[tensor] hijack addmm for colo tensor (#923)

* hijack addmm for colo tensor

* fix bugs

* polish unit test

* polish comments

colossalai/tensor/_ops/__init__.py

@@ -2,4 +2,5 @@ from .linear import colo_linear
 from .element_wise import *
 from .layernorm import colo_layernorm
 from .loss import colo_cross_entropy
-from .embedding import colo_embedding
+from .embedding import colo_embedding
+from .addmm import colo_addmm

colossalai/tensor/_ops/addmm.py

@@ -0,0 +1,115 @@
+import torch
+from typing import Union
+from colossalai.tensor.op_wrapper import colo_op_impl
+from colossalai.nn.layer.parallel_1d._utils import split_forward_gather_backward, reduce_input, reduce_grad
+from colossalai.nn.layer.utils import divide
+from colossalai.core import global_context as gpc
+from colossalai.tensor import ComputePattern, TensorSpec, ComputePattern, ParallelAction, ColoTensor, ShardPattern
+from colossalai.tensor.graph import GraphOpNode, GraphGlobalEnv
+
+
+def colo_addmm_1Drow(input_tensor: ColoTensor, mat1: ColoTensor, mat2: ColoTensor, beta: Union[int, float],
+                     alpha: Union[int, float]) -> ColoTensor:
+    parallel_action = mat2.shard_spec.get_action_by_compute_pattern(ComputePattern.TP1DRow_mm)
+    # mat1:S[1] x mat2:S[0] = Output:P
+    # beta * input + alpha * All-Reduce(Output) = res
+
+    # mat1:S[1]
+    if mat1.is_gathered():
+        # Not splited yet.
+        assert divide(mat1.shape[-1], gpc.tensor_parallel_size) == mat2.size(0), \
+            'Invalid shapes in 1Drow forward: mat1={}, mat2={}. Expected last dim of input {}.'.format(
+            mat1.shape, mat2.shape, mat2.size(0) * gpc.tensor_parallel_size)
+        input_per_partition = split_forward_gather_backward(mat1.torch_tensor(), parallel_action.parallel_mode, dim=-1)
+    elif mat1.shard_pattern == ShardPattern.Col:
+        # Splited by 1Dcol
+        assert mat1.shape[-1] == mat2.size(0), \
+            'Invalid shapes in 1Drow forward: mat1={}, mat2={}. Expected last dim of input {}.'.format(
+            mat1.shape, mat2.shape, mat2.size(0))
+        input_per_partition = mat1.torch_tensor()
+    else:
+        raise NotImplementedError
+
+    # Output:P
+    partial_output = torch.mm(input_per_partition, mat2.torch_tensor())
+    # Reduce(Output)
+    output = reduce_input(partial_output, parallel_action.parallel_mode)
+    # input
+    assert not input_tensor.has_spec(), 'Invalid input spec for 1Drow addmm op'
+    output = beta * input_tensor.torch_tensor() + alpha * output
+    output = ColoTensor.init_from_torch_tensor(output)
+    return output
+
+
+def colo_addmm_1Dcol(input_tensor: ColoTensor, mat1: ColoTensor, mat2: ColoTensor, beta: Union[int, float],
+                     alpha: Union[int, float]) -> ColoTensor:
+    # mat1:B x mat2:S[1] + input:S[1] = Output:S[1]
+    # All-Gather(Output)
+    # mat1:B
+    parallel_action = mat2.shard_spec.get_action_by_compute_pattern(ComputePattern.TP1DCol_mm)
+    if mat1.is_gathered():
+        # Not splited yet.
+        assert mat1.shape[-1] == mat2.size(0), \
+            'Invalid shapes in 1Dcol forward: mat1={}, mat2={}. Expected last dim of input {}.'.format(
+                mat1.shape, mat2.shape, mat2.size(0))
+        input_parallel = reduce_grad(mat1.torch_tensor(), parallel_action.parallel_mode)
+
+    # input:S[1]
+    assert input_tensor.has_spec() and input_tensor.shard_spec.num_action == 1 and \
+        input_tensor.shard_pattern in [ShardPattern.Col, ShardPattern.Row], \
+        'Invalid bias spec for 1Dcol Linear op'
+
+    output_parallel = torch.addmm(input_tensor.torch_tensor(),
+                                  input_parallel,
+                                  mat2.torch_tensor(),
+                                  beta=beta,
+                                  alpha=alpha)
+
+    output = ColoTensor.init_from_torch_tensor(output_parallel)
+    out_parallel_action_list = [ParallelAction(priority=1, parallel_mode=parallel_action.parallel_mode)]
+    output_spec = TensorSpec(out_parallel_action_list)
+    output.set_spec(output_spec, shard=False)
+    output.set_shard_pattern(ShardPattern.Col)
+    if parallel_action.gather_out:
+        # All-Gather(Output)
+        output.gather()
+    return output
+
+
+@colo_op_impl(torch.addmm)
+def colo_addmm(types, args, kwargs, pg):
+    """Handles ``__torch_function__`` dispatch for ``torch.nn.functional.linear``.
+    This method computes a linear.
+    """
+    input_tensor, mat1, mat2 = tuple(
+        map(lambda t: t if isinstance(t, ColoTensor) else ColoTensor.init_from_torch_tensor(t), args[:3]))
+    beta = kwargs.get('beta', 1) if kwargs else 1
+    alpha = kwargs.get('alpha', 1) if kwargs else 1
+
+    # building the computing graph, inputs -> op
+    # if GraphGlobalEnv().graph_building:
+    #     cur_op_node = GraphOpNode('linear', [weight, bias])
+    #     cur_op_node.add_prev_tensor(input_tensor)
+
+    # Add communication logic before and after linear call.
+    ret_tensor = None
+    if not mat2.has_spec():    # No Model Parallel Applied
+        assert not input_tensor.has_spec(), 'Invalid input spec for native addmm op'
+        ret_tensor = ColoTensor.init_from_torch_tensor(
+            torch.addbmm(input_tensor.torch_tensor(), mat1.torch_tensor(), mat2.torch_tensor(), beta=beta, alpha=alpha))
+    elif mat2.shard_spec.num_action == 1:    # Single Model Parallel Applied
+        compute_patterns = mat2.shard_spec.compute_patterns
+        if ComputePattern.TP1DRow_mm in compute_patterns:
+            ret_tensor = colo_addmm_1Drow(input_tensor, mat1, mat2, beta, alpha)
+        elif ComputePattern.TP1DCol_mm in compute_patterns:
+            ret_tensor = colo_addmm_1Dcol(input_tensor, mat1, mat2, beta, alpha)
+        else:
+            raise NotImplementedError
+    else:
+        raise NotImplementedError
+
+    # building the computing graph, op -> output
+    # if GraphGlobalEnv().graph_building:
+    #     cur_op_node.add_post_tensor(ret_tensor)
+
+    return ret_tensor

colossalai/tensor/colo_tensor.py

@@ -142,12 +142,15 @@ class ColoTensor(object):
         # Model Parameters
         if self._shard_spec.num_action == 1:
             parallel_action = self._shard_spec.get_action_by_compute_pattern(self._shard_spec.compute_patterns[0])
-            if parallel_action.compute_pattern in [ComputePattern.TP1DRow_Linear, \
-                ComputePattern.TP1DCol_Embedding]:
+            if parallel_action.compute_pattern in [
+                    ComputePattern.TP1DRow_Linear, ComputePattern.TP1DCol_Embedding, ComputePattern.TP1DCol_mm
+            ]:
                 self._shard_1d(parallel_action=parallel_action, dim=-1)
-                self._shard_pattern = ShardPattern.Col    # We bind our ComputePattern on weight, which has to be transposed when linear().
-            elif parallel_action.compute_pattern in [ComputePattern.TP1DCol_Linear, \
-                ComputePattern.TP1DRow_Embedding]:
+                # We bind our ComputePattern on weight, which has to be transposed when linear().
+                self._shard_pattern = ShardPattern.Col
+            elif parallel_action.compute_pattern in [
+                    ComputePattern.TP1DCol_Linear, ComputePattern.TP1DRow_Embedding, ComputePattern.TP1DRow_mm
+            ]:
                 self._shard_1d(parallel_action=parallel_action, dim=0)
                 self._shard_pattern = ShardPattern.Row
             else:

colossalai/tensor/spec.py

@@ -8,8 +8,10 @@ class ComputePattern(Enum):
     TP1DCol_Linear = 2
     TP1DRow_Embedding = 3
     TP1DCol_Embedding = 4
-    ZeRO = 5
-    DP = 6
+    TP1DRow_mm = 5
+    TP1DCol_mm = 6
+    ZeRO = 7
+    DP = 8
 
 
 class ShardPattern(Enum):