[KUNLUN]Revert "revert p2p communication for xpu (#53496)" (#53633)

* Revert "revert p2p communication for xpu (#53496)"

This reverts commit eda0c58.

* update

Author: sljlp

python/paddle/distributed/fleet/meta_parallel/pp_utils/p2p_communication.py

@@ -12,7 +12,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-
 import os
 
 import numpy as np
@@ -27,10 +26,30 @@
 _use_cache = False
 _enable_partial_send_recv = True
 
+_xpu_comm_group_started = False
+
 _sync_send = os.environ.get("PADDLE_P2P_SYNC_SEND", "0")
 _sync_send = _sync_send.lower() in ['1', 'true']
 
 
+def _xpu_comm_group_start():
+    if not paddle.is_compiled_with_xpu():
+        return
+    global _xpu_comm_group_started
+    assert not _xpu_comm_group_started
+    framework.core.ProcessGroupBKCL.group_start()
+    _xpu_comm_group_started = True
+
+
+def _xpu_comm_group_end():
+    if not paddle.is_compiled_with_xpu():
+        return
+    global _xpu_comm_group_started
+    if _xpu_comm_group_started:
+        framework.core.ProcessGroupBKCL.group_end()
+        _xpu_comm_group_started = False
+
+
 def initialize_p2p_groups(hcg, use_cache=True, enable_partial_send_recv=True):
     global _hcg, _use_cache, _enable_partial_send_recv
     _hcg = hcg
@@ -357,6 +376,7 @@ def _p2p_helper(
     # TODO(Yuang Liu): use batch_isend_irecv replace all these comm ops
     tasks = []
     # start to p2p communicate
+
     if _sync_send:
         # Some devices(NPU for example) do not support asynchronized send op, So the order is
         # recv_prev -> send_next -> recv_next -> send_prev
@@ -492,8 +512,8 @@ def _p2p_helper(
                     group=_hcg.send_prev_group,
                     use_calc_stream=False,
                 )
-
     else:
+        _xpu_comm_group_start()
         if tensor_send_prev is not None:
             if isinstance(tensor_send_prev, tuple):
                 for d in tensor_send_prev:
@@ -529,6 +549,7 @@ def _p2p_helper(
                         use_calc_stream=sync_recv,
                     )
                     if sync_recv:
+                        _xpu_comm_group_end()
                         allgather_partial(
                             d,
                             nranks=mp_degree,
@@ -549,6 +570,7 @@ def _p2p_helper(
                 )
 
                 if sync_recv:
+                    _xpu_comm_group_end()
                     allgather_partial(
                         tensor_recv_prev,
                         nranks=mp_degree,
@@ -595,6 +617,7 @@ def _p2p_helper(
                     )
 
                     if sync_recv:
+                        _xpu_comm_group_end()
                         allgather_partial(
                             d,
                             nranks=mp_degree,
@@ -615,6 +638,7 @@ def _p2p_helper(
                     use_calc_stream=sync_recv,
                 )
                 if sync_recv:
+                    _xpu_comm_group_end()
                     allgather_partial(
                         tensor_recv_next,
                         nranks=mp_degree,
@@ -624,7 +648,7 @@ def _p2p_helper(
                     )
                 else:
                     tasks.append(task)
-
+        _xpu_comm_group_end()
     if not sync_recv:
         if framework.in_dygraph_mode():
             # wait irecv tasks in eager dygraph mode with new comm library