Make device lookup when failing

Signed-off-by: Larsen, Steffen <[email protected]>

Author: steffenlarsen

sycl/doc/extensions/experimental/sycl_ext_oneapi_inter_process_communication.asciidoc

@@ -134,14 +134,17 @@ handle_data_t get(void *ptr, const sycl::context &ctx)
 !====
 
 _Preconditions:_ `ptr` is a pointer to USM device memory on some device _D_ in
-context `ctx` and device _D_ returns `true` for
-`device::has(aspect::ext_oneapi_ipc_memory)`.
+context `ctx`. `ctx` is the same context as `ptr` was allocated against, using
+the USM device memory allocation routines.
 
 _Returns:_ An IPC "handle" to this USM memory allocation. The bytes of this
 handle can be transferred to another process on the same system, and the other
 process can use the handle to get a pointer to the same USM allocation through a
 call to the `open` function.
 
+_Throws:_ An exception with the `errc::feature_not_supported` error code if
+device _D_ does not have `aspect::ext_oneapi_ipc_memory`.
+
 !====
 a!
 [source]

sycl/source/ipc_memory.cpp

@@ -9,6 +9,7 @@
 #include <detail/adapter_impl.hpp>
 #include <detail/context_impl.hpp>
 #include <sycl/context.hpp>
+#include <sycl/usm/usm_pointer_info.hpp>
 #include <sycl/ext/oneapi/experimental/ipc_memory.hpp>
 
 namespace sycl {
@@ -19,13 +20,32 @@ __SYCL_EXPORT handle_data_t get(void *Ptr, const sycl::context &Ctx) {
   auto CtxImpl = sycl::detail::getSyclObjImpl(Ctx);
   sycl::detail::adapter_impl &Adapter = CtxImpl->getAdapter();
 
+  // If the API fails, check that the device actually supported it. We only do
+  // this if UR fails to avoid the device-lookup overhead.
+  auto CheckDeviceSupport = [Ptr, &Ctx]() {
+    sycl::device Dev = get_pointer_device(Ptr, Ctx);
+    if (!Dev.has(aspect::ext_oneapi_ipc_memory))
+      throw sycl::exception(
+          sycl::make_error_code(errc::feature_not_supported),
+          "Device does not support aspect::ext_oneapi_ipc_memory.");
+  };
+
   size_t HandleSize = 0;
-  Adapter.call<sycl::detail::UrApiKind::urIPCGetMemHandleExp>(
-      CtxImpl->getHandleRef(), Ptr, nullptr, &HandleSize);
+  auto UrRes =
+      Adapter.call_nocheck<sycl::detail::UrApiKind::urIPCGetMemHandleExp>(
+          CtxImpl->getHandleRef(), Ptr, nullptr, &HandleSize);
+  if (UrRes != UR_RESULT_SUCCESS) {
+    CheckDeviceSupport();
+    Adapter.checkUrResult(UrRes);
+  }
 
   handle_data_t Res(HandleSize);
-  Adapter.call<sycl::detail::UrApiKind::urIPCGetMemHandleExp>(
+  UrRes = Adapter.call_nocheck<sycl::detail::UrApiKind::urIPCGetMemHandleExp>(
       CtxImpl->getHandleRef(), Ptr, Res.data(), nullptr);
+  if (UrRes != UR_RESULT_SUCCESS) {
+    CheckDeviceSupport();
+    Adapter.checkUrResult(UrRes);
+  }
   return Res;
 }