pytorch/torch/quantization/quantize_fx.py
Vasiliy Kuznetsov 7094c09ff7 quantizaton: add API usage logging (#46095)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/46095

Adds logging on usage of public quantization APIs. This only works in FB codebase
and is a no-op in OSS.

Test Plan: The test plan is fb-only

Reviewed By: raghuramank100

Differential Revision: D24220817

fbshipit-source-id: a2cc957b5a077a70c318242f4a245426e48f75e5
2020-10-09 16:51:27 -07:00

245 lines
9.5 KiB
Python

import torch
from torch.fx import GraphModule # type: ignore
from torch.fx import symbolic_trace # type: ignore
from torch.fx.symbolic_trace import Tracer # type: ignore
from .fx import Fuser # noqa: F401
from .fx import Quantizer # noqa: F401
from .fx.utils import graph_pretty_str # noqa: F401
def _check_is_graph_module(model):
if not isinstance(model, GraphModule):
raise ValueError(
'input model must be a GraphModule, ' +
'Got type:' + str(type(model)) + ' Please make ' +
'sure to follow the tutorials.')
def _fuse_fx(graph_module, inplace=False):
r""" Internal helper function to fuse modules in preparation for quantization
Args:
graph_module: GraphModule object from symbolic tracing (torch.fx.symbolic_trace)
"""
_check_is_graph_module(graph_module)
fuser = Fuser()
return fuser.fuse(graph_module, inplace)
class CustomTracer(Tracer):
def __init__(self, standalone_modules):
super().__init__()
self.standalone_modules = standalone_modules
def is_leaf_module(self, m, module_qualified_name):
return (m.__module__.startswith('torch.nn') and
not isinstance(m, torch.nn.Sequential)) or \
module_qualified_name in self.standalone_modules
def _prepare_fx(model, qconfig_dict, inplace, is_standalone_module=False):
r""" Internal helper function for prepare_fx
Args:
`model`, `qconfig_dict`, `inplace`: see docs for :func:`~torch.quantization.prepare_fx`
`is_standalone_module`: a boolean flag indicates whether we are
quantizing a standalone module or not, a standalone module
is a submodule of the parent module that is not inlined in the
forward graph of the parent module,
the way we quantize standalone module is described in:
:func:`~torch.quantization._prepare_standalone_module_fx`
"""
# symbolically trace the model
if is_standalone_module:
# standlone module is traced before quantizing standalone modules
graph_module = symbolic_trace(model)
else:
standalone_modules = qconfig_dict.get('standalone_module_name', [])
# skipping tracing standalone modules when tracing top level module
graph_module = GraphModule(model, CustomTracer(standalone_modules).trace(model))
graph_module = _fuse_fx(graph_module, inplace)
quantizer = Quantizer()
return quantizer.prepare(graph_module, qconfig_dict, inplace=True, is_standalone_module=is_standalone_module)
def _prepare_standalone_module_fx(model, qconfig_dict, inplace=False):
r""" [Internal use only] Prepare a standalone module, so that it can be used when quantizing the
parent module.
standalone_module means it a submodule that is not inlined in parent module,
and will be quantized separately as one unit.
input of the module is quantized in parent module, output of the module
is quantized in the standalone module.
Extra attributes in output GraphModule while preparing a standalone module:
_standalone_module_observed_input_idxs(List[Int]): a list of indexs for the graph inputs that
needs to be observed in parent module
_output_is_observed(Bool): a boolean variable indicate whether the output of the
custom module is observed or not
"""
torch._C._log_api_usage_once("quantization_api.quantize_fx._prepare_standalone_module_fx")
return _prepare_fx(model, qconfig_dict, inplace, is_standalone_module=True)
def fuse_fx(model, inplace=False):
r""" Fuse modules like conv+bn, conv+bn+relu etc, model must be in eval mode.
Fusion rules are defined in torch.quantization.fx.fusion_pattern.py
Args:
`model`: a torch.nn.Module model
`inplace`: flag for whether we fuse modules inplace or out of place
Example:
```python
from torch.quantization import fuse_fx
m = Model().eval()
m = fuse_fx(m)
```
"""
torch._C._log_api_usage_once("quantization_api.quantize_fx.fuse_fx")
assert not model.training, 'fuse_fx only works on models in eval mode'
graph_module = torch.fx.symbolic_trace(model)
return _fuse_fx(graph_module, inplace)
def prepare_fx(model, qconfig_dict, inplace=False):
r""" Prepare a model for post training static quantization
Args:
`model`: torch.nn.Module model, must be in eval mode
`qconfig_dict`: qconfig_dict is a dictionary with the following configurations:
qconfig_dict = {
# optional, global config
"": qconfig?,
# optional, used for module and function types
# could also be split into module_types and function_types if we prefer
"object_type": [
(torch.nn.Conv2d, qconfig?),
(torch.nn.functional.add, qconfig?),
...,
],
# optional, used for module names
"module_name": [
("foo.bar", qconfig?)
...,
],
# optional, matched in order, first match takes precedence
"module_name_regex": [
("foo.*bar.*conv[0-9]+", qconfig?)
...,
],
# priority (in increasing order): global, object_type, module_name_regex, module_name
# qconfig == None means fusion and quantization should be skipped for anything
# matching the rule
# optional: specify the path for standalone modules
# These modules are symbolically traced and quantized as one unit
"standalone_module_name": [
"submodule.standalone"
]
}
`inplace`: flag for carry out model transformations in-place,
the original module is mutated
Return:
A GraphModule with observer (configured by qconfig_dict), ready for calibration
Example:
```python
import torch
from torch.quantization import get_default_qconfig
from torch.quantization import prepare_fx
float_model.eval()
graph_module = torch.fx.symbolic_trace(float_model)
qconfig = get_default_qconfig('fbgemm')
def calibrate(model, data_loader):
model.eval()
with torch.no_grad():
for image, target in data_loader:
model(image)
qconfig_dict = {"": qconfig}
prepared_model = prepare_fx(graph_module, qconfig_dict)
# Run calibration
calibrate(prepared_model, sample_inference_data)
```
"""
torch._C._log_api_usage_once("quantization_api.quantize_fx.prepare_fx")
assert not model.training, 'prepare_fx only works for models in' + \
'eval mode'
return _prepare_fx(model, qconfig_dict, inplace)
def prepare_qat_fx(model, qconfig_dict, inplace=False):
r""" Prepare a model for quantization aware training
Args:
`model`: torch.nn.Module model, must be in train mode
`qconfig_dict`: see :func:`~torch.quantization.prepare_fx`
`inplace`: flag for carry out model transformations in-place,
the original module is mutated
Return:
A GraphModule with fake quant modules (configured by qconfig_dict), ready for
quantization aware training
Example:
```python
import torch
from torch.quantization import get_default_qat_qconfig
from torch.quantization import prepare_fx
qconfig = get_default_qat_qconfig('fbgemm')
def train_loop(model, train_data):
model.train()
for image, target in data_loader:
...
float_model.train()
qconfig_dict = {"": qconfig}
prepared_model = prepare_fx(float_model, qconfig_dict)
# Run calibration
train_loop(prepared_model, train_loop)
```
"""
torch._C._log_api_usage_once("quantization_api.quantize_fx.prepare_qat_fx")
assert model.training, 'prepare_qat_fx only works for models in ' + \
'train mode'
return _prepare_fx(model, qconfig_dict, inplace)
def _convert_fx(graph_module, inplace, debug, is_standalone_module=False):
""" `is_standalone_module`: see docs in :func:`~torch.quantization.prepare_standalone_module_fx`
"""
_check_is_graph_module(graph_module)
quantizer = Quantizer()
return quantizer.convert(graph_module, inplace, debug, is_standalone_module)
def convert_fx(graph_module, inplace=False, debug=False):
r""" Convert a calibrated or trained model to a quantized model
Args:
`graph_module`: A prepared and calibrated/trained model (GraphModule)
`inplace`: flag for carry out model transformations in-place,
the original module is mutated
`debug`: flag for producing a debug friendly model (preserve weight attribute)
Return:
A quantized model (GraphModule)
Example:
```python
# prepared_model: the model after prepare_fx/prepare_qat_fx and calibration/training
quantized_model = convert_fx(prepared_model)
```
"""
torch._C._log_api_usage_once("quantization_api.quantize_fx.convert_fx")
return _convert_fx(graph_module, inplace, debug)
def _convert_standalone_module_fx(graph_module, inplace=False, debug=False):
r""" [Internal use only] Convert a model produced by :func:`~torch.quantization.prepare_standalone_module_fx`
and convert it to a quantized model
The inputs will be quantized by parent module, checks `_standalone_module_observed_input_idxs` of
input model and will treat these inputs as quantized
also will not dequantize the final output
Return:
A quantized standalone module which accepts quantized input(if needed)
and produces quantized output (if needed).
"""
torch._C._log_api_usage_once("quantization_api.quantize_fx._convert_standalone_module_fx")
return _convert_fx(graph_module, inplace, debug, is_standalone_module=True)