chore: import upstream snapshot with attribution

python/paddle/distributed/fleet/meta_parallel/pipeline_hooks.py

@@ -0,0 +1,56 @@
+# Copyright (c) 2024 PaddlePaddle Authors. 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
+
+from collections import defaultdict
+from typing import TYPE_CHECKING
+
+if TYPE_CHECKING:
+    from collections.abc import Callable
+
+
+class PipelineHook:
+    def __init__(self):
+        self.hooks: dict[int, list[Callable]] = defaultdict(list)
+        self._hooks_capacity = 0
+        self.reset_current_id()
+
+    def reset_current_id(self):
+        self._current_id = 0
+
+    def set_hooks_capacity(self, capacity: int):
+        self._hooks_capacity = capacity
+
+    def register_hook(self, hook_id: int, hook: Callable):
+        assert hook_id < self._hooks_capacity, (
+            f"hook_id {hook_id} is out of range, maximum capacity is {self._hooks_capacity}."
+        )
+        self.hooks[hook_id].append(hook)
+
+    def run_hook(self):
+        assert self._current_id < self._hooks_capacity, (
+            f"hook_id {self._current_id} is out of range, maximum capacity is {self._hooks_capacity}."
+        )
+        for hook in self.hooks[self._current_id]:
+            hook(self._current_id)
+        self._current_id += 1
+
+    @property
+    def current_id(self):
+        return self._current_id
+
+    @property
+    def hooks_capacity(self):
+        return self._hooks_capacity