ColossalAI/colossalai/fx/passes/utils.py

331 lines
12 KiB
Python

import torch
from typing import Dict, Set
from torch.fx.node import Node, map_arg
from torch.fx.graph import Graph
from torch.fx.graph_module import GraphModule
def get_comm_size(prev_partition, next_partition):
"""
Given two partitions (parent and child),
calculate the communication size between the two.
"""
# Keep tracking the communication size between parent and child
comm_size = 0
# Keep tracking all the counted node
visited_nodes = set()
# Go through all nodes in the child partition
# If a node has input nodes from the parent partition,
# the output size of those input nodes will be counted
# and added to comm_size
parent_node_names = [n.name for n in prev_partition.graph.nodes]
for node in next_partition.graph.nodes:
input_nodes: Dict[Node, None] = {}
map_arg(node.args, lambda n: input_nodes.setdefault(n))
map_arg(node.kwargs, lambda n: input_nodes.setdefault(n))
for n in input_nodes:
if n.name in parent_node_names and n not in visited_nodes:
comm_size += n.meta['tensor_meta'].numel
visited_nodes.add(n)
return comm_size
def get_leaf(graph: Graph):
"""
Given a graph, return leaf nodes of this graph.
Note: If we remove ``root`` nodes, ``placeholder`` nodes, and ``output`` nodes from fx graph,
we will get a normal DAG. Leaf nodes in this context means leaf nodes in that DAG.
"""
input_nodes: Dict[Node, None] = {}
for node in graph.nodes:
if node.op == 'output':
map_arg(node.args, lambda n: input_nodes.setdefault(n))
map_arg(node.kwargs, lambda n: input_nodes.setdefault(n))
placeholder_nodes = []
for node in input_nodes.keys():
if node.op == 'placeholder':
placeholder_nodes.append(node)
for node in placeholder_nodes:
input_nodes.pop(node)
return list(input_nodes.keys())
def is_leaf(graph: Graph, node: Node):
return node in get_leaf(graph)
def get_top(graph: Graph):
"""
Given a graph, return top nodes of this graph.
Note: If we remove ``root`` nodes, ``placeholder`` nodes, and ``output`` nodes from fx graph,
we will get a normal DAG. Top nodes in this context means nodes with BFS level 0 in that DAG.
"""
top_node_list = set()
for node in graph.nodes:
if node.op == 'output':
continue
is_top = False
def _get_top(node):
nonlocal is_top
if node.op == 'placeholder':
is_top = True
map_arg(node.args, lambda n: _get_top(n))
map_arg(node.kwargs, lambda n: _get_top(n))
if is_top:
top_node_list.add(node)
return list(top_node_list)
def is_top(graph: Graph, node: Node):
return node in get_top(graph)
def get_all_consumers(graph: Graph, node: Node):
"""
Given a graph and a node of this graph, return all consumers of the node.
Returns:
List of ``Nodes`` that node appear in these nodes ``args`` and ``kwargs``.
"""
consumer_list = []
for n in graph.nodes:
if node in n.all_input_nodes:
consumer_list.append(n)
return consumer_list
def assign_bfs_level_to_nodes(graph: Graph):
"""
Give a graph, assign bfs level to each node of this graph excluding ``placeholder`` and ``output`` nodes.
Example:
class MLP(torch.nn.Module):
def __init__(self, dim: int):
super().__init__()
self.linear1 = torch.nn.Linear(dim, dim)
self.linear2 = torch.nn.Linear(dim, dim)
self.linear3 = torch.nn.Linear(dim, dim)
self.linear4 = torch.nn.Linear(dim, dim)
self.linear5 = torch.nn.Linear(dim, dim)
def forward(self, x):
l1 = self.linear1(x)
l2 = self.linear2(x)
l3 = self.linear3(l1)
l4 = self.linear4(l2)
l5 = self.linear5(l3)
return l4, l5
model = MLP(4)
gm = symbolic_trace(model)
print(gm.graph)
assign_bfs_level_to_nodes(gm.graph)
for node in gm.graph.nodes:
if hasattr(node, 'bfs_level'):
print(node.name, node.bfs_level)
Output:
graph():
%x : [#users=2] = placeholder[target=x]
%linear1 : [#users=1] = call_module[target=linear1](args = (%x,), kwargs = {})
%linear2 : [#users=1] = call_module[target=linear2](args = (%x,), kwargs = {})
%linear3 : [#users=1] = call_module[target=linear3](args = (%linear1,), kwargs = {})
%linear4 : [#users=1] = call_module[target=linear4](args = (%linear2,), kwargs = {})
%linear5 : [#users=1] = call_module[target=linear5](args = (%linear3,), kwargs = {})
return (linear4, linear5)
linear1 0
linear2 0
linear3 1
linear4 1
linear5 2
"""
current_level = 0
nodes_to_process = []
top_nodes = get_top(graph)
for node in top_nodes:
node.bfs_level = current_level
nodes_to_process.extend(get_all_consumers(graph, node))
current_level += 1
while nodes_to_process:
new_process_list = []
for node in nodes_to_process:
if node.op == 'output':
continue
node.bfs_level = current_level
new_process_list.extend(get_all_consumers(graph, node))
nodes_to_process = new_process_list
current_level += 1
def get_node_module(node) -> torch.nn.Module:
"""
Find the module associated with the given node.
Args:
node (torch.fx.Node): a torch.fx.Node object in the fx computation graph
Returns:
torch.nn.Module: the module associated with the given node
"""
assert node.graph.owning_module is not None, 'Cannot find the owning_module for node.graph, please make sure the graph is associated with a GraphModule object'
assert node.op == 'call_module', f'Expected node.op to be call_module, but found {node.op}'
module = node.graph.owning_module.get_submodule(node.target)
return module
def find_def_in_partition(node, partitions, input_partitions=None, direct=False):
# find def in input
if input_partitions is not None:
for placeholder in input_partitions:
if placeholder.name == node.name:
return 'MODEL_INPUT'
# find direct def
if direct:
for partition in partitions:
if node == partition:
return partition.name
# find def with getitem call
else:
for partition in partitions:
if node in partition.users.keys():
return partition.name
print(f'Not found def in partition {node.name}')
return None
def find_user_in_partition(node, partitions, output_partitions=None, direct=False):
user_partition_names = []
# find direct user
if direct:
for partition in partitions:
if node == partition:
user_partition_names.append(partition.name)
# find user with getitem call
else:
for partition in partitions:
if node in partition.args:
user_partition_names.append(partition.name)
if output_partitions is not None:
output_node = output_partitions[0]
if node.op == output_node.op:
user_partition_names.append('MODEL_OUTPUT')
if len(user_partition_names) > 0:
return user_partition_names
print(f'Not found user in partition {node.name}')
return None
def get_partition_depends(partition, partitions, input_partitions=None, output_partitions=None):
# e.g. Partition2: {input: {Partition0: [sub1_1], Partition1: [sub2_0]}, output:{Output: [sub3_0]}},
input = {}
output = {}
for offset, arg in enumerate(partition.args):
def_partition_name = None
if not arg.name.startswith('getitem'):
def_partition_name = find_def_in_partition(arg, partitions, input_partitions, direct=True)
else:
def_partition_name = find_def_in_partition(arg, partitions, input_partitions, direct=False)
if def_partition_name is None:
continue
if def_partition_name not in input:
input[def_partition_name] = []
input[def_partition_name].append(offset)
offset = -1
for user in partition.users.keys():
user_partition_names = None
if input_partitions is None or not user.name.startswith('getitem'):
user_partition_names = find_user_in_partition(user, partitions, output_partitions, direct=True)
offset = 0
else:
user_partition_names = find_user_in_partition(user, partitions, output_partitions, direct=False)
offset += 1
if user_partition_names is None:
continue
for user_partition_name in user_partition_names:
if user_partition_name not in output:
output[user_partition_name] = []
output[user_partition_name].append(offset)
return input, output, offset+1
# DAG just looks like following case.
# the int in every list represents the offset of the partition's input arg or output arg.
# {
# 'input_partition': {
# 'input_ids': {
# 'input': {},
# 'output': {'submod_0': [0], 'submod_1': [1]},
# 'output_len': 0},
# 'attention_mask': {
# 'input': {},
# 'output': {'submod_2': [0]},
# 'output_len': 0}},
# 'submod_0': {
# 'input': {'MODEL_INPUT': [0]},
# 'output': {'submod_1': [0], 'submod_2': [0, 1]},
# 'output_len': 2},
# 'submod_1': {
# 'input': {'submod_0': [0], 'MODEL_INPUT': [1]},
# 'output': {'submod_2': [0]},
# 'output_len': 1},
# 'submod_2': {
# 'input': {'MODEL_INPUT': [0], 'submod_0': [1, 2]},
# 'output': {'submod_3': [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11,
# 12, 13, 14, 15, 16, 17, 18, 19, 20, 21,
# 22, 23, 24]},
# 'output_len': 25},
# 'submod_3': {
# 'input': {'submod_2': [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11,
# 12, 13, 14, 15, 16, 17, 18, 19, 20,
# 21, 22, 23, 24]},
# 'output': {'MODEL_OUTPUT': [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10,
# 11, 12, 13, 14, 15, 16, 17, 18, 19,
# 20, 21, 22, 23, 24]},
# 'output_len': 25},
# 'output_partition': {
# 'input': {'logits': 'submod_3', 'past_key_values': (('submod_3', 'submod_3'), ('submod_3', 'submod_3'),
# ('submod_3', 'submod_3'), ('submod_3', 'submod_3'),
# ('submod_3', 'submod_3'), ('submod_3', 'submod_3'),
# ('submod_3', 'submod_3'), ('submod_3', 'submod_3'),
# ('submod_3', 'submod_3'), ('submod_3', 'submod_3'),
# ('submod_3', 'submod_3'), ('submod_3', 'submod_3'))},
# 'output': {}, 'output_len': 0}
# }
# TODO(jiangziyue) Define a Class for DAG.
def get_DAG(gm: GraphModule):
DAG = {}
input_partitions = []
partitions = []
output_partitions = []
for node in gm.graph.nodes:
if node.op == 'placeholder':
input_partitions.append(node)
elif node.name.startswith('submod_'):
partitions.append(node)
elif node.op == 'output':
output_partitions.append(node)
for partition in input_partitions:
DAG_node = {'input': {}, 'output': {}, 'output_len': 1}
_, output, _ = get_partition_depends(partition, partitions, None, output_partitions)
DAG_node['output'] = output
if 'input_partition' not in DAG:
DAG['input_partition'] = {}
DAG['input_partition'][partition.name] = DAG_node
for partition in partitions:
DAG_node = {'input': {}, 'output': {}}
DAG_node['input'], DAG_node['output'], DAG_node['output_len'] = get_partition_depends(partition, partitions, input_partitions, output_partitions)
DAG[partition.name] = DAG_node
for partition in output_partitions:
DAG_node = {'input': {}, 'output': {}, 'output_len': 0}
DAG_node['input'] = torch.fx.graph.map_arg(partition.args[0], lambda n: find_def_in_partition(n, partitions, input_partitions))
DAG['output_partition'] = DAG_node
return DAG