Implemented SyclQueue.submit_barrier

Author: oleksandr-pavlyk

dpctl/_backend.pxd

@@ -347,6 +347,12 @@ cdef extern from "dpctl_sycl_queue_interface.h":
         size_t Count,
         int Advice)
     cdef bool DPCTLQueue_IsInOrder(const DPCTLSyclQueueRef QRef)
+    cdef DPCTLSyclEventRef DPCTLQueue_SubmitBarrier(
+        const DPCTLSyclQueueRef QRef)
+    cdef DPCTLSyclEventRef DPCTLQueue_SubmitBarrierForEvents(
+        const DPCTLSyclQueueRef QRef,
+        const DPCTLSyclEventRef *DepEvents,
+        size_t NDepEvents)
 
 
 cdef extern from "dpctl_sycl_queue_manager.h":

dpctl/_sycl_queue.pxd

@@ -81,3 +81,4 @@ cdef public class SyclQueue (_SyclQueue) [object PySyclQueueObject, type PySyclQ
     cpdef memcpy(self, dest, src, size_t count)
     cpdef prefetch(self, ptr, size_t count=*)
     cpdef mem_advise(self, ptr, size_t count, int mem)
+    cpdef SyclEvent submit_barrier(self, dependent_events=*)

dpctl/_sycl_queue.pyx

@@ -43,6 +43,7 @@ from ._backend cimport (  # noqa: E211
     DPCTLQueue_MemAdvise,
     DPCTLQueue_Memcpy,
     DPCTLQueue_Prefetch,
+    DPCTLQueue_SubmitBarrierForEvents,
     DPCTLQueue_SubmitNDRange,
     DPCTLQueue_SubmitRange,
     DPCTLQueue_Wait,
@@ -63,6 +64,7 @@ from .enum_types import backend_type
 from cpython cimport pycapsule
 from libc.stdlib cimport free, malloc
 
+import collections.abc
 import logging
 
 __all__ = [
@@ -879,3 +881,38 @@ cdef class SyclQueue(_SyclQueue):
         return pycapsule.PyCapsule_New(
             <void *>QRef, "SyclQueueRef", &_queue_capsule_deleter
         )
+
+    cpdef SyclEvent submit_barrier(self, dependent_events=None):
+        """
+        Submits a barrier to the queue.
+        """
+        cdef DPCTLSyclEventRef *depEvents = NULL
+        cdef DPCTLSyclEventRef ERef = NULL
+        cdef size_t nDE = 0
+        # Create the array of dependent events if any
+        if (dependent_events is None or
+            (isinstance(dependent_events, collections.abc.Sequence) and
+             all([type(de) is SyclEvent for de in dependent_events]))):
+            nDE = 0 if dependent_events is None else len(dependent_events)
+        else:
+            raise TypeError(
+                "dependent_events must either None, or a sequence of "
+                ":class:`dpctl.SyclEvent` objects")
+        if nDE > 0:
+            depEvents = (
+                <DPCTLSyclEventRef*>malloc(nDE*sizeof(DPCTLSyclEventRef))
+            )
+            if not depEvents:
+                raise MemoryError()
+            else:
+                for idx, de in enumerate(dependent_events):
+                    depEvents[idx] = (<SyclEvent>de).get_event_ref()
+        ERef = DPCTLQueue_SubmitBarrierForEvents(
+            self.get_queue_ref(), depEvents, nDE)
+        free(depEvents)
+        if ERef is NULL:
+            raise SyclKernelSubmitError(
+                "Barrier submission to Sycl queue failed."
+            )
+
+        return SyclEvent._create(ERef, [])

dpctl/tests/test_sycl_queue.py

@@ -381,3 +381,16 @@ def test_hashing_of_queue():
     """
     queue_dict = {dpctl.SyclQueue(): "default_queue"}
     assert queue_dict
+
+
+def test_queue_submit_barrier(valid_filter):
+    try:
+        q = dpctl.SyclQueue(valid_filter)
+    except dpctl.SyclQueueCreationError:
+        pytest.skip("Failed to create device with supported filter")
+    ev1 = q.submit_barrier()
+    ev2 = q.submit_barrier()
+    ev3 = q.submit_barrier([ev1, ev2])
+    ev3.wait()
+    ev1.wait()
+    ev2.wait()