init v0.23.0

Signed-off-by: Sun Ruoxi <sunruoxi@4paradigm.com>

vllm_ascend/memcache_comm_fence.py

@@ -0,0 +1,91 @@
+#
+# Copyright (c) 2025 Huawei Technologies Co., Ltd. All Rights Reserved.
+#
+# 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 __future__ import annotations
+
+import threading
+
+import torch
+
+_lock = threading.RLock()
+_attention_compute_start_gate: AttentionComputeStartGate | None = None
+
+
+class AttentionComputeStartGate:
+    """Gate that opens when the compute stream reaches attention.
+
+    The attention worker records an NPU event immediately before submitting the
+    attention op. MemCache worker threads wait for that event to complete before
+    submitting H2D/L2G work, so transfer starts when the compute stream is
+    actually at the attention boundary rather than merely after the Python call
+    site was reached.
+    """
+
+    def __init__(self) -> None:
+        self._condition = threading.Condition()
+        self._event: torch.npu.Event | None = None
+
+    def record(
+        self,
+        stream: torch.npu.Stream | None = None,
+    ) -> None:
+        stream = stream or torch.npu.current_stream()
+        event = torch.npu.Event()
+        event.record(stream)
+        with self._condition:
+            if self._event is None:
+                self._event = event
+                self._condition.notify_all()
+
+    def wait(self, timeout: float = 10.0) -> bool:
+        with self._condition:
+            while self._event is None:
+                if not self._condition.wait(timeout=timeout):
+                    return False
+            event = self._event
+
+        event.synchronize()
+        return True
+
+
+def reset_attention_compute_start_gate() -> AttentionComputeStartGate:
+    """Create a new per-layer gate for MemCache work.
+
+    Layerwise prefetch tasks keep a reference to the gate that was current when
+    they were submitted. The attention path opens that same gate when attention
+    compute is about to be launched.
+    """
+    global _attention_compute_start_gate
+    gate = AttentionComputeStartGate()
+    with _lock:
+        _attention_compute_start_gate = gate
+    return gate
+
+
+def get_attention_compute_start_gate() -> AttentionComputeStartGate:
+    with _lock:
+        gate = _attention_compute_start_gate
+    if gate is None:
+        gate = reset_attention_compute_start_gate()
+    return gate
+
+
+def record_attention_compute_start() -> None:
+    """Record the compute-stream boundary immediately before attention."""
+    with _lock:
+        gate = _attention_compute_start_gate
+    if gate is not None:
+        gate.record()