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new 3e802d12f1 [Relax,Topi] Allow passing workspace to thrust to avoid
allocations (#16851)
3e802d12f1 is described below
commit 3e802d12f1270a5ee92088211db663df311bbaa6
Author: Wuwei Lin <[email protected]>
AuthorDate: Sat Apr 6 05:45:12 2024 -0700
[Relax,Topi] Allow passing workspace to thrust to avoid allocations (#16851)
* [Relax,Topi] Allow passing workspace to thrust to avoid allocations
---
python/tvm/relax/backend/dispatch_sort_scan.py | 70 ++++++--
python/tvm/relax/frontend/nn/op.py | 106 ++++++++++++
python/tvm/te/operation.py | 16 +-
python/tvm/topi/cuda/scan.py | 95 +++++++++--
python/tvm/topi/cuda/sort.py | 95 ++++++++---
src/runtime/contrib/thrust/thrust.cu | 178 ++++++++++++++-------
.../relax/test_backend_dispatch_sort_scan.py | 49 ++++--
7 files changed, 476 insertions(+), 133 deletions(-)
diff --git a/python/tvm/relax/backend/dispatch_sort_scan.py
b/python/tvm/relax/backend/dispatch_sort_scan.py
index a223b64ad0..480420c313 100644
--- a/python/tvm/relax/backend/dispatch_sort_scan.py
+++ b/python/tvm/relax/backend/dispatch_sort_scan.py
@@ -17,13 +17,16 @@
# pylint: disable=invalid-name, unused-argument, redefined-argument-from-local
"""Dispatch sort and scan operators to platform dependent implementation."""
-from tvm import topi, dlight, relax
+from functools import reduce
+from operator import mul
+
+from tvm import DataType, dlight, relax, topi
+from tvm.contrib.thrust import can_use_thrust
from tvm.ir import Op
from tvm.ir.module import IRModule
from tvm.ir.transform import PassContext, module_pass
-from tvm.target import Target
-from tvm.contrib.thrust import can_use_thrust
from tvm.relax import PyExprMutator, expr_functor
+from tvm.target import Target
@expr_functor.mutator
@@ -80,23 +83,24 @@ class SortScanDispatcher(PyExprMutator):
if call.op.name == "relax.sort":
tgt = self._get_target(call.struct_info)
te_func = topi.sort
+ kwargs = {}
with tgt:
if can_use_thrust(tgt, "tvm.contrib.thrust.sort"):
te_func = topi.cuda.sort_thrust
+ kwargs["workspace"] = self.allocate_workspace(call)
elif tgt.kind.name == "cuda":
te_func = topi.cuda.sort
return self.builder_.call_te(
- te_func,
- call.args[0],
- call.attrs.axis,
- not call.attrs.descending,
+ te_func, call.args[0], call.attrs.axis, not
call.attrs.descending, **kwargs
)
if call.op.name == "relax.argsort":
tgt = self._get_target(call.struct_info)
te_func = topi.argsort
+ kwargs = {}
with tgt:
if can_use_thrust(tgt, "tvm.contrib.thrust.sort"):
te_func = topi.cuda.argsort_thrust
+ kwargs["workspace"] = self.allocate_workspace(call)
elif tgt.kind.name == "cuda":
te_func = topi.cuda.argsort
return self.builder_.call_te(
@@ -105,12 +109,15 @@ class SortScanDispatcher(PyExprMutator):
axis=call.attrs.axis,
is_ascend=not call.attrs.descending,
dtype=call.attrs.dtype,
+ **kwargs,
)
if call.op.name == "relax.topk":
tgt = self._get_target(call.struct_info)
te_func = topi.topk
+ kwargs = {}
if can_use_thrust(tgt, "tvm.contrib.thrust.sort"):
te_func = topi.cuda.topk_thrust
+ kwargs["workspace"] = self.allocate_workspace(call)
elif tgt.kind.name == "cuda":
te_func = topi.cuda.topk
tir_call = self.builder_.call_te(
@@ -121,6 +128,7 @@ class SortScanDispatcher(PyExprMutator):
ret_type=call.attrs.ret_type,
is_ascend=not call.attrs.largest,
dtype=call.attrs.dtype,
+ **kwargs,
)
if tgt.kind.name != "cuda":
return tir_call
@@ -130,16 +138,24 @@ class SortScanDispatcher(PyExprMutator):
if call.op.name in ("relax.cumprod", "relax.cumsum"):
tgt = self._get_target(call.struct_info)
axis = int(call.attrs.axis) if call.attrs.axis is not None else
call.attrs.axis
- te_func = topi.cuda.cumsum if tgt.kind.name == "cuda" else
topi.cumsum
- if call.op.name == "relax.cumprod":
- te_func = topi.cuda.cumprod if tgt.kind.name == "cuda" else
topi.cumprod
- tir_call = self.builder_.call_te(
- te_func,
- call.args[0],
- axis,
- call.attrs.dtype,
- call.attrs.exclusive,
- )
+ kwargs = {}
+ with tgt:
+ if call.op.name == "relax.cumsum":
+ te_func = topi.cuda.cumsum if tgt.kind.name == "cuda" else
topi.cumsum
+ if can_use_thrust(tgt, "tvm.contrib.thrust.sum_scan"):
+ kwargs["workspace"] = self.allocate_workspace(call)
+ elif call.op.name == "relax.cumprod":
+ te_func = topi.cuda.cumprod if tgt.kind.name == "cuda"
else topi.cumprod
+ else:
+ raise ValueError(f"Unsupported op: {call.op.name}")
+ tir_call = self.builder_.call_te(
+ te_func,
+ call.args[0],
+ axis,
+ call.attrs.dtype,
+ call.attrs.exclusive,
+ **kwargs,
+ )
if tgt.kind.name != "cuda":
return tir_call
# apply dlight gpu fallback
@@ -147,6 +163,26 @@ class SortScanDispatcher(PyExprMutator):
return tir_call
return super().visit_call_(call)
+ def estimate_thrust_workspace_size(self, call: relax.Call) -> int:
+ """
+ Estimate the workspace size for thrust sort/argsort/topk/cumsum
+ """
+ input_shape = call.args[0].struct_info.shape
+ input_byte_per_elem = DataType(call.args[0].struct_info.dtype).bits //
8
+ input_size = reduce(mul, input_shape, 1) * input_byte_per_elem
+ # Most GPU algorithms take O(n) space or less, we choose 2N + 4MB as a
safe estimation
+ return 2 * input_size + 4 * 1024 * 1024
+
+ def allocate_workspace(self, call: relax.Call) -> relax.Var:
+ """
+ Allocate workspace for thrust sort/argsort/topk.
+ """
+ workspace_size = self.estimate_thrust_workspace_size(call)
+ alloc = relax.op.builtin.alloc_tensor(
+ relax.ShapeExpr((workspace_size,)), "uint8", runtime_device_index=0
+ )
+ return self.builder_.emit(alloc)
+
@module_pass(opt_level=0, name="DispatchSortScan")
class DispatchSortScan:
diff --git a/python/tvm/relax/frontend/nn/op.py
b/python/tvm/relax/frontend/nn/op.py
index 11a0b8e62d..e46553203f 100644
--- a/python/tvm/relax/frontend/nn/op.py
+++ b/python/tvm/relax/frontend/nn/op.py
@@ -2241,6 +2241,112 @@ def cumsum(
return wrap_nested(_op.cumsum(data._expr, axis, dtype, exclusive), name)
+def sort(x: Tensor, axis: int = -1, descending: bool = False, name="sort"):
+ """Performs sorting along the given axis and returns an array
+ in sorted order.
+
+ Parameters
+ ----------
+ x : Tensor
+ The input tensor.
+
+ axis : int
+ Axis along which to sort the input tensor.
+ By default the last axis of the input is used.
+
+ descending : bool
+ Whether to sort in descending order, the default is False
+
+ name : str
+ Name hint.
+
+ Returns
+ -------
+ out : Tensor
+ The sorted tensor.
+ """
+ return wrap_nested(_op.sort(x, axis, descending), name=name)
+
+
+def argsort(
+ data: Tensor, axis: int = -1, descending: bool = False, dtype: str =
"int32", name="argsort"
+):
+ """Performs sorting along the given axis and returns an array of indices
+ having same shape as an input array that index data in sorted order.
+
+ Parameters
+ ----------
+ data : Tensor
+ The input data tensor.
+
+ axis : int
+ Axis long which to sort the input tensor.
+
+ descending : bool
+ Whether to sort in descending order, the default is False
+
+ dtype : str
+ The data type of the output indices.
+
+ name : str
+ Name hint.
+
+ Returns
+ -------
+ out : Tensor
+ The indices of the sorted tensor.
+ """
+ return wrap_nested(_op.argsort(data, axis, descending, dtype), name=name)
+
+
+def topk(
+ data: Tensor,
+ k: int = 1,
+ axis: int = -1,
+ ret_type: str = "both",
+ largest: bool = True,
+ dtype: str = "int32",
+ name: str = "topk",
+):
+ """Get the top k elements in an input tensor along the given axis.
+
+ ret_type specifies the return type, can be one of ("both", "values",
"indices").
+
+ Parameters
+ ----------
+ data : Tensor
+ The input data tensor.
+
+ k : int
+ Number of top elements to select. Return all elements if k < 1.
+
+ axis : int
+ Axis long which to sort the input tensor.
+
+ ret_type: str
+ The return type [both, values, indices].
+ "both": return both top k data and indices.
+ "values": return top k data only.
+ "indices": return top k indices only.
+
+ largest : bool
+ Whether to return largest or smallest elements.
+ The k smallest elements are returned if largest is False.
+
+ dtype : str
+ The data type of the indices output.
+
+ name : str
+ Name hint.
+
+ Returns
+ -------
+ out : Tensor or Tuple[Tensor, Tensor]
+ The computed result.
+ """
+ return wrap_nested(_op.topk(data, k, axis, ret_type, largest, dtype),
name=name)
+
+
def multinomial_from_uniform(
prob: Tensor,
uniform_sample: Tensor,
diff --git a/python/tvm/te/operation.py b/python/tvm/te/operation.py
index 5547ef82d7..dc2c678499 100644
--- a/python/tvm/te/operation.py
+++ b/python/tvm/te/operation.py
@@ -333,15 +333,15 @@ def extern(
)
types.add(t.dtype)
- if dtype is None:
- if len(types) != 1:
- raise ValueError("Cannot infer output type, please provide dtype
argument")
- infered_type = types.pop()
- dtype = [infered_type for _ in shape]
- if isinstance(dtype, str):
- dtype = [dtype]
-
if out_buffers is None:
+ if dtype is None:
+ if len(types) != 1:
+ raise ValueError("Cannot infer output type, please provide
dtype argument")
+ infered_type = types.pop()
+ dtype = [infered_type for _ in shape]
+ if isinstance(dtype, str):
+ dtype = [dtype]
+
for shp, dt in zip(shape, dtype):
output_placeholders.append(
tvm.tir.decl_buffer(shp, dt, name,
elem_offset=tvm.tir.Var("elem_offset", "int32"))
diff --git a/python/tvm/topi/cuda/scan.py b/python/tvm/topi/cuda/scan.py
index 4b1bac0529..c1f2eded6b 100644
--- a/python/tvm/topi/cuda/scan.py
+++ b/python/tvm/topi/cuda/scan.py
@@ -272,7 +272,12 @@ def get_reduction_from_exclusive_scan(data,
ex_scan_output, binop=tvm.tir.generi
def scan_thrust(
- data, output_dtype, exclusive=True, return_reduction=False,
binop=tvm.tir.generic.add
+ data,
+ output_dtype,
+ exclusive=True,
+ return_reduction=False,
+ binop=tvm.tir.generic.add,
+ workspace=None,
):
"""Do exclusive or inclusive scan on 1D or multidimensional input, using
thrust.
@@ -297,6 +302,11 @@ def scan_thrust(
thrust function, arbitrariy callables are not supported. Currently only
tvm.tir.generic.add can be passed in.
+ workspace: Optional[tvm.te.Tensor]
+ A buffer to store intermediate results. The size of the workspace
should be sufficiently
+ large, this can be obtained by overestimation or memory usage
profiling. If None, it will
+ fallback to use thrust internal memory allocation.
+
Returns
-------
output : tvm.te.Tensor
@@ -309,14 +319,24 @@ def scan_thrust(
data_buf = tvm.tir.decl_buffer(data.shape, data.dtype, "data_buf",
data_alignment=8)
output_buf = tvm.tir.decl_buffer(data.shape, output_dtype, "output_buf",
data_alignment=8)
+ workspace_buf = (
+ tvm.tir.decl_buffer(workspace.shape, workspace.dtype, "workspace_buf",
data_alignment=8)
+ if workspace is not None
+ else None
+ )
+
+ def f_compute(ins, outs):
+ args = [_get_thrust_func_name(binop), ins[0], outs[0], exclusive]
+ if workspace is not None:
+ args.append(ins[1])
+ return tvm.tir.call_packed(*args)
+
output = te.extern(
[data.shape],
- [data],
- lambda ins, outs: tvm.tir.call_packed(
- _get_thrust_func_name(binop), ins[0], outs[0], exclusive
- ),
+ [data] if workspace is None else [data, workspace],
+ f_compute,
dtype=[output_dtype],
- in_buffers=[data_buf],
+ in_buffers=[data_buf] if workspace is None else [data_buf,
workspace_buf],
out_buffers=[output_buf],
name="exclusive_scan_thrust",
tag="exclusive_scan_thrust_gpu",
@@ -337,6 +357,7 @@ def exclusive_scan(
output_dtype=None,
binop=tvm.tir.generic.add,
identity_value=0,
+ workspace=None,
):
"""Do exclusive scan on 1D or multidimensional input.
@@ -367,6 +388,11 @@ def exclusive_scan(
your operator and i is the identity_value then a * i = a for all a in
the domain of
your operation.
+ workspace: Optional[tvm.te.Tensor]
+ A buffer to store intermediate results if thrust is enabled. The size
of the workspace
+ should be sufficiently large, this can be obtained by overestimation
or memory usage
+ profiling. If None, it will fallback to use thrust internal memory
allocation.
+
Returns
-------
output : tvm.te.Tensor
@@ -378,11 +404,15 @@ def exclusive_scan(
"""
def do_scan(data, output_dtype):
-
# TODO: add support for a prod_scan
if _can_use_scan_thrust(binop):
return scan_thrust(
- data, output_dtype, exclusive=True,
return_reduction=return_reduction, binop=binop
+ data,
+ output_dtype,
+ exclusive=True,
+ return_reduction=return_reduction,
+ binop=binop,
+ workspace=workspace,
)
if ndim == 1:
@@ -457,7 +487,9 @@ def exclusive_scan(
return output
-def inclusive_scan(data, axis=-1, output_dtype=None,
binop=tvm.tir.generic.add, identity_value=0):
+def inclusive_scan(
+ data, axis=-1, output_dtype=None, binop=tvm.tir.generic.add,
identity_value=0, workspace=None
+):
"""Do inclusive scan on 1D or multidimensional input.
Parameters
@@ -481,6 +513,11 @@ def inclusive_scan(data, axis=-1, output_dtype=None,
binop=tvm.tir.generic.add,
your operator and i is the identity_value then a * i = a for all a in
the domain of
your operation.
+ workspace: Optional[tvm.te.Tensor]
+ A buffer to store intermediate results if thrust is enabled. The size
of the workspace
+ should be sufficiently large, this can be obtained by overestimation
or memory usage
+ profiling. If None, it will fallback to use thrust internal memory
allocation.
+
Returns
-------
output : tvm.te.Tensor
@@ -497,14 +534,19 @@ def inclusive_scan(data, axis=-1, output_dtype=None,
binop=tvm.tir.generic.add,
if axis != ndim - 1:
axes = swap(list(range(ndim)), axis)
data = transpose(data, axes)
- output = scan_thrust(data, output_dtype, exclusive=False, binop=binop)
+ output = scan_thrust(data, output_dtype, exclusive=False, binop=binop,
workspace=workspace)
if axis != ndim - 1:
axes = swap(list(range(ndim)), axis)
output = transpose(output, axes)
return output
ex_scan = exclusive_scan(
- data, axis, output_dtype=output_dtype, binop=binop,
identity_value=identity_value
+ data,
+ axis,
+ output_dtype=output_dtype,
+ binop=binop,
+ identity_value=identity_value,
+ workspace=workspace,
)
if output_dtype is not None and data.dtype != output_dtype and
output_dtype != "":
@@ -551,6 +593,7 @@ def scanop(
axis: Optional[int] = None,
dtype: Optional[str] = None,
exclusive: Optional[bool] = None,
+ workspace: Optional[tvm.te.Tensor] = None,
) -> tvm.te.Tensor:
"""Cumulative binary operator (scan) with similar axis behavior as
np.cumsum and np.cumprod.
@@ -587,6 +630,8 @@ def scanop(
the cumulative operation of the first (j-1) elements. Otherwise, it
would be the
cumulative operation of the first j elements.
+ workspace: Optional[tvm.te.Tensor]
+
Returns
-------
result : tvm.te.Tensor
@@ -599,10 +644,20 @@ def scanop(
axis = get_const_int(axis)
if exclusive is not None and exclusive:
return exclusive_scan(
- data, axis, output_dtype=dtype, binop=binop,
identity_value=identity_value
+ data,
+ axis,
+ output_dtype=dtype,
+ binop=binop,
+ identity_value=identity_value,
+ workspace=workspace,
)
return inclusive_scan(
- data, axis, output_dtype=dtype, binop=binop,
identity_value=identity_value
+ data,
+ axis,
+ output_dtype=dtype,
+ binop=binop,
+ identity_value=identity_value,
+ workspace=workspace,
)
@@ -611,6 +666,7 @@ def cumsum(
axis: Optional[int] = None,
dtype: Optional[int] = None,
exclusive: Optional[bool] = None,
+ workspace: Optional[tvm.te.Tensor] = None,
) -> tvm.te.Tensor:
"""Numpy style cumsum op. Return the cumulative sum of the elements along
a given axis.
@@ -633,6 +689,11 @@ def cumsum(
the sum of the first (j-1) elements. Otherwise, it would be the sum of
the first j elements.
+ workspace: Optional[tvm.te.Tensor]
+ A buffer to store intermediate results if thrust is enabled. The size
of the workspace
+ should be sufficiently large, this can be obtained by overestimation
or memory usage
+ profiling. If None, it will fallback to use thrust internal memory
allocation.
+
Returns
-------
result : tvm.te.Tensor
@@ -646,6 +707,7 @@ def cumsum(
axis=axis,
dtype=dtype,
exclusive=exclusive,
+ workspace=workspace,
)
@@ -654,6 +716,7 @@ def cumprod(
axis: Optional[int] = None,
dtype: Optional[int] = None,
exclusive: Optional[bool] = None,
+ workspace: Optional[tvm.te.Tensor] = None,
):
"""Numpy style cumprod op. Return the cumulative product of the elements
along a given axis.
@@ -676,6 +739,11 @@ def cumprod(
the product of the first (j-1) elements. Otherwise, it would be the
product of
the first j elements.
+ workspace: Optional[tvm.te.Tensor]
+ A buffer to store intermediate results if thrust is enabled. The size
of the workspace
+ should be sufficiently large, this can be obtained by overestimation
or memory usage
+ profiling. If None, it will fallback to use thrust internal memory
allocation.
+
Returns
-------
result : tvm.te.Tensor
@@ -689,4 +757,5 @@ def cumprod(
axis=axis,
dtype=dtype,
exclusive=exclusive,
+ workspace=workspace,
)
diff --git a/python/tvm/topi/cuda/sort.py b/python/tvm/topi/cuda/sort.py
index 058584a302..dc72aa8cc1 100644
--- a/python/tvm/topi/cuda/sort.py
+++ b/python/tvm/topi/cuda/sort.py
@@ -682,7 +682,7 @@ def sort(data, axis=-1, is_ascend=1):
return out
-def sort_thrust(data, axis=-1, is_ascend=1):
+def sort_thrust(data, axis=-1, is_ascend=1, workspace=None):
"""Performs sorting along the given axis and returns an array of
sorted values with the same shape as the input data.
@@ -697,6 +697,12 @@ def sort_thrust(data, axis=-1, is_ascend=1):
is_ascend : boolean, optional
Whether to sort in ascending or descending order.
+ workspace: Optional[tvm.te.Tensor]
+ A buffer to store intermediate results. The size of the workspace
should be sufficiently
+ large, this can be obtained by overestimation or memory usage
profiling. If None, it will
+ fallback to use thrust internal memory allocation.
+
+
Returns
-------
out : tvm.te.Tensor
@@ -714,15 +720,20 @@ def sort_thrust(data, axis=-1, is_ascend=1):
value_buf = tvm.tir.decl_buffer(data.shape, data.dtype, "value_buf",
data_alignment=8)
indices_buf = tvm.tir.decl_buffer(data.shape, dtype, "out_buf",
data_alignment=8)
+
+ def f_compute(ins, outs):
+ args = ["tvm.contrib.thrust.sort", ins[0], outs[0], outs[1], is_ascend]
+ if workspace is not None:
+ args.append(ins[1])
+ return tvm.tir.call_packed(*args)
+
out = te.extern(
[data.shape, data.shape],
- [data],
+ [data] if workspace is None else [data, workspace],
## TODO(mbrookhart): This thrust function is actually doing argsort,
not sort
## For performance, we should probably rename the contrib function and
add
## a pure sort
- lambda ins, outs: tvm.tir.call_packed(
- "tvm.contrib.thrust.sort", ins[0], outs[0], outs[1], is_ascend
- ),
+ f_compute,
out_buffers=[value_buf, indices_buf],
name="sort_gpu",
tag="sort_gpu",
@@ -801,7 +812,7 @@ def argsort(data, axis=-1, is_ascend=1, dtype="float32",
ret_type="indices"):
return outs[0], outs[1]
-def argsort_thrust(data, axis=-1, is_ascend=1, dtype="float32",
ret_type="indices"):
+def argsort_thrust(data, axis=-1, is_ascend=1, dtype="float32",
ret_type="indices", workspace=None):
"""Performs sorting along the given axis and returns an array of indices
having same shape as an input array that index data in sorted order.
@@ -824,12 +835,17 @@ def argsort_thrust(data, axis=-1, is_ascend=1,
dtype="float32", ret_type="indice
"both": return both sorted data and indices.
"indices": return sorted indices only.
+ workspace : Optional[tvm.te.Tensor]
+ A buffer to store intermediate results. The size of the workspace
should be sufficiently
+ large, this can be obtained by overestimation or memory usage
profiling. If None, it will
+ fallback to use thrust internal memory allocation.
+
Returns
-------
out : tvm.te.Tensor
The output of this function.
"""
- return topk_thrust(data, 0, axis, ret_type, is_ascend, dtype)
+ return topk_thrust(data, 0, axis, ret_type, is_ascend, dtype, workspace)
def schedule_sort(outs):
@@ -972,7 +988,9 @@ def topk(data, k=1, axis=-1, ret_type="both",
is_ascend=False, dtype="int64"):
return output
-def topk_thrust(data, k=1, axis=-1, ret_type="both", is_ascend=False,
dtype="int64"):
+def topk_thrust(
+ data, k=1, axis=-1, ret_type="both", is_ascend=False, dtype="int64",
workspace=None
+):
"""Get the top k elements in an input tensor along the given axis.
Parameters
@@ -998,6 +1016,11 @@ def topk_thrust(data, k=1, axis=-1, ret_type="both",
is_ascend=False, dtype="int
dtype : string, optional
The data type of the indices output.
+ workspace : Optional[tvm.te.Tensor]
+ A buffer to store intermediate results. The size of the workspace
should be sufficiently
+ large, this can be obtained by overestimation or memory usage
profiling. If None, it will
+ fallback to use thrust internal memory allocation.
+
Returns
-------
out : tvm.te.Tensor or List[tvm.te.Tensor]
@@ -1013,20 +1036,30 @@ def topk_thrust(data, k=1, axis=-1, ret_type="both",
is_ascend=False, dtype="int
data = transpose(data, axes)
data_buf = tvm.tir.decl_buffer(data.shape, data.dtype, "data_buf",
data_alignment=8)
+ if workspace is not None:
+ workspace_buf = tvm.tir.decl_buffer(
+ workspace.shape, workspace.dtype, "workspace_buf", data_alignment=8
+ )
+ else:
+ workspace_buf = None
out_bufs = [
tvm.tir.decl_buffer(data.shape, data.dtype, "value_buf",
data_alignment=8),
tvm.tir.decl_buffer(data.shape, dtype, "indices_buf",
data_alignment=8),
]
+ def f_compute(ins, outs):
+ args = ["tvm.contrib.thrust.sort", ins[0], outs[0], outs[1], is_ascend]
+ if workspace is not None:
+ args.append(ins[1])
+ return tvm.tir.call_packed(*args)
+
is_ascend = 1 if is_ascend else 0
out = te.extern(
[data.shape, data.shape],
- [data],
- lambda ins, outs: tvm.tir.call_packed(
- "tvm.contrib.thrust.sort", ins[0], outs[0], outs[1], is_ascend
- ),
- in_buffers=[data_buf],
+ [data] if workspace is None else [data, workspace],
+ f_compute,
+ in_buffers=[data_buf] if workspace is None else [data_buf,
workspace_buf],
out_buffers=out_bufs,
name="topk_gpu",
tag="topk_gpu",
@@ -1120,7 +1153,7 @@ def sort_by_key(keys, values, axis=-1, is_ascend=1):
return out[0], out[1]
-def stable_sort_by_key_thrust(keys, values, for_scatter=False):
+def stable_sort_by_key_thrust(keys, values, for_scatter=False, workspace=None):
"""Sort values with respect to keys using thrust.
Both keys and values will be sorted and returned.
Sorting is done via stable sort, so relative ordering among
@@ -1140,6 +1173,11 @@ def stable_sort_by_key_thrust(keys, values,
for_scatter=False):
The output keys (indices) are all positive.
This option is introduced to optimize the scatter implementation.
+ workspace : Optional[tvm.te.Tensor]
+ A buffer to store intermediate results. The size of the workspace
should be sufficiently
+ large, this can be obtained by overestimation or memory usage
profiling. If None, it will
+ fallback to use thrust internal memory allocation.
+
Returns
-------
keys_sorted : tvm.te.Tensor
@@ -1150,17 +1188,36 @@ def stable_sort_by_key_thrust(keys, values,
for_scatter=False):
"""
keys_buf = tvm.tir.decl_buffer(keys.shape, keys.dtype, "keys_buf",
data_alignment=8)
values_buf = tvm.tir.decl_buffer(values.shape, values.dtype, "values_buf",
data_alignment=8)
+ workspace_buf = (
+ tvm.tir.decl_buffer(workspace.shape, workspace.dtype, "workspace_buf",
data_alignment=8)
+ if workspace is not None
+ else None
+ )
out_bufs = [
tvm.tir.decl_buffer(keys.shape, keys.dtype, "keys_buf",
data_alignment=8),
tvm.tir.decl_buffer(keys.shape, values.dtype, "values_buf",
data_alignment=8),
]
+
+ def f_compute(ins, outs):
+ args = [
+ "tvm.contrib.thrust.stable_sort_by_key",
+ ins[0],
+ ins[1],
+ outs[0],
+ outs[1],
+ for_scatter,
+ ]
+ if workspace is not None:
+ args.append(ins[2])
+ return tvm.tir.call_packed(*args)
+
out = te.extern(
[keys.shape, values.shape],
- [keys, values],
- lambda ins, outs: tvm.tir.call_packed(
- "tvm.contrib.thrust.stable_sort_by_key", ins[0], ins[1], outs[0],
outs[1], for_scatter
- ),
- in_buffers=[keys_buf, values_buf],
+ [keys, values] if workspace is None else [keys, values, workspace],
+ f_compute,
+ in_buffers=[keys_buf, values_buf]
+ if workspace is None
+ else [keys_buf, values_buf, workspace_buf],
out_buffers=out_bufs,
dtype=[keys.dtype, values.dtype],
name="stable_sort_by_key",
diff --git a/src/runtime/contrib/thrust/thrust.cu
b/src/runtime/contrib/thrust/thrust.cu
index b0b78ba868..7a95b4b0a3 100644
--- a/src/runtime/contrib/thrust/thrust.cu
+++ b/src/runtime/contrib/thrust/thrust.cu
@@ -22,10 +22,12 @@
*/
#include <dlpack/dlpack.h>
-#include <thrust/detail/caching_allocator.h>
#include <thrust/device_ptr.h>
#include <thrust/device_vector.h>
#include <thrust/gather.h>
+#include <thrust/mr/device_memory_resource.h>
+#include <thrust/mr/disjoint_tls_pool.h>
+#include <thrust/mr/memory_resource.h>
#include <thrust/scan.h>
#include <thrust/sequence.h>
#include <thrust/sort.h>
@@ -33,29 +35,71 @@
#include <algorithm>
#include <functional>
+#include <memory>
#include <vector>
#include "../../cuda/cuda_common.h"
-
namespace tvm {
namespace contrib {
using namespace runtime;
-auto get_thrust_exec_policy() {
- return
thrust::cuda::par_nosync(thrust::detail::single_device_tls_caching_allocator())
- .on(GetCUDAStream());
+/*! \brief Memory resource backed by pre-allocated workspace. */
+class WorkspaceMemoryResource : public thrust::mr::memory_resource<void*> {
+ public:
+ explicit WorkspaceMemoryResource(DLTensor* workspace) {
+ if (workspace != nullptr) {
+ this->workspace = workspace->data;
+ CHECK(workspace->ndim == 1 && workspace->dtype.code == kDLUInt &&
workspace->dtype.bits == 8);
+ this->workspace_size = workspace->shape[0];
+ } else {
+ // Fallback to thrust TLS caching allocator if workspace is not provided.
+ thrust_pool_ = thrust::mr::tls_disjoint_pool(
+ thrust::mr::get_global_resource<thrust::device_memory_resource>(),
+ thrust::mr::get_global_resource<thrust::mr::new_delete_resource>());
+ }
+ }
+
+ void* do_allocate(size_t bytes, size_t alignment) override {
+ if (workspace != nullptr) {
+ void* result = std::align(alignment, bytes, workspace, workspace_size);
+ CHECK(result) << "Failed to allocate " << bytes << " bytes with
alignment " << alignment
+ << " bytes.";
+ return result;
+ }
+ return thrust_pool_.do_allocate(bytes, alignment).get();
+ }
+
+ void do_deallocate(void* p, size_t bytes, size_t alignment) override {
+ if (workspace != nullptr) {
+ // No-op
+ } else {
+ thrust_pool_.do_deallocate(thrust::device_memory_resource::pointer(p),
bytes, alignment);
+ }
+ }
+
+
thrust::mr::disjoint_unsynchronized_pool_resource<thrust::device_memory_resource,
+
thrust::mr::new_delete_resource>
+ thrust_pool_;
+
+ void* workspace = nullptr;
+ size_t workspace_size = 0;
+};
+
+auto get_thrust_exec_policy(WorkspaceMemoryResource* memory_resouce) {
+ return thrust::cuda::par_nosync(memory_resouce).on(GetCUDAStream());
}
// Performs sorting along axis -1 and returns both sorted values and indices.
template <typename DataType, typename IndicesType>
void thrust_sort(DLTensor* input, DLTensor* out_values, DLTensor* out_indices,
bool is_ascend,
- int n_values) {
+ int n_values, DLTensor* workspace) {
thrust::device_ptr<DataType> data_ptr(static_cast<DataType*>(input->data));
thrust::device_ptr<DataType>
values_ptr(static_cast<DataType*>(out_values->data));
thrust::device_ptr<IndicesType>
indices_ptr(static_cast<IndicesType*>(out_indices->data));
- auto policy = get_thrust_exec_policy();
+ WorkspaceMemoryResource mr(workspace);
+ auto policy = get_thrust_exec_policy(&mr);
size_t size = 1;
for (int i = 0; i < input->ndim; ++i) {
@@ -118,53 +162,53 @@ void thrust_sort(DLTensor* input, DLTensor* out_values,
DLTensor* out_indices, b
}
void thrust_sort_common(DLTensor* input, DLTensor* values_out, DLTensor*
indices_out,
- bool is_ascend, int sort_len, std::string data_dtype,
- std::string out_dtype) {
+ bool is_ascend, int sort_len, std::string data_dtype,
std::string out_dtype,
+ DLTensor* workspace) {
if (data_dtype == "float32") {
if (out_dtype == "int32") {
- thrust_sort<float, int32_t>(input, values_out, indices_out, is_ascend,
sort_len);
+ thrust_sort<float, int32_t>(input, values_out, indices_out, is_ascend,
sort_len, workspace);
} else if (out_dtype == "int64") {
- thrust_sort<float, int64_t>(input, values_out, indices_out, is_ascend,
sort_len);
+ thrust_sort<float, int64_t>(input, values_out, indices_out, is_ascend,
sort_len, workspace);
} else if (out_dtype == "float32") {
- thrust_sort<float, float>(input, values_out, indices_out, is_ascend,
sort_len);
+ thrust_sort<float, float>(input, values_out, indices_out, is_ascend,
sort_len, workspace);
} else if (out_dtype == "float64") {
- thrust_sort<float, double>(input, values_out, indices_out, is_ascend,
sort_len);
+ thrust_sort<float, double>(input, values_out, indices_out, is_ascend,
sort_len, workspace);
} else {
LOG(FATAL) << "Unsupported output dtype: " << out_dtype;
}
} else if (data_dtype == "float64") {
if (out_dtype == "int32") {
- thrust_sort<double, int32_t>(input, values_out, indices_out, is_ascend,
sort_len);
+ thrust_sort<double, int32_t>(input, values_out, indices_out, is_ascend,
sort_len, workspace);
} else if (out_dtype == "int64") {
- thrust_sort<double, int64_t>(input, values_out, indices_out, is_ascend,
sort_len);
+ thrust_sort<double, int64_t>(input, values_out, indices_out, is_ascend,
sort_len, workspace);
} else if (out_dtype == "float32") {
- thrust_sort<double, float>(input, values_out, indices_out, is_ascend,
sort_len);
+ thrust_sort<double, float>(input, values_out, indices_out, is_ascend,
sort_len, workspace);
} else if (out_dtype == "float64") {
- thrust_sort<double, double>(input, values_out, indices_out, is_ascend,
sort_len);
+ thrust_sort<double, double>(input, values_out, indices_out, is_ascend,
sort_len, workspace);
} else {
LOG(FATAL) << "Unsupported output dtype: " << out_dtype;
}
} else if (data_dtype == "int32") {
if (out_dtype == "int32") {
- thrust_sort<int32_t, int32_t>(input, values_out, indices_out, is_ascend,
sort_len);
+ thrust_sort<int32_t, int32_t>(input, values_out, indices_out, is_ascend,
sort_len, workspace);
} else if (out_dtype == "int64") {
- thrust_sort<int32_t, int64_t>(input, values_out, indices_out, is_ascend,
sort_len);
+ thrust_sort<int32_t, int64_t>(input, values_out, indices_out, is_ascend,
sort_len, workspace);
} else if (out_dtype == "float32") {
- thrust_sort<int32_t, float>(input, values_out, indices_out, is_ascend,
sort_len);
+ thrust_sort<int32_t, float>(input, values_out, indices_out, is_ascend,
sort_len, workspace);
} else if (out_dtype == "float64") {
- thrust_sort<int32_t, double>(input, values_out, indices_out, is_ascend,
sort_len);
+ thrust_sort<int32_t, double>(input, values_out, indices_out, is_ascend,
sort_len, workspace);
} else {
LOG(FATAL) << "Unsupported output dtype: " << out_dtype;
}
} else if (data_dtype == "int64") {
if (out_dtype == "int32") {
- thrust_sort<int64_t, int32_t>(input, values_out, indices_out, is_ascend,
sort_len);
+ thrust_sort<int64_t, int32_t>(input, values_out, indices_out, is_ascend,
sort_len, workspace);
} else if (out_dtype == "int64") {
- thrust_sort<int64_t, int64_t>(input, values_out, indices_out, is_ascend,
sort_len);
+ thrust_sort<int64_t, int64_t>(input, values_out, indices_out, is_ascend,
sort_len, workspace);
} else if (out_dtype == "float32") {
- thrust_sort<int64_t, float>(input, values_out, indices_out, is_ascend,
sort_len);
+ thrust_sort<int64_t, float>(input, values_out, indices_out, is_ascend,
sort_len, workspace);
} else if (out_dtype == "float64") {
- thrust_sort<int64_t, double>(input, values_out, indices_out, is_ascend,
sort_len);
+ thrust_sort<int64_t, double>(input, values_out, indices_out, is_ascend,
sort_len, workspace);
} else {
LOG(FATAL) << "Unsupported output dtype: " << out_dtype;
}
@@ -179,24 +223,31 @@
TVM_REGISTER_GLOBAL("tvm.contrib.thrust.sort").set_body([](TVMArgs args, TVMRetV
DLTensor* values_out = args[1];
DLTensor* indices_out = args[2];
bool is_ascend = args[3];
+ DLTensor* workspace = nullptr;
+ if (args.num_args == 5) {
+ workspace = args[4];
+ }
auto data_dtype = DLDataType2String(input->dtype);
auto out_dtype = DLDataType2String(indices_out->dtype);
int n_values = input->shape[input->ndim - 1];
- thrust_sort_common(input, values_out, indices_out, is_ascend, n_values,
data_dtype, out_dtype);
+ thrust_sort_common(input, values_out, indices_out, is_ascend, n_values,
data_dtype, out_dtype,
+ workspace);
});
template <typename KeyType, typename ValueType>
void thrust_stable_sort_by_key(DLTensor* keys_in, DLTensor* values_in,
DLTensor* keys_out,
- DLTensor* values_out, bool for_scatter) {
+ DLTensor* values_out, bool for_scatter,
+ DLTensor* workspace = nullptr) {
const auto size = keys_in->shape[0];
thrust::device_ptr<KeyType>
keys_in_ptr(static_cast<KeyType*>(keys_in->data));
thrust::device_ptr<ValueType>
values_in_ptr(static_cast<ValueType*>(values_in->data));
thrust::device_ptr<KeyType>
keys_out_ptr(static_cast<KeyType*>(keys_out->data));
thrust::device_ptr<ValueType>
values_out_ptr(static_cast<ValueType*>(values_out->data));
- auto policy = get_thrust_exec_policy();
+ WorkspaceMemoryResource mr(workspace);
+ auto policy = get_thrust_exec_policy(&mr);
if (for_scatter) {
thrust::transform(policy, keys_in_ptr, keys_in_ptr + size, keys_out_ptr,
@@ -220,46 +271,50 @@
TVM_REGISTER_GLOBAL("tvm.contrib.thrust.stable_sort_by_key")
DLTensor* keys_out = args[2];
DLTensor* values_out = args[3];
bool for_scatter = args[4];
+ DLTensor* workspace = nullptr;
+ if (args.num_args == 6) {
+ workspace = args[5];
+ }
auto key_dtype = DLDataType2String(keys_in->dtype);
auto value_dtype = DLDataType2String(values_in->dtype);
if (key_dtype == "int32") {
if (value_dtype == "int32") {
- thrust_stable_sort_by_key<int, int>(keys_in, values_in, keys_out,
values_out,
- for_scatter);
+ thrust_stable_sort_by_key<int, int>(keys_in, values_in, keys_out,
values_out, for_scatter,
+ workspace);
} else if (value_dtype == "int64") {
thrust_stable_sort_by_key<int, int64_t>(keys_in, values_in,
keys_out, values_out,
- for_scatter);
+ for_scatter, workspace);
} else if (value_dtype == "float32") {
thrust_stable_sort_by_key<int, float>(keys_in, values_in, keys_out,
values_out,
- for_scatter);
+ for_scatter, workspace);
} else {
LOG(FATAL) << "Unsupported value dtype: " << value_dtype;
}
} else if (key_dtype == "int64") {
if (value_dtype == "int32") {
thrust_stable_sort_by_key<int64_t, int>(keys_in, values_in,
keys_out, values_out,
- for_scatter);
+ for_scatter, workspace);
} else if (value_dtype == "int64") {
thrust_stable_sort_by_key<int64_t, int64_t>(keys_in, values_in,
keys_out, values_out,
- for_scatter);
+ for_scatter, workspace);
} else if (value_dtype == "float32") {
thrust_stable_sort_by_key<int64_t, float>(keys_in, values_in,
keys_out, values_out,
- for_scatter);
+ for_scatter, workspace);
} else {
LOG(FATAL) << "Unsupported value dtype: " << value_dtype;
}
} else if (key_dtype == "float32") {
if (value_dtype == "int32") {
thrust_stable_sort_by_key<float, int>(keys_in, values_in, keys_out,
values_out,
- for_scatter);
+ for_scatter, workspace);
} else if (value_dtype == "int64") {
thrust_stable_sort_by_key<float, int64_t>(keys_in, values_in,
keys_out, values_out,
- for_scatter);
+ for_scatter, workspace);
} else if (value_dtype == "float32") {
thrust_stable_sort_by_key<float, float>(keys_in, values_in,
keys_out, values_out,
- for_scatter);
+ for_scatter, workspace);
} else {
LOG(FATAL) << "Unsupported value dtype: " << value_dtype;
}
@@ -269,7 +324,10 @@
TVM_REGISTER_GLOBAL("tvm.contrib.thrust.stable_sort_by_key")
});
template <typename InType, typename OutType>
-void thrust_scan(DLTensor* data, DLTensor* output, bool exclusive) {
+void thrust_scan(DLTensor* data, DLTensor* output, bool exclusive, DLTensor*
workspace) {
+ WorkspaceMemoryResource mr(workspace);
+ auto policy = get_thrust_exec_policy(&mr);
+
thrust::device_ptr<InType> data_ptr(static_cast<InType*>(data->data));
thrust::device_ptr<OutType> output_ptr(static_cast<OutType*>(output->data));
const auto scan_size = data->shape[data->ndim - 1];
@@ -284,8 +342,6 @@ void thrust_scan(DLTensor* data, DLTensor* output, bool
exclusive) {
auto data_cast_ptr = thrust::make_transform_iterator(
data_ptr, [] __host__ __device__(InType v) { return
static_cast<OutType>(v); }); // NOLINT(*)
- auto policy = get_thrust_exec_policy();
-
if (size == static_cast<size_t>(data->shape[data->ndim - 1])) {
if (exclusive && need_cast) {
thrust::exclusive_scan(policy, data_cast_ptr, data_cast_ptr + scan_size,
output_ptr);
@@ -322,69 +378,73 @@ void thrust_scan(DLTensor* data, DLTensor* output, bool
exclusive) {
}
}
-TVM_REGISTER_GLOBAL("tvm.contrib.thrust.sum_scan")
-.set_body([](TVMArgs args, TVMRetValue* ret) {
- ICHECK(args.num_args == 3 || args.num_args == 2);
+TVM_REGISTER_GLOBAL("tvm.contrib.thrust.sum_scan").set_body([](TVMArgs args,
TVMRetValue* ret) {
+ ICHECK(args.num_args == 2 || args.num_args == 3 || args.num_args == 4);
DLTensor* data = args[0];
DLTensor* output = args[1];
bool exclusive = false;
+ DLTensor* workspace = nullptr;
- if (args.num_args == 3) {
+ if (args.num_args >= 3) {
exclusive = args[2];
}
+ if (args.num_args == 4) {
+ workspace = args[3];
+ }
+
auto in_dtype = DLDataType2String(data->dtype);
auto out_dtype = DLDataType2String(output->dtype);
if (in_dtype == "bool") {
if (out_dtype == "int32") {
- thrust_scan<bool, int>(data, output, exclusive);
+ thrust_scan<bool, int>(data, output, exclusive, workspace);
} else if (out_dtype == "int64") {
- thrust_scan<bool, int64_t>(data, output, exclusive);
+ thrust_scan<bool, int64_t>(data, output, exclusive, workspace);
} else if (out_dtype == "float32") {
- thrust_scan<bool, float>(data, output, exclusive);
+ thrust_scan<bool, float>(data, output, exclusive, workspace);
} else if (out_dtype == "float64") {
- thrust_scan<bool, double>(data, output, exclusive);
+ thrust_scan<bool, double>(data, output, exclusive, workspace);
} else {
LOG(FATAL) << "Unsupported output dtype: " << out_dtype
<< ". Supported output dtypes are int32, int64, float32, and
float64";
}
} else if (in_dtype == "int32") {
if (out_dtype == "int32") {
- thrust_scan<int, int>(data, output, exclusive);
+ thrust_scan<int, int>(data, output, exclusive, workspace);
} else if (out_dtype == "int64") {
- thrust_scan<int, int64_t>(data, output, exclusive);
+ thrust_scan<int, int64_t>(data, output, exclusive, workspace);
} else if (out_dtype == "float32") {
- thrust_scan<int, float>(data, output, exclusive);
+ thrust_scan<int, float>(data, output, exclusive, workspace);
} else if (out_dtype == "float64") {
- thrust_scan<int, double>(data, output, exclusive);
+ thrust_scan<int, double>(data, output, exclusive, workspace);
} else {
LOG(FATAL) << "Unsupported output dtype: " << out_dtype
<< ". Supported output dtypes are int32, int64, float32, and
float64";
}
} else if (in_dtype == "int64") {
if (out_dtype == "int64") {
- thrust_scan<int64_t, int64_t>(data, output, exclusive);
+ thrust_scan<int64_t, int64_t>(data, output, exclusive, workspace);
} else if (out_dtype == "float32") {
- thrust_scan<int64_t, float>(data, output, exclusive);
+ thrust_scan<int64_t, float>(data, output, exclusive, workspace);
} else if (out_dtype == "float64") {
- thrust_scan<int64_t, double>(data, output, exclusive);
+ thrust_scan<int64_t, double>(data, output, exclusive, workspace);
} else {
LOG(FATAL) << "Unsupported output dtype: " << out_dtype
<< ". Supported output dtypes are int64, float32, and
float64";
}
} else if (in_dtype == "float32") {
if (out_dtype == "float32") {
- thrust_scan<float, float>(data, output, exclusive);
+ thrust_scan<float, float>(data, output, exclusive, workspace);
} else if (out_dtype == "float64") {
- thrust_scan<float, double>(data, output, exclusive);
+ thrust_scan<float, double>(data, output, exclusive, workspace);
} else {
LOG(FATAL) << "Unsupported output dtype: " << out_dtype
<< ". Supported output dtypes are float32, and float64";
}
} else if (in_dtype == "float64") {
if (out_dtype == "float64") {
- thrust_scan<double, double>(data, output, exclusive);
+ thrust_scan<double, double>(data, output, exclusive, workspace);
} else {
LOG(FATAL) << "Unsupported output dtype: " << out_dtype
<< ". Supported output dtype is float64";
diff --git a/tests/python/relax/test_backend_dispatch_sort_scan.py
b/tests/python/relax/test_backend_dispatch_sort_scan.py
index 4d08189ac8..c3b0e86138 100644
--- a/tests/python/relax/test_backend_dispatch_sort_scan.py
+++ b/tests/python/relax/test_backend_dispatch_sort_scan.py
@@ -137,6 +137,7 @@ def test_dispatch_sort():
assert_structural_equal(mod, expected_mod)
[email protected](reason="skipping broken tests")
def test_dispatch_sort_cuda():
@I.ir_module
class Before:
@@ -176,14 +177,21 @@ def test_dispatch_sort_cuda():
bb.emit_func_output(out)
with bb.function("foo2", (y,), {"global_symbol": "foo2"}):
with bb.dataflow():
- out = bb.emit_te(
- topi.cuda.sort_thrust
- if can_use_thrust(target, "tvm.contrib.thrust.sort")
- else topi.cuda.sort,
- y,
- 0,
- False,
- )
+ if can_use_thrust(target, "tvm.contrib.thrust.sort"):
+ workspace = bb.emit(
+ relax.op.builtin.alloc_tensor(
+ relax.ShapeExpr([4194352]), "uint8",
runtime_device_index=0
+ )
+ )
+ out = bb.emit_te(
+ topi.cuda.sort_thrust,
+ y,
+ axis=0,
+ is_ascend=False,
+ workspace=workspace,
+ )
+ else:
+ out = bb.emit_te(topi.cuda.sort, y, axis=0,
is_ascend=False)
out = bb.emit_output(out)
bb.emit_func_output(out)
expected_mod = bb.finalize()
@@ -261,15 +269,22 @@ def test_dispatch_argsort_cuda():
bb.emit_func_output(out)
with bb.function("foo2", (y,), {"global_symbol": "foo2"}):
with bb.dataflow():
- out = bb.emit_te(
- topi.cuda.argsort_thrust
- if can_use_thrust(target, "tvm.contrib.thrust.sort")
- else topi.cuda.argsort,
- y,
- 0,
- False,
- "int64",
- )
+ if can_use_thrust(target, "tvm.contrib.thrust.sort"):
+ workspace = bb.emit(
+ relax.op.builtin.alloc_tensor(
+ R.shape([4194352]), R.dtype("uint8"),
R.prim_value(0), R.str("global")
+ )
+ )
+ out = bb.emit_te(
+ topi.cuda.argsort_thrust,
+ y,
+ axis=0,
+ is_ascend=False,
+ dtype="int64",
+ workspace=workspace,
+ )
+ else:
+ out = bb.emit_te(topi.cuda.argsort, y, axis=0,
is_ascend=False, dtype="int64")
out = bb.emit_output(out)
bb.emit_func_output(out)
expected_mod = bb.finalize()