[KVPool][BugFix] Correctly initialize head_or_tp_rank for mooncake backend (#6498)

### What this PR does / why we need it?
The problem that the local priority is not used in the A2 environment on
the Mooncake node is resolved.

- vLLM version: v0.15.0
- vLLM main: https://github.com/vllm-project/vllm/commit/v0.15.0

---------

Signed-off-by: 房建伟 <fangjianwei@fangjianweideMacBook-Air.local>
Co-authored-by: Pz1116 <zpbzpb123123@gmail.com>

vllm_ascend/distributed/kv_transfer/kv_pool/ascend_store/backend/mooncake_backend.py

@@ -14,6 +14,7 @@ from vllm.utils.network_utils import get_ip
 
 from vllm_ascend.distributed.kv_transfer.kv_pool.ascend_store.backend.backend import Backend
 from vllm_ascend.distributed.kv_transfer.utils.mooncake_transfer_engine import global_te
+from vllm_ascend.utils import AscendDeviceType, get_ascend_device_type
 
 DEFAULT_GLOBAL_SEGMENT_SIZE = 3355443200  # 3.125 GiB
 DEFAULT_LOCAL_BUFFER_SIZE = 1073741824  # 1.0 GiB
@@ -63,6 +64,10 @@ class MooncakeBackend(Backend):
 
     def put(self, keys: list[str], addrs: list[list[int]], sizes: list[list[int]]):
         try:
+            soc_version = get_ascend_device_type()
+            if soc_version in {AscendDeviceType.A2}:
+                res = self.store.batch_put_from_multi_buffers(keys, addrs, sizes)
+            else:
                 config = ReplicateConfig()
                 config.preferred_segment = self.local_seg
                 config.prefer_alloc_in_same_node = True
@@ -75,6 +80,10 @@ class MooncakeBackend(Backend):
 
     def get(self, keys: list[str], addrs: list[list[int]], sizes: list[list[int]]):
         try:
+            soc_version = get_ascend_device_type()
+            if soc_version in {AscendDeviceType.A2}:
+                res = self.store.batch_get_into_multi_buffers(keys, addrs, sizes)
+            else:
                 res = self.store.batch_get_into_multi_buffers(keys, addrs, sizes, True)
             for value in res:
                 if value < 0:

vllm_ascend/distributed/kv_transfer/kv_pool/ascend_store/pool_worker.py

@@ -30,6 +30,7 @@ from vllm_ascend.distributed.kv_transfer.kv_pool.ascend_store.kv_transfer import
     KVCacheStoreSendingThread,
     KVTransferThread,
 )
+from vllm_ascend.utils import AscendDeviceType, get_ascend_device_type
 
 backend_map = {
     "mooncake": {
@@ -97,6 +98,12 @@ class KVPoolWorker:
             self.head_or_tp_rank = self.tp_rank
             self.put_step = 1
 
+        soc_version = get_ascend_device_type()
+        # be removed later
+        if self.backend == "mooncake" and soc_version in {AscendDeviceType.A3}:
+            self.head_or_tp_rank = self.tp_rank
+            self.put_step = 1
+
         self.metadata = KeyMetadata(
             model_config.model.rstrip("/").split("/")[-1],
             self.head_or_tp_rank,
@@ -140,11 +147,6 @@ class KVPoolWorker:
         backend_module = importlib.import_module(backend_path)
         real_backend = getattr(backend_module, backend_name)
 
-        # be removed later
-        if self.backend == "mooncake":
-            self.head_or_tp_rank = self.tp_rank
-            self.put_step = 1
-
         self.m_store = real_backend(  # type: ignore[misc]
             parallel_config
         )