Improve interoperability between SyclDevice and DLPack devices

dpctl/_sycl_device.pyx

@@ -283,7 +283,8 @@ cdef class SyclDevice(_SyclDevice):
 
     Args:
         arg (str, optional):
-            The argument can be a selector string or ``None``.
+            The argument can be a selector string, another
+            :class:`dpctl.SyclDevice`, or ``None``.
             Defaults to ``None``.
 
     Raises:
@@ -293,9 +294,7 @@ cdef class SyclDevice(_SyclDevice):
         SyclDeviceCreationError:
             If the :class:`dpctl.SyclDevice` object creation failed.
         TypeError:
-            If the list of :class:`dpctl.SyclDevice` objects was empty,
-            or the input capsule contained a null pointer or could not
-            be renamed.
+            If the argument is not a :class:`dpctl.SyclDevice` or string.
     """
     @staticmethod
     cdef SyclDevice _create(DPCTLSyclDeviceRef dref):
@@ -363,9 +362,9 @@ cdef class SyclDevice(_SyclDevice):
                     "Could not create a SyclDevice from default selector"
                 )
         else:
-            raise ValueError(
+            raise TypeError(
                 "Invalid argument. Argument should be a str object specifying "
-                "a SYCL filter selector string."
+                "a SYCL filter selector string or another SyclDevice."
             )
 
     def print_device_info(self):
@@ -1557,7 +1556,7 @@ cdef class SyclDevice(_SyclDevice):
         cdef int i
 
         if ncounts == 0:
-            raise TypeError(
+            raise ValueError(
                 "Non-empty object representing list of counts is expected."
             )
         counts_buff = <size_t *> malloc((<size_t> ncounts) * sizeof(size_t))
@@ -1659,7 +1658,7 @@ cdef class SyclDevice(_SyclDevice):
                 Created sub-devices.
 
         Raises:
-            TypeError:
+            ValueError:
                 If the ``partition`` keyword argument is not specified or
                 the affinity domain string is not legal or is not one of the
                 three supported options.
@@ -1695,7 +1694,7 @@ cdef class SyclDevice(_SyclDevice):
                     _partition_affinity_domain_type._next_partitionable
                 )
             else:
-                raise TypeError(
+                raise ValueError(
                     "Partition affinity domain {} is not understood.".format(
                         partition
                     )
@@ -1708,11 +1707,11 @@ cdef class SyclDevice(_SyclDevice):
         else:
             try:
                 partition = int(partition)
-                return self.create_sub_devices_equally(partition)
             except Exception as e:
                 raise TypeError(
                     "Unsupported type of sub-device argument"
                 ) from e
+            return self.create_sub_devices_equally(partition)
 
     @property
     def parent_device(self):
@@ -1877,7 +1876,7 @@ cdef class SyclDevice(_SyclDevice):
                 A Python string representing a filter selector string.
 
         Raises:
-            TypeError:
+            ValueError:
                 If the device is a sub-device.
 
         :Example:
@@ -1902,7 +1901,7 @@ cdef class SyclDevice(_SyclDevice):
         else:
             # this a sub-device, free it, and raise an exception
             DPCTLDevice_Delete(pDRef)
-            raise TypeError("This SyclDevice is not a root device")
+            raise ValueError("This SyclDevice is not a root device")
 
     cdef int get_backend_and_device_type_ordinal(self):
         """ If this device is a root ``sycl::device``, returns the ordinal
@@ -1950,9 +1949,7 @@ cdef class SyclDevice(_SyclDevice):
 
     cdef int get_overall_ordinal(self):
         """ If this device is a root ``sycl::device``, returns the ordinal
-        position of this device in the vector ``sycl::device::get_devices()``
-        filtered to contain only devices with the same backend as this
-        device.
+        position of this device in the vector ``sycl::device::get_devices()``.
 
         Returns -1 if the device is a sub-device, or the device could not
         be found in the vector.
@@ -1985,9 +1982,9 @@ cdef class SyclDevice(_SyclDevice):
                 A Python string representing a filter selector string.
 
         Raises:
-            TypeError:
-                If the device is a sub-device.
             ValueError:
+                If the device is a sub-device.
+
                 If no match for the device was found in the vector
                 returned by ``sycl::device::get_devices()``
 
@@ -2026,7 +2023,7 @@ cdef class SyclDevice(_SyclDevice):
             else:
                 # this a sub-device, free it, and raise an exception
                 DPCTLDevice_Delete(pDRef)
-                raise TypeError("This SyclDevice is not a root device")
+                raise ValueError("This SyclDevice is not a root device")
         else:
             if include_backend:
                 BTy = DPCTLDevice_GetBackend(self._device_ref)
@@ -2045,6 +2042,64 @@ cdef class SyclDevice(_SyclDevice):
                 else:
                     return str(relId)
 
+    def get_unpartitioned_parent_device(self):
+        """ get_unpartitioned_parent_device()
+
+        Returns the unpartitioned parent device of this device.
+
+        If this device is already an unpartitioned, root device,
+        the same device is returned.
+
+        Returns:
+            dpctl.SyclDevice:
+                A parent, unpartitioned :class:`dpctl.SyclDevice` instance, or
+                ``self`` if already a root device.
+        """
+        cdef DPCTLSyclDeviceRef pDRef = NULL
+        cdef DPCTLSyclDeviceRef tDRef = NULL
+        pDRef = DPCTLDevice_GetParentDevice(self._device_ref)
+        if pDRef is NULL:
+            return self
+        else:
+            tDRef = DPCTLDevice_GetParentDevice(pDRef)
+            while tDRef is not NULL:
+                DPCTLDevice_Delete(pDRef)
+                pDRef = tDRef
+                tDRef = DPCTLDevice_GetParentDevice(pDRef)
+            return SyclDevice._create(pDRef)
+
+    def get_device_id(self):
+        """ get_device_id()
+        For an unpartitioned device, returns the canonical index of this device
+        in the list of devices visible to dpctl.
+
+        Returns:
+            int:
+                The index of the device.
+
+        Raises:
+            ValueError:
+                If the device could not be found.
+
+        :Example:
+            .. code-block:: python
+
+                import dpctl
+                gpu_dev = dpctl.SyclDevice("gpu")
+                i = gpu_dev.get_device_id
+                devs = dpctl.get_devices()
+                assert devs[i] == gpu_dev
+        """
+        cdef int dev_id = -1
+        cdef SyclDevice dev
+
+        dev = self.get_unpartitioned_parent_device()
+        dev_id = dev.get_overall_ordinal()
+        if dev_id < 0:
+            raise ValueError("device could not be found")
+        return dev_id
+
+
 cdef api DPCTLSyclDeviceRef SyclDevice_GetDeviceRef(SyclDevice dev):
     """
     C-API function to get opaque device reference from

dpctl/tensor/__init__.py

@@ -59,6 +59,10 @@
     uint64,
 )
 from dpctl.tensor._device import Device
+from dpctl.tensor._dldevice_conversions import (
+    dldevice_to_sycl_device,
+    sycl_device_to_dldevice,
+)
 from dpctl.tensor._dlpack import from_dlpack
 from dpctl.tensor._indexing_functions import (
     extract,
@@ -388,4 +392,6 @@
     "take_along_axis",
     "put_along_axis",
     "top_k",
+    "dldevice_to_sycl_device",
+    "sycl_device_to_dldevice",
 ]

dpctl/tensor/_dldevice_conversions.py

@@ -0,0 +1,39 @@
+#                       Data Parallel Control (dpctl)
+#
+#  Copyright 2020-2025 Intel Corporation
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+
+from .._sycl_device import SyclDevice
+from ._usmarray import DLDeviceType
+
+
+def dldevice_to_sycl_device(dl_dev: tuple):
+    if isinstance(dl_dev, tuple):
+        if len(dl_dev) != 2:
+            raise ValueError("dldevice tuple must have length 2")
+    else:
+        raise TypeError(
+            f"dl_dev is expected to be a 2-tuple, got " f"{type(dl_dev)}"
+        )
+    if dl_dev[0] != DLDeviceType.kDLOneAPI:
+        raise ValueError("dldevice type must be kDLOneAPI")
+    return SyclDevice(str(dl_dev[1]))
+
+
+def sycl_device_to_dldevice(dev: SyclDevice):
+    if not isinstance(dev, SyclDevice):
+        raise TypeError(
+            "dev is expected to be a SyclDevice, got " f"{type(dev)}"
+        )
+    return (DLDeviceType.kDLOneAPI, dev.get_device_id())

dpctl/tensor/_dlpack.pxd

@@ -47,8 +47,6 @@ cpdef object to_dlpack_versioned_capsule(usm_ndarray array, bint copied) except
 cpdef object numpy_to_dlpack_versioned_capsule(ndarray array, bint copied) except +
 cpdef object from_dlpack_capsule(object dltensor) except +
 
-cdef int get_parent_device_ordinal_id(SyclDevice dev) except *
-
 cdef class DLPackCreationError(Exception):
     """
     A DLPackCreateError exception is raised when constructing

dpctl/tensor/_dlpack.pyx

@@ -177,28 +177,6 @@ cdef object _get_default_context(c_dpctl.SyclDevice dev):
 
     return default_context
 
-
-cdef int get_parent_device_ordinal_id(c_dpctl.SyclDevice dev) except -1:
-    cdef DPCTLSyclDeviceRef pDRef = NULL
-    cdef DPCTLSyclDeviceRef tDRef = NULL
-    cdef c_dpctl.SyclDevice p_dev
-
-    pDRef = DPCTLDevice_GetParentDevice(dev.get_device_ref())
-    if pDRef is not NULL:
-        # if dev is a sub-device, find its parent
-        # and return its overall ordinal id
-        tDRef = DPCTLDevice_GetParentDevice(pDRef)
-        while tDRef is not NULL:
-            DPCTLDevice_Delete(pDRef)
-            pDRef = tDRef
-            tDRef = DPCTLDevice_GetParentDevice(pDRef)
-        p_dev = c_dpctl.SyclDevice._create(pDRef)
-        return p_dev.get_overall_ordinal()
-
-    # return overall ordinal id of argument device
-    return dev.get_overall_ordinal()
-
-
 cdef int get_array_dlpack_device_id(
     usm_ndarray usm_ary
 ) except -1:
@@ -224,14 +202,13 @@ cdef int get_array_dlpack_device_id(
                 "on non-partitioned SYCL devices on platforms where "
                 "default_context oneAPI extension is not supported."
             )
-        device_id = ary_sycl_device.get_overall_ordinal()
     else:
         if not usm_ary.sycl_context == default_context:
             raise DLPackCreationError(
                 "to_dlpack_capsule: DLPack can only export arrays based on USM "
                 "allocations bound to a default platform SYCL context"
             )
-        device_id = get_parent_device_ordinal_id(ary_sycl_device)
+    device_id = ary_sycl_device.get_device_id()
 
     if device_id < 0:
         raise DLPackCreationError(
@@ -1086,7 +1063,7 @@ def from_dlpack(x, /, *, device=None, copy=None):
                 d = device.sycl_device
             else:
                 d = device
-            dl_device = (device_OneAPI, get_parent_device_ordinal_id(<c_dpctl.SyclDevice>d))
+            dl_device = (device_OneAPI, d.get_device_id())
     if dl_device is not None:
         if (dl_device[0] not in [device_OneAPI, device_CPU]):
             raise ValueError(

dpctl/tensor/_usmarray.pyx

@@ -1304,16 +1304,16 @@ cdef class usm_ndarray:
             DLPackCreationError:
                 when the ``device_id`` could not be determined.
         """
-        cdef int dev_id = c_dlpack.get_parent_device_ordinal_id(<c_dpctl.SyclDevice>self.sycl_device)
-        if dev_id < 0:
+        try:
+            dev_id = self.sycl_device.get_device_id()
+        except ValueError as e:
             raise c_dlpack.DLPackCreationError(
                 "Could not determine id of the device where array was allocated."
             )
-        else:
-            return (
-                DLDeviceType.kDLOneAPI,
-                dev_id,
-            )
+        return (
+            DLDeviceType.kDLOneAPI,
+            dev_id,
+        )
 
     def __eq__(self, other):
         return dpctl.tensor.equal(self, other)

dpctl/tests/test_sycl_context.py

@@ -263,7 +263,7 @@ def test_cpython_api_SyclContext_Make():
 
 def test_invalid_capsule():
     cap = create_invalid_capsule()
-    with pytest.raises(ValueError):
+    with pytest.raises(TypeError):
         dpctl.SyclContext(cap)