fix memory being held by autograd

Author: drisspg

test/dtypes/test_affine_quantized.py

@@ -10,12 +10,33 @@
     int8_dynamic_activation_int8_semi_sparse_weight,
     float8_weight_only,
 )
+from torch.testing._internal import common_utils
 from torchao.utils import TORCH_VERSION_AT_LEAST_2_5
 
 import torch
 import unittest
 import tempfile
 
+is_cuda_8_9 = torch.cuda.is_available() and torch.cuda.get_device_capability() >= (8, 9)
+
+
+def get_quantization_functions(do_sparse: bool, do_int4: bool):
+    base_functions = [
+        int8_weight_only(),
+        int8_dynamic_activation_int4_weight(),
+        int8_dynamic_activation_int8_weight(),
+    ]
+    if do_int4:
+        base_functions.append(int4_weight_only(group_size=32))
+
+    if do_sparse:
+        base_functions.append(int8_dynamic_activation_int8_semi_sparse_weight())
+
+    if is_cuda_8_9:
+        base_functions.append(float8_weight_only())
+
+    return base_functions
+
 
 class TestAffineQuantized(TestCase):
     @unittest.skipIf(not torch.cuda.is_available(), "Need CUDA available")
@@ -38,36 +59,36 @@ def test_tensor_core_layout_transpose(self):
             self.assertEqual(aqt_shape, shape)
 
     @unittest.skipIf(not torch.cuda.is_available(), "Need CUDA available")
-    def test_weights_only(self):
-        for apply_quant in [int4_weight_only(group_size=32), int8_weight_only(), int8_dynamic_activation_int4_weight(),
-                            int8_dynamic_activation_int8_weight(), int8_dynamic_activation_int8_semi_sparse_weight(), float8_weight_only()]:
-            l = torch.nn.Linear(128, 256, dtype=torch.bfloat16, device="cuda")
-            ql = apply_quant(l)
-            with tempfile.NamedTemporaryFile() as f:
-                torch.save(ql.state_dict(), f)
-                f.seek(0)
-                # `weights_only=True` is enabled for torch 2.5+
-                if TORCH_VERSION_AT_LEAST_2_5:
-                    _ = torch.load(f, weights_only=True)
-                else:
-                    _ = torch.load(f, weights_only=False)
+    @common_utils.parametrize("apply_quant", get_quantization_functions(True, True))
+    def test_weights_only(self, apply_quant):
+        l = torch.nn.Linear(128, 256, dtype=torch.bfloat16, device="cuda")
+        ql = apply_quant(l)
+        with tempfile.NamedTemporaryFile() as f:
+            torch.save(ql.state_dict(), f)
+            f.seek(0)
+            # `weights_only=True` is enabled for torch 2.5+
+            if TORCH_VERSION_AT_LEAST_2_5:
+                _ = torch.load(f, weights_only=True)
+            else:
+                _ = torch.load(f, weights_only=False)
 
     @unittest.skipIf(not torch.cuda.is_available(), "Need CUDA available")
-    def test_to_device(self):
-        from torchao.quantization import quantize_
-        for apply_quant in [int8_weight_only(), int8_dynamic_activation_int4_weight(), int8_dynamic_activation_int8_weight()]:
-            l = torch.nn.Linear(128, 256, dtype=torch.bfloat16)
-            ql = apply_quant(l)
-            ql.to("cuda")
+    @common_utils.parametrize("apply_quant", get_quantization_functions(False, False))
+    def test_to_device(self, apply_quant):
+        l = torch.nn.Linear(128, 256, dtype=torch.bfloat16)
+        ql = apply_quant(l)
+        ql.to("cuda")
+
+        l = torch.nn.Linear(128, 256, dtype=torch.bfloat16)
+        ql = apply_quant(l)
+        ql.to(device="cuda")
 
-            l = torch.nn.Linear(128, 256, dtype=torch.bfloat16)
-            ql = apply_quant(l)
-            ql.to(device="cuda")
+        l = torch.nn.Linear(128, 256, dtype=torch.bfloat16)
+        ql = apply_quant(l)
+        ql.cuda()
 
-            l = torch.nn.Linear(128, 256, dtype=torch.bfloat16)
-            ql = apply_quant(l)
-            ql.cuda()
 
+common_utils.instantiate_parametrized_tests(TestAffineQuantized)
 
 if __name__ == "__main__":
     run_tests()

test/dtypes/test_affine_quantized_float.py

@@ -13,10 +13,6 @@
 )
 from torch._inductor.test_case import TestCase as InductorTestCase
 from torch.testing._internal import common_utils
-from torch.testing._internal.common_utils import (
-    TestCase,
-    run_tests,
-)
 from torch._dynamo.testing import CompileCounterWithBackend
 
 from torchao.quantization import (
@@ -54,46 +50,9 @@ def forward(self, x):
         return x
 
 
-class TestAffineQuantizedFloat8Basic(TestCase):
-    @unittest.skipIf(not torch.cuda.is_available(), "Need CUDA available")
-    def test_tensor_core_layout_transpose(self):
-        l = torch.nn.Linear(128, 256, dtype=torch.bfloat16, device="cuda")
-        t = l.weight
-        shape = t.shape
-        apply_float8_weight_only_quant = float8_weight_only()
-        ql = apply_float8_weight_only_quant(l)
-        aqt = ql.weight
-        aqt_shape = aqt.shape
-        assert aqt_shape == shape
-
-        # transpose shape test
-        for _ in range(10):
-            t = t.t()
-            aqt = aqt.t()
-            shape = t.shape
-            aqt_shape = aqt.shape
-            assert aqt_shape == shape
-
-    @unittest.skipIf(not torch.cuda.is_available(), "Need CUDA available")
-    def test_weights_only_save_load(self):
-        with torch.no_grad():
-            for apply_quant in [float8_weight_only()]:
-                # TODO Fails when l requires grad
-                l = torch.nn.Linear(128, 256).eval().to(torch.bfloat16).to("cuda")
-                ql = apply_quant(l)
-                with tempfile.NamedTemporaryFile() as f:
-                    torch.save(ql.state_dict(), f)
-                    f.seek(0)
-                    # `weights_only=True` is enabled for torch 2.5+
-                    if TORCH_VERSION_AT_LEAST_2_5:
-                        _ = torch.load(f, weights_only=True)
-                    else:
-                        _ = torch.load(f, weights_only=False)
-
-
 class TestAffineQuantizedFloat8Compile(InductorTestCase):
     @unittest.skipIf(not torch.cuda.is_available(), "Need CUDA available")
-    @unittest.skipIf(not is_cuda_8_9, "Need H100")
+    @unittest.skipIf(not is_cuda_8_9, "Requires GPU with compute capability >= 8.9")
     @common_utils.parametrize("dtype", [torch.bfloat16, torch.float32])
     @common_utils.parametrize("mode", ["dynamic", "weight-only"])
     @common_utils.parametrize("compile", [True, False])
@@ -108,7 +67,7 @@ class TestAffineQuantizedFloat8Compile(InductorTestCase):
             ((64, 256), 512, 128),
         ],
     )
-    def test_dynamic_fp8_linear(
+    def test_fp8_linear_variants(
         self, dtype: torch.dtype, mode: str, compile: bool, sizes: tuple
     ):
         M, N, K = sizes
@@ -132,7 +91,10 @@ def test_dynamic_fp8_linear(
         output_original = model(input_tensor)
         output_quantized = quantized_model(input_tensor)
 
-        assert compute_error(output_original, output_quantized) > 20, "Error is too low"
+        error = compute_error(output_original, output_quantized)
+        assert (
+            compute_error(output_original, output_quantized) > 20
+        ), f"Quantization error is too high got a SQNR of {error}"
 
 
 common_utils.instantiate_parametrized_tests(TestAffineQuantizedFloat8Compile)

torchao/dtypes/affine_quantized_tensor.py

@@ -214,12 +214,12 @@ def from_hp_to_intx(
         block_size: Tuple[int, ...],
         target_dtype: torch.dtype,
         quant_min: Optional[int] = None,
-        quant_max: Optional[int]  = None,
+        quant_max: Optional[int] = None,
         eps: Optional[float] = None,
         scale_dtype: Optional[torch.dtype] = None,
         zero_point_dtype: Optional[torch.dtype] = None,
         preserve_zero: bool = True,
-        zero_point_domain: ZeroPointDomain = ZeroPointDomain.INT,
+        zero_point_domain: Optional[ZeroPointDomain] = ZeroPointDomain.INT,
         layout_type: LayoutType = PlainLayoutType(),
         use_hqq: bool = False,
     ):
@@ -237,6 +237,9 @@ def from_hp_to_intx(
             data = data.to(target_dtype)
         else:
             scale, zero_point = choose_qparams_affine(input_float, mapping_type, block_size, target_dtype, quant_min, quant_max, eps, scale_dtype, zero_point_dtype, preserve_zero, zero_point_domain)
+            # choose_qparams_affine is a custom op that does support returning optional Tensors. We thus set the zero_point to None if its domain is None
+            if zero_point_domain is None:
+                zero_point = None
             data = quantize_affine(input_float, block_size, scale, zero_point, target_dtype, quant_min, quant_max, zero_point_domain)
             # Note: output will be uint8 tensor for sub byte tensors for now
 
@@ -262,7 +265,7 @@ def from_hp_to_intx_static(
         block_size: Tuple[int, ...],
         target_dtype: torch.dtype,
         quant_min: Optional[int] = None,
-        quant_max: Optional[int]  = None,
+        quant_max: Optional[int] = None,
         zero_point_domain: ZeroPointDomain = ZeroPointDomain.INT,
         layout_type: LayoutType = PlainLayoutType(),
     ):
@@ -291,8 +294,8 @@ def from_hp_to_floatx(
         input_float: torch.Tensor,
         block_size: Tuple[int, ...],
         target_dtype: torch.dtype,
-        scale_dtype: Optional[torch.dtype] = None,
-        layout_type: LayoutType = PlainLayoutType(),
+        scale_dtype: Optional[torch.dtype],
+        layout_type: LayoutType,
     ):
 
         if target_dtype in FP8_TYPES:
@@ -400,10 +403,8 @@ def extra_repr(self):
 
 @dataclass(frozen=True)
 class Float8LayoutType(LayoutType):
-    mm_config: ScaledMMConfig
+    mm_config: Optional[ScaledMMConfig]
 
-    def pre_process(self, input: torch.Tensor) -> torch.Tensor:
-        return input
 
 @register_layout_cls(PlainLayoutType)
 class PlainAQTLayout(AQTLayout):
@@ -602,9 +603,18 @@ def _apply_fn_to_data(self, fn):
         fn(self.scale)
         return self
 
+    def to(self, *args, **kwargs):
+        kwargs = self._get_to_kwargs(*args, **kwargs)
+        return self.__class__(
+            self.float8_data.to(kwargs["device"]),
+            self.scale.to(kwargs["device"]),
+            self.transposed,
+            self.layout_type,
+        )
+
     def __tensor_flatten__(self):
         return ["float8_data", "scale"], [self.transposed, self.layout_type]
-    
+
     @classmethod
     def __tensor_unflatten__(
         cls, tensor_data_dict, tensor_attributes, outer_size, outer_stride
@@ -621,6 +631,10 @@ def __torch_dispatch__(cls, func, types, args, kwargs):
             return return_and_correct_aliasing(
                 func, args, kwargs, args[0]._apply_fn_to_data(torch.detach)
             )
+        if func is aten.clone.default:
+            return return_and_correct_aliasing(
+                func, args, kwargs, args[0]._apply_fn_to_data(torch.clone)
+            )
         if func is aten.t.default:
             """we don't need to repack the weight and just rely on external
             shape being changed and record the status of transpose/no-transpose
@@ -650,6 +664,7 @@ def from_plain(
     ):
         """ Main entrypoint for constructing Float8Layout Tensor"""
         assert _is_float8_type(data.dtype), f"Float8 Layout must be constructed from float8 dtype but got {data.dtype}"
+        assert isinstance(layout_type, Float8LayoutType), f"Float8 Layout must be constructed from Float8LayoutType but got {layout_type}"
         return cls(data, scale, False, layout_type)
 
     def __repr__(self):
@@ -1027,14 +1042,14 @@ def _linear_fp_act_int8_weight_impl(input_tensor, weight_tensor, bias):
 
 
 def _linear_fp_act_fp8_tensor_wise_weight_check(
-    input_tensor: torch.Tensor,
-    weight_tensor: AffineQuantizedTensor,
+    input_tensor: Union[torch.Tensor, AffineQuantizedTensor],
+    weight_tensor: Union[torch.Tensor, AffineQuantizedTensor],
     bias: Optional[torch.Tensor],
 ) -> bool:
-    def check_aqt_tensorwise(aqt: AffineQuantizedTensor) -> bool:
+    def check_aqt_tensorwise(aqt: Union[torch.Tensor, AffineQuantizedTensor]) -> bool:
         return (
             isinstance(aqt, AffineQuantizedTensor) and
-            isinstance(aqt.layout_tensor, Float8AQTLayout)
+            isinstance(aqt.layout_type, Float8LayoutType)
             and aqt.layout_tensor.dtype in [torch.float8_e4m3fn, torch.float8_e5m2]
             and aqt.shape == aqt.block_size
         )
@@ -1047,7 +1062,7 @@ def _linear_fp_act_fp8_weight_impl(
     bias: Optional[torch.Tensor],
 ):
     """Implements matmul between FP8 input and FP8 weight with compute using _scaled_mm"""
-    from torchao.float8.inference import cast_to_float8_e4m3_inference, preprocess_data
+    from torchao.float8.inference import preprocess_data
     from torchao.float8.float8_tensor import ScaledMMConfig
     from torchao.float8.float8_python_api import addmm_float8_unwrapped
 
@@ -1066,7 +1081,7 @@ def _linear_fp_act_fp8_weight_impl(
     # Handle case where input tensor is more than 2D
     inpt_data = inpt_data.reshape(-1, input_tensor.shape[-1])
     input_scale = input_tensor.layout_tensor.scale
-    if input_scale.dim() >= 2:
+    if input_scale.dim() > 2:
         input_scale = input_scale.reshape(-1, input_scale.shape[-1])
 
     inpt_data, w_data = preprocess_data(inpt_data, w_data.T, scaled_mm_config)

torchao/float8/inference.py

@@ -243,10 +243,14 @@ def quantize_to_float8(
         module_filter_fn=module_filter_fn,
     )
 
+
 from torchao.float8.float8_utils import is_row_major, pad_tensor_for_matmul
 
-def preprocess_data(a_data: torch.Tensor, b_data: torch.Tensor, scaled_mm_config: ScaledMMConfig) -> Tuple[torch.Tensor, torch.Tensor]:
-    """ Preprocess the inner fp8 data tensors for admmm
+
+def preprocess_data(
+    a_data: torch.Tensor, b_data: torch.Tensor, scaled_mm_config: ScaledMMConfig
+) -> Tuple[torch.Tensor, torch.Tensor]:
+    """Preprocess the inner fp8 data tensors for admmm
     Args:
         a_data: Input tensor A.
         b_data: Input tensor B.

torchao/quantization/quant_api.py

@@ -493,12 +493,12 @@ def int8_dynamic_activation_int8_semi_sparse_weight():
     return int8_dynamic_activation_int8_weight(layout_type=SemiSparseLayoutType())
 
 
-def float8_weight_only(target_dtype: torch.dtype = torch.float8_e4m3fn):
+def float8_weight_only(weight_dtype: torch.dtype = torch.float8_e4m3fn):
     """
     Applies float8 weight-only symmetric per-channel quantization to linear layers.
     
     Args:
-        target_dtype (torch.dtype): The target data type for weight quantization. Default is torch.float8_e4m3fn.
+        weight_dtype (torch.dtype): The target data type for weight quantization. Default is torch.float8_e4m3fn.
 
     Note:
         The actual matmul will be computed in original precision of the weight tensor.
@@ -511,38 +511,41 @@ def apply_float8wo_quant(weight):
         return to_affine_quantized_floatx(
             input_float=weight,
             block_size=block_size,
-            target_dtype=target_dtype,
+            target_dtype=weight_dtype,
+            scale_dtype=None,
             layout_type=Float8LayoutType(mm_config=None),
         )
 
     return _get_linear_subclass_inserter(apply_float8wo_quant)
 
 
 def float8_dynamic_activation_float8_weight(
-    target_dtype: torch.dtype = torch.float8_e4m3fn,
     activation_dtype: torch.dtype = torch.float8_e4m3fn,
-    mm_config: ScaledMMConfig = ScaledMMConfig(use_fast_accum=True)
+    weight_dtype: torch.dtype = torch.float8_e4m3fn,
+    mm_config: Optional[ScaledMMConfig] = None
 ):
     """
     Applies float8 dynamic symmetric per-tensor quantization to both activations and weights of linear layers.
 
     Args:
-        target_dtype (torch.dtype): The target data type for weight quantization. Default is torch.float8_e4m3fn.
         activation_dtype (torch.dtype): The target data type for activation quantization. Default is torch.float8_e4m3fn.
+        weight_dtype (torch.dtype): The target data type for weight quantization. Default is torch.float8_e4m3fn.
         mm_config (ScaledMMConfig): Configuration for the matrix multiplication. Default uses fast accumulation.
 
     """
-
     from torchao.dtypes import to_affine_quantized_floatx
 
+    if mm_config is None:
+        mm_config = ScaledMMConfig(use_fast_accum=True)
+
     #TODO we are hardcoding TensorWise scaling, will follow up PR for Tensorwise scaling
     def apply_float8_dynamic_activation_quant(weight: torch.Tensor):
         quantized_weight = to_affine_quantized_floatx(
             input_float=weight,
             block_size=weight.shape,
-            target_dtype=target_dtype,
+            target_dtype=weight_dtype,
             scale_dtype=torch.float32,
-            layout_type=Float8LayoutType(mm_config=None),
+            layout_type=Float8LayoutType(mm_config=mm_config),
         )
 
         def input_quant_func(x: torch.Tensor):
@@ -551,7 +554,7 @@ def input_quant_func(x: torch.Tensor):
                 block_size=x.shape,
                 target_dtype=activation_dtype,
                 scale_dtype=torch.float32,
-                layout_type=Float8LayoutType(mm_config=None),
+                layout_type=Float8LayoutType(mm_config=None),  # Config is stored on weight
             )
             return activation