pytorch/caffe2/python/scope.py
Zhiping Xiu 1423c0d9f1 Add EmptyNameScope to allow you jump out from current scope. (#14631)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/14631

adding a empty name scope to allow people jump out from current namescope.

This could be useful when you want to access blob from parent or sibling scope.

 Facebook:

e.g: we encoutered a potential usecase in D13124249 (it's a large diff, please search by EmptyNameScope in that diff), we need to access to a blob declared in root namescope from a device namescope (device namescope has been used by parallel_GPU API). `EmptyNameScope` can help us do that with ease.

I referenced to `EmptyDeviceScope` D6103412 while implementing this one.

Reviewed By: yinghai

Differential Revision: D13272240

fbshipit-source-id: d4cde5abcc2336e456b6c6ef086266ef94d86da8
2018-12-12 01:39:50 -08:00

123 lines
3.7 KiB
Python

## @package scope
# Module caffe2.python.scope
from __future__ import absolute_import
from __future__ import division
from __future__ import print_function
from __future__ import unicode_literals
import contextlib
import threading
from past.builtins import basestring
from caffe2.proto import caffe2_pb2
# The name scope and device scope when creating a new operator.
_NAMESCOPE_SEPARATOR = '/'
_threadlocal_scope = threading.local()
def CurrentNameScope():
global _threadlocal_scope
if not hasattr(_threadlocal_scope, "namescope"):
_threadlocal_scope.namescope = ''
return _threadlocal_scope.namescope
def CurrentDeviceScope():
global _threadlocal_scope
if not hasattr(_threadlocal_scope, "devicescope"):
_threadlocal_scope.devicescope = None
return _threadlocal_scope.devicescope
@contextlib.contextmanager
def NameScope(prefix, reset=False):
global _threadlocal_scope
assert isinstance(prefix, basestring) or prefix is None, \
"NameScope takes in a string as its argument."
old_scope = CurrentNameScope()
prefix = prefix + _NAMESCOPE_SEPARATOR if prefix else ''
if reset:
_threadlocal_scope.namescope = prefix
else:
_threadlocal_scope.namescope = _threadlocal_scope.namescope + prefix
try:
yield
finally:
assert _threadlocal_scope.namescope.endswith(prefix), \
"The namescope variable is changed from outside NameScope() calls."
_threadlocal_scope.namescope = old_scope
@contextlib.contextmanager
def DeviceScope(scope, node_name=None):
new_scope = caffe2_pb2.DeviceOption()
if scope:
assert isinstance(scope, caffe2_pb2.DeviceOption), \
"DeviceScope takes in a caffe2_pb2.DeviceOption as its argument."
new_scope.CopyFrom(scope)
else:
assert node_name, "At least one argument should be non-null in DeviceScope"
# rewrite node_name if it is explicitly given
if node_name:
new_scope.node_name = node_name
global _threadlocal_scope
old_scope = CurrentDeviceScope()
# nested scope should inherit the node_name if it is not explicitly set
if old_scope and old_scope.HasField('node_name') and \
not new_scope.HasField('node_name'):
new_scope.node_name = old_scope.node_name
# nested scope should inherit the extra_info and merged it with new extra_info
if old_scope and hasattr(old_scope, 'extra_info'):
new_scope.extra_info.extend(old_scope.extra_info)
new_scope.extra_info.sort()
_threadlocal_scope.devicescope = new_scope
try:
yield
finally:
assert _threadlocal_scope.devicescope == new_scope, \
"The device scope is changed from outside DeviceScope() calls."
_threadlocal_scope.devicescope = old_scope
@contextlib.contextmanager
def EmptyNameScope():
"""
Allow users to 'disable' the name scope behaviour.
This sets the CurrentNameScope() to None, so that the field is
not set in CreateOperator(...), etc.
"""
old_scope = CurrentNameScope()
try:
_threadlocal_scope.namescope = ''
yield
finally:
_threadlocal_scope.namescope = old_scope
return
@contextlib.contextmanager
def EmptyDeviceScope():
"""
Allow users to 'disable' the device scope behaviour (so it can be
controlled at a NetDef::DeviceOption level, not overridden at
OperatorDef::DeviceOption level).
This sets the CurrentDeviceScope() to None, so that the field is
not set in CreateOperator(...), etc.
"""
old_scope = CurrentDeviceScope()
try:
_threadlocal_scope.devicescope = None
yield
finally:
_threadlocal_scope.devicescope = old_scope
return