this<device_impl> {
 private:
   ur_device_handle_t MDevice = 0;
   // This is used for getAdapter so should be above other properties.
-  std::shared_ptr<platform_impl> MPlatform;
+  platform_impl &MPlatform;
 
   std::shared_mutex MDeviceHostBaseTimeMutex;
   std::pair<uint64_t, uint64_t> MDeviceHostBaseTime{0, 0};

sycl/source/detail/global_handler.cpp

@@ -216,14 +216,6 @@ std::vector<std::shared_ptr<platform_impl>> &GlobalHandler::getPlatformCache() {
   return PlatformCache;
 }
 
-void GlobalHandler::clearPlatforms() {
-  if (!MPlatformCache.Inst)
-    return;
-  for (auto &PltSmartPtr : *MPlatformCache.Inst)
-    PltSmartPtr->MDevices.clear();
-  MPlatformCache.Inst->clear();
-}
-
 std::mutex &GlobalHandler::getPlatformMapMutex() {
   static std::mutex &PlatformMapMutex = getOrCreate(MPlatformMapMutex);
   return PlatformMapMutex;
@@ -392,7 +384,6 @@ void shutdown_late() {
 #endif
 
   // First, release resources, that may access adapters.
-  Handler->clearPlatforms(); // includes dropping platforms' devices ownership.
   Handler->MPlatformCache.Inst.reset(nullptr);
   Handler->MScheduler.Inst.reset(nullptr);
   Handler->MProgramManager.Inst.reset(nullptr);

sycl/source/detail/global_handler.hpp

@@ -63,8 +63,6 @@ class GlobalHandler {
   Sync &getSync();
   std::vector<std::shared_ptr<platform_impl>> &getPlatformCache();
 
-  void clearPlatforms();
-
   std::unordered_map<platform_impl *, std::shared_ptr<context_impl>> &
   getPlatformToDefaultContextCache();
 

sycl/test/gdb/printers.cpp

@@ -63,8 +63,7 @@ sycl::range<1> r(3);
 // CHECK:        32 |   backend MBackend
 
 // CHECK:         0 | class sycl::detail::device_impl
-// CHECK:        24 |   class std::shared_ptr<class sycl::detail::platform_impl> MPlatform
-// CHECK:        24 |       element_type * _M_ptr
+// CHECK:        24 |   platform_impl & MPlatform
 
 // DEVICE:        0 | class sycl::detail::AccessorImplDevice<1>
 // DEVICE:        0 |   class sycl::id<1> Offset

sycl/unittests/helpers/UrMock.hpp

@@ -613,7 +613,7 @@ template <sycl::backend Backend = backend::opencl> class UrMock {
     // This also erases each platform's devices (normally done in the library
     // shutdown) so that platforms/devices' lifetimes could work in unittests
     // scenario.
-    detail::GlobalHandler::instance().clearPlatforms();
+    detail::GlobalHandler::instance().getPlatformCache().clear();
     mock::getCallbacks().resetCallbacks();
   }