Abstract accelerator (step 1) (#2504)

* Establish building block of abstract accelerator

* Change .*Tensor variable to @Property

* [op builder] add op builder reflection to allow enumerate of builders in all_ops.py and builder_names.py

* change @abstractproperty to @Property @AbstractMethod

Co-authored-by: Olatunji Ruwase <[email protected]>

deepspeed/accelerator/__init__.py

@@ -0,0 +1,2 @@
+from .abstract_accelerator import DeepSpeedAccelerator
+from .real_accelerator import get_accelerator, set_accelerator

deepspeed/accelerator/abstract_accelerator.py

@@ -0,0 +1,230 @@
+import abc
+from abc import ABC
+
+
+class DeepSpeedAccelerator(ABC):
+    def __init__(self):
+        self._name = None
+        self._communication_backend_name = None
+
+    # Device APIs
+    @abc.abstractmethod
+    def device_name(self, device_index):
+        ...
+
+    @abc.abstractmethod
+    def device(self, device_index):
+        ...
+
+    @abc.abstractmethod
+    def set_device(self, device_index):
+        ...
+
+    @abc.abstractmethod
+    def current_device(self):
+        ...
+
+    @abc.abstractmethod
+    def current_device_name(self):
+        ...
+
+    @abc.abstractmethod
+    def device_count(self):
+        ...
+
+    @abc.abstractmethod
+    def synchronize(self, device_index=None):
+        ...
+
+    # RNG APIs
+    @abc.abstractmethod
+    def random(self):
+        ...
+
+    @abc.abstractmethod
+    def set_rng_state(self, new_state, device_index=None):
+        ...
+
+    @abc.abstractmethod
+    def get_rng_state(self, device_index=None):
+        ...
+
+    @abc.abstractmethod
+    def manual_seed(self, seed):
+        ...
+
+    @abc.abstractmethod
+    def manual_seed_all(self, seed):
+        ...
+
+    @abc.abstractmethod
+    def initial_seed(self, seed):
+        ...
+
+    @abc.abstractmethod
+    def default_generator(self, device_index):
+        ...
+
+    # Streams/Events
+    @abc.abstractmethod
+    def Stream(self, device=None, priority=0, **kwargs):
+        ...
+
+    @abc.abstractmethod
+    def StreamContext(self, stream):
+        ...
+
+    @abc.abstractmethod
+    def stream(self, stream):
+        ...
+
+    @abc.abstractmethod
+    def current_stream(self, device_index=None):
+        ...
+
+    @abc.abstractmethod
+    def default_stream(self, device_index=None):
+        ...
+
+    @abc.abstractmethod
+    def Event(self, **kwargs):
+        ...
+
+    # Memory management
+    @abc.abstractmethod
+    def empty_cache(self):
+        ...
+
+    @abc.abstractmethod
+    def memory_allocated(self, device_index=None):
+        ...
+
+    @abc.abstractmethod
+    def max_memory_allocated(self, device_index=None):
+        ...
+
+    @abc.abstractmethod
+    def reset_max_memory_allocated(self, device_index=None):
+        ...
+
+    @abc.abstractmethod
+    def memory_cached(self, device_index=None):
+        ...
+
+    @abc.abstractmethod
+    def max_memory_cached(self, device_index=None):
+        ...
+
+    @abc.abstractmethod
+    def reset_max_memory_cached(self, device_index=None):
+        ...
+
+    @abc.abstractmethod
+    def memory_stats(self, device_index=None):
+        ...
+
+    @abc.abstractmethod
+    def reset_peak_memory_stats(self, device_index=None):
+        ...
+
+    @abc.abstractmethod
+    def memory_reserved(self, device_index=None):
+        ...
+
+    @abc.abstractmethod
+    def max_memory_reserved(self, device_index=None):
+        ...
+
+    @abc.abstractmethod
+    def total_memory(self, device_index=None):
+        ...
+
+    # Data types
+    @abc.abstractmethod
+    def is_bf16_supported(self):
+        ...
+
+    @abc.abstractmethod
+    def is_fp16_supported(self):
+        ...
+
+    # Misc
+    @abc.abstractmethod
+    def amp(self):
+        ...
+
+    @abc.abstractmethod
+    def is_available(self):
+        ...
+
+    @abc.abstractmethod
+    def range_push(self, msg):
+        ...
+
+    @abc.abstractmethod
+    def range_pop(self):
+        ...
+
+    @abc.abstractmethod
+    def lazy_call(self, callback):
+        ...
+
+    @abc.abstractmethod
+    def communication_backend_name(self):
+        ...
+
+    # Tensor operations
+    @property
+    @abc.abstractmethod
+    def BFloat16Tensor(self):
+        ...
+
+    @property
+    @abc.abstractmethod
+    def ByteTensor(self):
+        ...
+
+    @property
+    @abc.abstractmethod
+    def DoubleTensor(self):
+        ...
+
+    @property
+    @abc.abstractmethod
+    def FloatTensor(self):
+        ...
+
+    @property
+    @abc.abstractmethod
+    def HalfTensor(self):
+        ...
+
+    @property
+    @abc.abstractmethod
+    def IntTensor(self):
+        ...
+
+    @property
+    @abc.abstractmethod
+    def LongTensor(self):
+        ...
+
+    @abc.abstractmethod
+    def pin_memory(self, tensor):
+        ...
+
+    @abc.abstractmethod
+    def on_accelerator(self, tensor):
+        ...
+
+    @abc.abstractmethod
+    def op_builder_dir(self):
+        ...
+
+    @abc.abstractmethod
+    def create_op_builder(self, class_name):
+        ...
+
+    @abc.abstractmethod
+    def build_extension(self):
+        ...