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paddlepaddle--paddle/python/paddle/static/amp/fp16_utils.py
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# Copyright (c) 2019 PaddlePaddle Authors. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
from __future__ import annotations
import logging
from dataclasses import dataclass
import numpy as np
import paddle
from paddle.base import core, framework, global_scope
from paddle.base.framework import in_pir_mode
from paddle.base.log_helper import get_logger
from paddle.base.wrapped_decorator import signature_safe_contextmanager
from .fp16_lists import (
AutoMixedPrecisionLists,
black_list,
get_low_precision_dtypestr,
)
_logger = get_logger(
__name__, logging.INFO, fmt='%(asctime)s-%(levelname)s: %(message)s'
)
_valid_types = [
core.VarDesc.VarType.DENSE_TENSOR,
core.VarDesc.VarType.SELECTED_ROWS,
core.VarDesc.VarType.DENSE_TENSOR_ARRAY,
]
_fp16_guard_pattern = "__use_fp16__"
@dataclass
class AmpOptions:
enable: bool
custom_white_list: list[str] | None
custom_black_list: list[str] | None
level: str
dtype: str
use_promote: bool
DEFAULT_AMP_OPTIONS = AmpOptions(
enable=True,
custom_white_list=None,
custom_black_list=None,
level='O1',
dtype='float16',
use_promote=True,
)
def _rename_arg(op, old_name, new_name):
"""
If an op has old_name input and output, rename these input
args new_name.
Args:
op (Operator): Current operator.
old_name (str): The old name of input args.
new_name (str): The new name of input args.
"""
op_desc = op.desc
if isinstance(op_desc, tuple):
op_desc = op_desc[0]
op_desc._rename_input(old_name, new_name)
op_desc._rename_output(old_name, new_name)
def _rename_op_input(program, op_var_rename_map, origin_ops, keep_fp32_ops):
for block in program.blocks:
ops = block.ops
block_id = block.idx
for op in ops:
if op not in origin_ops or op in keep_fp32_ops:
continue
for name in op.input_arg_names:
if name in op_var_rename_map[block_id]:
op._rename_input(name, op_var_rename_map[block_id][name])
def _dtype_to_str(dtype):
"""
Convert specific variable type to its corresponding string.
Args:
dtype (VarType): Variable type.
"""
if dtype in [core.VarDesc.VarType.FP16, core.VarDesc.VarType.BF16]:
# TODO(Xreki): change the returned str to "bf16" for BF16 data type.
# Currently too many codes use "cast_fp16" as key.
return 'fp16'
else:
return 'fp32'
_keep_layer_norm_scale_bias_to_fp32_flag = True
def _keep_layer_norm_scale_bias_to_fp32(*args):
global _keep_layer_norm_scale_bias_to_fp32_flag
if len(args) == 0:
return _keep_layer_norm_scale_bias_to_fp32_flag
else:
assert len(args) == 1 and isinstance(args[0], bool)
old_value = _keep_layer_norm_scale_bias_to_fp32_flag
_keep_layer_norm_scale_bias_to_fp32_flag = args[0]
return old_value
def _keep_fp32_input(op, in_name):
op_type = op.type
if op_type == 'batch_norm':
# Scale, Bias, Mean, Variance should be float32.
return in_name != 'X'
if op_type == 'layer_norm' and _keep_layer_norm_scale_bias_to_fp32():
return in_name != 'X'
if op_type == 'instance_norm':
return in_name != 'X'
if op_type == 'fused_bn_add_activation':
return in_name not in {'X', 'Z'}
if op_type == 'resnet_unit':
return in_name not in {'X', 'FilterX', 'Z', 'FilterZ'}
if op_type in ['fused_attention', 'fused_feedforward']:
return in_name in {
'LnScale',
'LnBias',
'Ln2Scale',
'Ln2Bias',
"Ln1Scale",
"Ln1Bias",
}
if op_type == 'fused_multi_transformer':
return in_name in {'LnScale', 'LnBias', 'FFNLnScale', 'FFNLnBias'}
return False
def _keep_fp32_output(op, out_name):
op_type = op.type
if op_type in ['batch_norm', 'fused_bn_add_activation']:
return out_name != 'Y'
if op_type == 'layer_norm' and _keep_layer_norm_scale_bias_to_fp32():
return out_name != 'Y'
if op_type == 'resnet_unit':
return out_name not in {'Y', 'ConvX', 'ConvZ'}
if op_type in ['fused_attention', 'fused_feedforward']:
return out_name in {
'LnMean',
'LnVariance',
'Ln2Mean',
'Ln2Variance',
'Ln1Mean',
'Ln1Variance',
}
return False
def _insert_cast_op(block, op, idx, src_dtype, dest_dtype):
"""
Insert cast op and rename op's input.
Args:
block (Program): The block in which the operator is.
op (Operator): The operator to insert cast op.
idx (int): The index of current operator.
src_dtype (VarType): The input variable dtype of cast op.
dest_dtype (VarType): The output variable dtype of cast op.
Returns:
num_cast_op (int): The number of cast ops that have been inserted.
"""
num_cast_ops = 0
for in_name in op.input_names:
if src_dtype == paddle.float32 and _keep_fp32_input(op, in_name):
continue
for in_var_name in op.input(in_name):
in_var = block._find_var_recursive(in_var_name)
if in_var.type not in _valid_types or in_var.dtype == dest_dtype:
continue
# op's input is already casted to dest_dtype before. Set the in_var.name to cast_name.
cast_name = in_var.name + '.cast_' + _dtype_to_str(dest_dtype)
casted_var = block._find_var_recursive(cast_name)
if casted_var and casted_var.dtype == dest_dtype:
_rename_arg(op, in_var.name, casted_var.name)
continue
# insert cast for op's input.
if in_var.dtype == src_dtype:
out_var = block.vars.get(cast_name)
if out_var is None or out_var.dtype != dest_dtype:
op_device = op.attr('op_device')
# NOTE(wangxi): optimize for pipeline, reduce one send.
# if in_var is stop_gradient and prev_op device is `all`,
# set cast_op device to `all`, can reduce send cast_var.
# TODO: need remove this after we unified the dynamic
# and static pipeline interface.
if src_dtype == paddle.float32 and in_var.stop_gradient:
prev_op = None
if in_var.op is op:
prev_op = find_true_prev_op(
block.ops, op, in_var_name
)
elif in_var.op is not None:
prev_op = in_var.op
prev_op_device = None
if prev_op is not None:
prev_op_device = prev_op.attr('op_device')
if (
prev_op_device is not None
and 'all' in prev_op_device
):
op_device = prev_op_device
out_var = block.create_var(
name=cast_name,
dtype=dest_dtype,
persistable=False,
stop_gradient=in_var.stop_gradient,
)
# Only forward program will be inserted cast op, but some ops
# has no op_role attr, so here set it directly. eg. resnet_unit.
op_role = (
int(core.op_proto_and_checker_maker.OpRole.Forward)
if not op.has_attr('op_role')
else op.attr('op_role')
)
block._insert_op_without_sync(
idx,
type="cast",
inputs={"X": in_var},
outputs={"Out": out_var},
attrs={
"in_dtype": in_var.dtype,
"out_dtype": out_var.dtype,
"op_device": op_device,
"op_role": op_role,
},
)
num_cast_ops += 1
_rename_arg(op, in_var.name, out_var.name)
for attr_name in ['in_dtype', 'out_dtype', 'dtype']:
if op.has_attr(attr_name) and op.attr(attr_name) in FLOAT_TYPES:
op._set_attr(attr_name, dest_dtype)
return num_cast_ops
def find_true_prev_op(ops, cur_op, var_name):
"""
Find the true prev op that outputs var_name variable.
Args:
ops (list): A list of ops.
cur_op (Operator): Current operator which has var_name variable.
var_name (string): Variable name.
"""
prev_op = []
for op in ops:
if op == cur_op:
break
for out_name in op.output_names:
for out_var_name in op.output(out_name):
if out_var_name == var_name:
prev_op.append(op)
if prev_op:
if not len(prev_op) == 1:
raise ValueError(
"There must be only one previous op "
f"that outputs {var_name} variable"
)
else:
return prev_op[0]
return None
def find_true_post_op(ops, cur_op, var_name, search_all=False):
"""
if there are post ops, return them, if there is no post op,
return None instead.
Args:
ops (list): A list of ops.
cur_op (Operator): Current operator which has var_name variable.
var_name (string): Variable name.
search_all (bool): The type of operator search. Use if \"cur_op\" is not in the \"ops\" set.
"""
post_op = []
if search_all:
"""
\"cur_op\" do not have to be in list of \"ops\". E.g. \"cur_op\" can come
from startup_prog block and \"ops\" list from main_prog block.
By setting idx to -1, we'll start looking for post-ops from the top of the list.
If search_all is False, assume that \"cur_op\" is in \"ops\" list,
so to reduce the time of search we can start iterating from \"cur_op\" idx.
"""
idx = -1
else:
for idx, op in enumerate(ops):
if op == cur_op:
break
for i in range(idx + 1, len(ops)):
op = ops[i]
for in_name in op.input_names:
for in_var_name in op.input(in_name):
if in_var_name == var_name:
post_op.append(op)
return post_op
def find_op_index(block_desc, cur_op_desc):
""" """
for idx in range(block_desc.op_size()):
if cur_op_desc == block_desc.op(idx):
return idx
return -1
def _is_in_black_varnames(op, amp_lists):
for in_name in op.input_arg_names:
if in_name in amp_lists.black_varnames:
return True
for out_name in op.output_arg_names:
if out_name in amp_lists.black_varnames:
return True
return False
def _need_keep_fp32(op, unsupported_op_list, use_fp16_guard):
if op.type in unsupported_op_list:
# the highest priority condition: If ops don't have fp16 computing kernels,
# they must be executed in fp32 calculation pattern.
return True
# process ops about learning rate
in_out_arg_names = []
in_out_arg_names.extend(list(op.input_arg_names))
in_out_arg_names.extend(list(op.output_arg_names))
for name in in_out_arg_names:
if "learning_rate" in name:
return True
if use_fp16_guard:
if op.has_attr("op_namescope") and (
_fp16_guard_pattern in op.attr("op_namescope")
):
# op in fp16 guard
return False
else:
# op not in fp16 guard
return True
else:
return False
@signature_safe_contextmanager
def fp16_guard():
"""
As for the pure fp16 training, if users set `use_fp16_guard` to True,
only those ops created in the context manager `fp16_guard` will be
transformed as float16 type.
Examples:
.. code-block:: pycon
>>> import numpy as np
>>> import paddle
>>> import paddle.nn.functional as F
>>> paddle.enable_static()
>>> data = paddle.static.data(name='X', shape=[None, 1, 28, 28], dtype='float32')
>>> conv2d = paddle.static.nn.conv2d(input=data, num_filters=6, filter_size=3)
>>> with paddle.static.amp.fp16_guard():
... bn = paddle.static.nn.batch_norm(input=conv2d, act="relu")
... pool = F.max_pool2d(bn, kernel_size=2, stride=2)
... hidden = paddle.static.nn.fc(pool, size=10)
... loss = paddle.mean(hidden)
"""
with framework.name_scope(prefix=_fp16_guard_pattern):
yield
FLOAT_TYPES = {
core.VarDesc.VarType.FP32,
core.VarDesc.VarType.FP16,
core.VarDesc.VarType.BF16,
core.VarDesc.VarType.FP64,
}
SUPPORT_FLOAT_TYPES = {
core.VarDesc.VarType.FP32,
core.VarDesc.VarType.FP16,
core.VarDesc.VarType.BF16,
}
def set_var_dst_dtype(
op, var_names, block, global_block, dtype, need_set_dtype
):
low_precision_var_names = set()
for var_name in var_names:
var = None
try:
var = block._var_recursive(var_name)
except ValueError as e:
_logger.debug(f"-- {e}, try to get it in the global block --")
var = global_block.var(var_name)
if var is not None:
_logger.debug(
f"-- var {var_name} is got in the global block --"
)
if var is None or var.type not in _valid_types:
continue
if var.dtype in FLOAT_TYPES:
low_precision_var_names.add(var_name)
if need_set_dtype:
var.desc.set_dtype(dtype)
_logger.debug(
f"---- op type: {op.type}, var name: {var_name}, var dtype: {var.dtype} ----"
)
return low_precision_var_names
def set_param_dtype(program, dtype, amp_lists, use_fp16_guard, level):
keep_fp32_var_names = set()
if level == "O1" or level == "OD":
return keep_fp32_var_names
all_parameters = []
for block in program.blocks:
all_parameters.extend(block.all_parameters())
ops = block.ops
for op in ops:
# Currently, lookup_table is in black_list and unsupported_list, it's weight will be
# set to fp32 in step 1 of cast_model_tp_fp16. But the weight may be used as matmul's
# input in transformer, so the weight is also in to_fp16_var_names.
# TODO(zhangting2020): consider fix auto_parallel_fp16 and remove lookup_table
# from black_list and unsupported_list.
if op.type in amp_lists.black_list:
continue
if _need_keep_fp32(op, amp_lists.unsupported_list, use_fp16_guard):
for in_name in op.input_names:
keep_fp32_var_names = keep_fp32_var_names.union(
op.input(in_name)
)
else:
for in_name in op.input_names:
if not core.is_compiled_with_ipu() and _keep_fp32_input(
op, in_name
):
keep_fp32_var_names = keep_fp32_var_names.union(
op.input(in_name)
)
for param in all_parameters:
if param.name not in keep_fp32_var_names:
_logger.debug(f"-- set param {param.name} to {dtype} --.")
param.desc.set_dtype(dtype)
return keep_fp32_var_names
def op_need_keep_fp32(op, amp_lists, use_fp16_guard, params_list):
need_keep_fp32 = False
fp16_varname_list_in_fp32_op = set()
if _need_keep_fp32(
op,
amp_lists.unsupported_list,
use_fp16_guard,
):
need_keep_fp32 = True
elif amp_lists.black_varnames is not None and _is_in_black_varnames(
op, amp_lists
):
need_keep_fp32 = True
elif op.type in amp_lists.black_list:
need_keep_fp32 = True
for in_name in op.input_names:
for params in params_list:
if params.name in op.input(in_name):
fp16_varname_list_in_fp32_op = (
fp16_varname_list_in_fp32_op.union([params.name])
)
return need_keep_fp32, fp16_varname_list_in_fp32_op
def get_promote_dtype(op, amp_dtype, block):
dst_dtype = amp_dtype
for in_name in op.input_names:
# for ipu, all inputs must be converted to fp16
if not core.is_compiled_with_ipu() and _keep_fp32_input(op, in_name):
_logger.debug(
f"---- Input {in_name} {op.input(in_name)} should be kept fp32 ----"
)
continue
# if this op has inputs
if in_name:
for in_var_name in op.input(in_name):
in_var = block._find_var_recursive(in_var_name)
if in_var and in_var.dtype == paddle.float32:
dst_dtype = core.VarDesc.VarType.FP32
break
else:
dst_dtype = core.VarDesc.VarType.FP32
return dst_dtype
def get_amp_dst_dtype(
op, amp_dtype, level, block, amp_lists, keep_fp32_ops, keep_fp16_ops
):
if level == 'O2':
return amp_dtype
ops = block.ops
dst_dtype = amp_dtype
if op.type in amp_lists.gray_list:
keep_fp32 = False
keep_fp16 = False
for in_name in op.input_names:
# if this op has inputs
if in_name:
for in_var_name in op.input(in_name):
in_var = block._find_var_recursive(in_var_name)
# this in_var isn't the output of other op
if in_var.op is None:
continue
elif in_var.op is op:
prev_op = find_true_prev_op(ops, op, in_var_name)
if prev_op is None:
continue
else:
prev_op = in_var.op
# if it's one of inputs
if (
prev_op in keep_fp32_ops
or prev_op.type in amp_lists.black_list
):
dst_dtype = core.VarDesc.VarType.FP32
elif (
prev_op in keep_fp16_ops
or prev_op.type in amp_lists.white_list
):
dst_dtype = amp_dtype
else:
# For numerical safe, we apply fp32 computation on ops that
# are not determined which list they should stay.
dst_dtype = core.VarDesc.VarType.FP32
return dst_dtype
def process_op_input_and_outputs(op, block, global_block, dtype):
low_precision_var_names = set()
# Get the FP16 input because the low_precision_var_names is required for the parameter casting.
# The dtype of the input is not set to fp16, because it is done in the step 3 of cast_model_to_fp16.
for in_name in op.input_names:
# for ipu, all inputs must be converted to fp16
if not core.is_compiled_with_ipu() and _keep_fp32_input(op, in_name):
continue
in_vars = set_var_dst_dtype(
op,
op.input(in_name),
block,
global_block,
dtype,
need_set_dtype=False,
)
low_precision_var_names = low_precision_var_names.union(in_vars)
# Set the output to FP16 because its consumer OP needs to determine if the dtype needs
# to be promoted.
for out_name in op.output_names:
# for ipu, all outputs must be converted to fp16
if not core.is_compiled_with_ipu() and _keep_fp32_output(op, out_name):
continue
set_var_dst_dtype(
op,
op.output(out_name),
block,
global_block,
dtype,
need_set_dtype=True,
)
return low_precision_var_names
def map_block(block, fn, parent_op=None):
fn(block, parent_op)
program = block.program
for op in block.ops:
if not op.has_attr("sub_block"):
continue
sub_block = program.blocks[op.attr("sub_block").id]
map_block(sub_block, fn, op)
def prepare_op_amp_options(
program: paddle.static.Program,
amp_records: dict[int, list[tuple[AmpOptions, int, int]]],
global_amp_options: AmpOptions,
):
op_amp_options_map: dict[paddle.static.Operator, AmpOptions] = {}
def fill_amp_enable_op_map(block, parent_op):
block_idx = block.idx
ops = block.ops
for op in ops:
# Set the default options to global_amp_options if the op has not parent op.
current_op_amp_options = op_amp_options_map.get(
parent_op, global_amp_options
)
if block_idx in amp_records:
for amp_options, start, end in amp_records[block_idx]:
if op.idx in range(start, end):
current_op_amp_options = amp_options
break
op_amp_options_map[op] = current_op_amp_options
map_block(program.global_block(), fill_amp_enable_op_map)
for op, enable in op_amp_options_map.items():
op.set_amp_options(enable)
def cast_model_to_fp16(
program,
amp_lists=None,
use_fp16_guard=True,
dest_type=core.VarDesc.VarType.FP16,
level='O2',
use_promote=False,
):
"""
Traverse all ops in the whole model and set their inputs and outputs
to the fp16 data type. This function will do some special process for
the batch normalization, which keeps the computational process of
batchnorms in FP32.
Args:
program (Program): The used program.
amp_lists (AutoMixedPrecisionLists): An AutoMixedPrecisionLists object.
use_fp16_guard(bool): Determine whether to use `fp16_guard` when
constructing the program. Default True.
dest_type(core.VarDesc.VarType): the cast type. such as core.VarDesc.VarType.FP16 and core.VarDesc.VarType.BF16.
"""
_logger.debug("---- before cast model to fp16 ----")
_logger.debug(program)
if amp_lists is None:
dtype = get_low_precision_dtypestr(dest_type)
amp_lists = AutoMixedPrecisionLists(dtype)
# For amp o2 there is no blacklist by default.
if level == 'O2':
amp_lists.black_list = amp_lists.black_list - black_list
if level == 'OD':
if amp_lists is not None:
dtype = get_low_precision_dtypestr(dest_type)
amp_lists = AutoMixedPrecisionLists(dtype)
amp_lists.black_list = amp_lists.all_list - amp_lists.white_list
global_block = program.global_block()
keep_fp32_ops = set()
keep_fp16_ops = set()
to_fp16_var_names = set()
keep_fp32_var_names = set()
# step 1: set params dtype.
fp32_var_names = set_param_dtype(
program,
dtype=dest_type,
amp_lists=amp_lists,
use_fp16_guard=use_fp16_guard,
level=level,
)
keep_fp32_var_names = keep_fp32_var_names.union(fp32_var_names)
def need_process(op):
need_process = True
def is_support_type(name):
if not op.block._find_var_recursive(
name
): # a special case for lod_tensor_blocking_queue_0
return True
if (
op.block._var_recursive(name).type
!= core.VarDesc.VarType.DENSE_TENSOR
):
return False
return op.block._var_recursive(name).dtype in SUPPORT_FLOAT_TYPES
if len(op.input_arg_names) > 0 and all(
not is_support_type(name) for name in op.input_arg_names
):
return False
# if input type of op is fp64, we just skip it.
if op.type in ["set_value"]:
# NOTE(zoooo0820): OP set_value has attribute "dtype", but its output type is
# determined by the input.dtype instead of attribute. So, here we still process it.
return need_process
if op.type in ["create_py_reader", "read"]:
need_process = False
else:
for attr_name in ['out_dtype', 'dtype']:
# output type of some operators such as fill_constant will be determined by the attribute value.
#
if not op.has_attr('in_dtype') and (
op.has_attr(attr_name) and op.attr(attr_name) in FLOAT_TYPES
):
need_process = False
return need_process
# step 2: divide op into different sets according to the black/unsupported and white lists.
for block in program.blocks:
ops = block.ops
for op in ops:
_logger.debug(f"-- process op: {op} --")
if not need_process(op):
_logger.debug("---- The op does not need to be processed ----.")
continue
all_params = global_block.all_parameters()
op_keep_fp32, fp16_var_names_in_fp32_op = op_need_keep_fp32(
op, amp_lists, use_fp16_guard, all_params
)
to_fp16_var_names = to_fp16_var_names.union(
fp16_var_names_in_fp32_op
)
if op_keep_fp32:
keep_fp32_ops.add(op)
process_op_input_and_outputs(
op, block, global_block, core.VarDesc.VarType.FP32
)
_logger.debug(
"---- Add into keep_fp32_ops because the op needs to be kept fp32 ----"
)
elif op.type in amp_lists.white_list:
keep_fp16_ops.add(op)
# get fp16 inputs and set op's outputs to fp16 for promote judgments
fp16_var_names = process_op_input_and_outputs(
op, block, global_block, dest_type
)
to_fp16_var_names = to_fp16_var_names.union(fp16_var_names)
_logger.debug(
"---- Add into keep_fp16_ops because the op in white_list ----"
)
else:
# if cast in origin program, we only modify attr and output's dtype to avoid dtype mismatch errors.
if op.type == 'cast':
in_var = block._find_var_recursive(op.input('X')[0])
out_var = block._find_var_recursive(op.output('Out')[0])
op._set_attr('in_dtype', in_var.dtype)
out_var.desc.set_dtype(paddle.dtype(op.attr('out_dtype')))
_logger.debug(
"---- op type: {}, in var [name: {} dtype: {}], out var [name: {} dtype: {}], attr [in_dtype {} out_dtype {}] ----".format(
op.type,
op.input('X')[0],
in_var.dtype,
op.output('Out')[0],
out_var.dtype,
op.attr('in_dtype'),
op.attr('out_dtype'),
)
)
continue
# divide others ops into fp16/fp32 sets according to promoting principle.
dst_dtype = dest_type
if not use_promote:
dst_dtype = get_amp_dst_dtype(
op,
dest_type,
level,
block,
amp_lists,
keep_fp32_ops,
keep_fp16_ops,
)
else:
dst_dtype = get_promote_dtype(op, dest_type, block)
if dst_dtype == dest_type:
keep_fp16_ops.add(op)
fp16_var_names = process_op_input_and_outputs(
op, block, global_block, dest_type
)
to_fp16_var_names = to_fp16_var_names.union(fp16_var_names)
_logger.debug(
"---- Add into keep_fp16_ops because it should be promoted to fp16 ----"
)
else:
keep_fp32_ops.add(op)
process_op_input_and_outputs(
op, block, global_block, core.VarDesc.VarType.FP32
)
_logger.debug(
"---- Add into keep_fp32_ops because it should be promoted to fp32 ----"
)
# step 3: insert cast op for op's inputs.
for block in program.blocks:
ops = block.ops
idx = 0
while idx < len(ops):
op = ops[idx]
num_cast_ops = 0
if op in keep_fp16_ops:
in_var_cast_num = _insert_cast_op(
block,
op,
idx,
core.VarDesc.VarType.FP32,
dest_type,
)
num_cast_ops += in_var_cast_num
if op in keep_fp32_ops:
in_var_cast_num = _insert_cast_op(
block,
op,
idx,
dest_type,
core.VarDesc.VarType.FP32,
)
num_cast_ops += in_var_cast_num
idx += num_cast_ops + 1
_logger.debug("---- after cast model to fp16 ----")
_logger.debug(program)
to_fp16_var_names.difference_update(keep_fp32_var_names)
return to_fp16_var_names
def _convert_float_to_bfloat16(place, fp32_array):
paddle.disable_static()
framework._set_expected_place(place)
fp32_tensor = paddle.to_tensor(fp32_array)
bf16_array = paddle.cast(fp32_tensor, paddle.bfloat16).numpy()
paddle.enable_static()
return bf16_array
def _convert_to_float(place, org_array):
paddle.disable_static()
framework._set_expected_place(place)
org_tensor = paddle.to_tensor(org_array)
fp32_array = paddle.cast(org_tensor, paddle.float32).numpy()
if in_pir_mode():
fp32_array.get_defining_op().set_bool_attr("master_grad_cast", True)
paddle.enable_static()
return fp32_array
def cast_parameters_to_fp16(
place,
program,
scope=None,
to_fp16_var_names=None,
dest_type=core.VarDesc.VarType.FP16,
rewrite_master_weight=False,
master_weights={},
):
"""
Traverse all parameters in the whole model and set them to the FP16 data type.
Whereas, this function will keep parameters of batchnorms in FP32.
Args:
place(base.CPUPlace|base.CUDAPlace): `place` is used to restore the FP16 weight tensors.
program (Program): The used program.
scope(base.Scope, optional): `scope` is used to get the FP32 weight tensor values.
Default is None.
to_fp16_var_names(set|list, optional): The data types of vars in `to_fp16_var_names`
will be set to FP16. Usually, it is the returned
value of `cast_model_to_fp16` API.
dest_type(core.VarDesc.VarType): the cast type. such as core.VarDesc.VarType.FP16 and core.VarDesc.VarType.BF16.
"""
all_parameters = []
for block in program.blocks:
all_parameters.extend(block.all_parameters())
dtype_str = get_low_precision_dtypestr(dest_type)
fp16_var_names = to_fp16_var_names if to_fp16_var_names else set()
var_scope = scope if scope else global_scope()
for param in all_parameters:
if param.name in fp16_var_names:
_logger.debug(
f"-- cast {param.name} to {dtype_str}, place is {place}"
)
if var_scope.find_var(param.name):
param_t = var_scope.find_var(param.name).get_tensor()
data = np.array(param_t)
if dest_type == paddle.bfloat16:
p_array = _convert_float_to_bfloat16(place, data)
param_t.set(p_array, place)
else:
p_array = np.float16(data)
param_t.set(p_array, place)
# rewrite master weight
if rewrite_master_weight and param.name in master_weights:
master_p_var = var_scope.find_var(
master_weights[param.name].name
)
master_p_t = master_p_var.get_tensor()
master_p_array = _convert_to_float(place, p_array)
master_p_t.set(master_p_array, place)
else:
_logger.warning(f"Cannot find {param.name}")
def update_role_var_grad(main_prog, params_grads):
"""
Update op_role_var attr for some ops to make sure the gradients
transferred across GPUs is FP16.
1. Check whether the op that outputs gradient is cast or not.
2. If op is cast and gradient is FP32, remove the op_role_var
and find the prev op which outputs FP16 gradient
3. Update the op_role_var of the prev op.
Args:
main_prog (Program): The main program for training.
params_grads (list): A list of params and grads.
"""
block = main_prog.global_block()
block._sync_with_cpp()
BACKWARD = core.op_proto_and_checker_maker.OpRole.Backward
OPTIMIZE = core.op_proto_and_checker_maker.OpRole.Optimize
for p, g in params_grads:
op = g.op
if g.dtype == paddle.float32 and op.type == 'cast':
role = op.attr('op_role')
if role & int(BACKWARD) and op.has_attr('op_role_var'):
op._remove_attr("op_role_var")
else:
raise ValueError(
f"The cast op {op} must be in BACKWARD role "
"and have op_role_var attr."
)
fp16_grad_name = op.input(op.input_names[0])[0]
op_for_fp16_grad = find_true_prev_op(block.ops, op, fp16_grad_name)
op_role_var_attr_name = (
core.op_proto_and_checker_maker.kOpRoleVarAttrName()
)
attr_val = [p.name, fp16_grad_name]
if op_for_fp16_grad.has_attr(op_role_var_attr_name):
attr_val.extend(op_for_fp16_grad.attr(op_role_var_attr_name))
op_for_fp16_grad._set_attr(op_role_var_attr_name, attr_val)
# Maximize the all_reduce overlap, and perform the cast
# operation after gradients transfer.
op._set_attr('op_role', OPTIMIZE)
# optimize op should stay behind forward and backward ops
if op == block.ops[-1]:
continue
post_ops = find_true_post_op(block.ops, op, g.name)
if post_ops:
raise ValueError(
f"The cast op {op}'s output should not be"
"used by a non-optimize op, however, it"
f"is used by {post_ops[0]}"
)
# add new op in the python and cpp at the same time
new_op_desc = block.desc.append_op()
new_op_desc.copy_from(op.desc)
new_op = framework.Operator(
block=block,
desc=new_op_desc,
type=None,
inputs=None,
outputs=None,
attrs=None,
)
block.ops.append(new_op)
op_idx = find_op_index(block.desc, op.desc)
if op_idx == -1:
raise ValueError(f"The op {op} is not in program")
block._remove_op(op_idx, sync=False)
block._sync_with_cpp()