[FRONTEND] Significantly reduce kernel launch time (#367)

This commit is contained in:
Philippe Tillet
2021-11-04 13:25:24 -07:00
committed by GitHub
parent 2acaa4d0dd
commit 5d54352164
4 changed files with 245 additions and 124 deletions

View File

@@ -127,7 +127,7 @@ setup(
description="A language and compiler for custom Deep Learning operations",
long_description="",
packages=["triton", "triton/_C", "triton/language", "triton/tools", "triton/ops", "triton/ops/blocksparse"],
install_requires=["torch", "filelock"],
install_requires=["cmake", "torch", "filelock"],
package_data={"triton/ops": ["*.c"], "triton/ops/blocksparse": ["*.c"]},
include_package_data=True,
ext_modules=[CMakeExtension("triton", "triton/_C/")],

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@@ -13,6 +13,7 @@
#include <pybind11/functional.h>
#include <pybind11/pybind11.h>
#include <pybind11/stl.h>
#include "Python.h"
#include <regex>
#include <string>
#include "llvm/IR/Module.h"
@@ -23,6 +24,7 @@ namespace py = pybind11;
namespace ir = triton::ir;
namespace drv = triton::driver;
/*****************************************************************************/
/* Python bindings for triton::driver */
/*****************************************************************************/
@@ -99,8 +101,113 @@ void hip_enqueue(uint64_t stream, uint64_t kernel,
}
std::string pow2_divisor(long N){
if(N % 16 == 0) return "16";
if(N % 8 == 0) return "8";
if(N % 4 == 0) return "4";
if(N % 2 == 0) return "2";
return "1";
}
// Launch
void parse_args(py::handle& args, const std::string& func_key, py::handle& arg_names,
std::string& cache_key, std::string& params, size_t& params_size, PyObject* constants,
int num_warps, int num_stages) {
size_t len = PyList_Size(args.ptr());
params.reserve(8*len); // 8 max bytes by argument
char* params_ptr = &params[0];
cache_key = func_key;
for(int i = 0; i < len; i++){
auto arg_ptr = PyList_GetItem(args.ptr(), i);
auto arg = py::handle(arg_ptr);
// argument is `long`
if(PyLong_Check(arg_ptr)){
int overflow;
long long value = PyLong_AsLongLongAndOverflow(arg_ptr, &overflow);
// long and int have different kernels
if(!overflow & (std::abs(value) <= 0xffffffff)){
cache_key += 'I';
params_ptr = (char*)(((uintptr_t)params_ptr + 3) & (-4));
std::memcpy(params_ptr, &value, 4);
params_ptr += 4;
}
else{
cache_key += 'L';
params_ptr = (char*)(((uintptr_t)params_ptr + 7) & (-8));
if(overflow){
unsigned long long uvalue = PyLong_AsUnsignedLongLong(arg_ptr);
std::memcpy(&value, &uvalue, 8);
}
std::memcpy(params_ptr, &value, 8);
params_ptr += 8;
}
// values equal to 1 are specialized
if(value == 1)
cache_key += '1';
else
cache_key += 'x';
// values divisible by small powers of 2 are specialized
cache_key += pow2_divisor(value);
continue;
}
// argument is `float`
if(PyFloat_Check(arg_ptr)){
cache_key += "f";
float value = PyFloat_AsDouble(arg_ptr);
params_ptr = (char*)(((uintptr_t)params_ptr + 3) & (-4));
std::memcpy(params_ptr, &value, 4);
params_ptr += 4;
continue;
}
// argument is `bool`
if(PyBool_Check(arg_ptr)){
cache_key += "B";
bool value = arg_ptr == Py_True ? true : false;
std::memcpy(params_ptr, &value, 1);
params_ptr += 1;
continue;
}
// argument is tensor
PyObject* data_ptr = PyObject_CallMethod(arg_ptr, "data_ptr", nullptr);
if(data_ptr){
cache_key += "P";
long value = PyLong_AsLong(data_ptr);
params_ptr = (char*)(((uintptr_t)params_ptr + 7) & (-8));
std::memcpy(params_ptr, &value, 8);
params_ptr += 8;
PyObject* dtype = PyObject_GetAttrString(arg_ptr, "dtype");
PyObject* repr = PyObject_Repr(dtype);
const char* start = (const char*)PyUnicode_1BYTE_DATA(repr) + 6; // remove 'torch.'
size_t len = PyUnicode_GET_LENGTH(repr) - 6;
cache_key += std::string(start, len);
continue;
}
// argument is `constexpr`
PyObject* value = PyObject_GetAttrString(arg_ptr, "value");
if(value){
PyObject* name = PyList_GetItem(arg_names.ptr(), i);
PyDict_SetItem(constants, name, value);
PyObject* repr = PyObject_Repr(value);
const char* start = (const char*)PyUnicode_1BYTE_DATA(repr);
size_t len = PyUnicode_GET_LENGTH(repr);
cache_key += std::string(start, len);
continue;
}
assert(false);
}
cache_key += std::to_string(num_warps);
cache_key += std::to_string(num_stages);
params_size = (std::ptrdiff_t)(params_ptr - &params[0]);
}
//
void init_triton_runtime(py::module &&m) {
// m.def("current_stream", [](uint64_t device){
// return (uint64_t)(c10::cuda::getCurrentCUDAStream(device).stream());
// });
// wrap backend_t
py::enum_<backend_t>(m, "backend")
.value("HOST", HOST)
@@ -116,6 +223,51 @@ void init_triton_runtime(py::module &&m) {
}
);
// cache key
m.def("launch", [](py::handle args, const std::string& func_key, py::list& arg_names,
py::handle device, py::handle stream, py::handle bin_cache, py::handle num_warps, py::handle num_stages,
py::handle add_to_cache, py::handle grid){
// parse arguments to compute cache key, compile-time constants and packed kernel arguments
long _num_warps = PyLong_AsLong(num_warps.ptr());
long _num_stages = PyLong_AsLong(num_stages.ptr());
std::string cache_key;
std::string params;
size_t params_size;
PyObject* constants = PyDict_New();
parse_args(args, func_key, arg_names, cache_key, params, params_size, constants, _num_warps, _num_stages);
// get cached binary
PyObject* key = PyUnicode_FromString(cache_key.c_str());
PyObject* bin = nullptr;
if(!PyDict_Contains(bin_cache.ptr(), key)){
add_to_cache(py::handle(key), args, device, num_warps, num_stages);
}
bin = PyDict_GetItem(bin_cache.ptr(), key);
// get grid
PyObject* grid_ptr = grid.ptr();
if(!PySequence_Check(grid_ptr)){
PyObject* grid_call = PyObject_GetAttrString(grid_ptr, "__call__");
grid_ptr = PyObject_Call(grid_call, PyTuple_Pack(1, constants), nullptr);
}
int size = PySequence_Size(grid_ptr);
int grid_0 = PyLong_AsLong(PySequence_GetItem(grid_ptr, 0));
int grid_1 = size < 2 ? 1 : PyLong_AsLong(PySequence_GetItem(grid_ptr, 1));
int grid_2 = size < 3 ? 1 : PyLong_AsLong(PySequence_GetItem(grid_ptr, 2));
// enqueue
uint64_t kernel = PyLong_AsLong(PyObject_GetAttrString(bin, "kernel"));
uint64_t shared_mem = PyLong_AsLong(PyObject_GetAttrString(bin, "shared_mem"));
// actually launch
void *config[] = {
CU_LAUNCH_PARAM_BUFFER_POINTER, params.data(),
CU_LAUNCH_PARAM_BUFFER_SIZE, &params_size,
CU_LAUNCH_PARAM_END
};
uint64_t _stream = PyLong_AsLong(stream.ptr());
drv::dispatch::cuLaunchKernel((CUfunction)kernel, grid_0, grid_1, grid_2,
_num_warps*32, 1, 1, shared_mem, (CUstream)_stream,
nullptr, config);
return py::handle(bin);
});
// query maximum shared memory
m.def("max_shared_memory", [](backend_t backend, uint64_t device) {
if (backend == HOST)

View File

@@ -464,6 +464,7 @@ class LoadedBinary:
self.module = module
self.kernel = kernel
self.device = device
self.shared_mem = bin.shared_mem
def __call__(self, stream, args, grid_0, grid_1=1, grid_2=1):
_triton.runtime.enqueue(self.bin.backend, stream, self.kernel,
@@ -548,16 +549,6 @@ class Kernel:
name = Kernel._type_name(obj)
return type_map[name](context)
@staticmethod
def _types_key(*wargs, tensor_idxs):
# type inference
types_key = [None] * len(wargs)
for i, arg in enumerate(wargs):
prefix = 'P' if i in tensor_idxs else ''
suffix = Kernel._type_name(arg) if i in tensor_idxs else Kernel._type_name(arg)
types_key[i] = prefix + suffix
return tuple(types_key)
@staticmethod
def pow2_divisor(N):
if N % 16 == 0: return 16
@@ -599,6 +590,53 @@ class Kernel:
raise OutOfResources(shared_mem, max_shared_memory, "shared memory")
return Binary(backend, name, asm, shared_mem, num_warps)
def add_to_cache(self, key, wargs, device_idx, num_warps, num_stages):
tensor_idxs = [i for i, arg in enumerate(wargs) if hasattr(arg, 'data_ptr')]
# attributes
args = [arg.data_ptr() if i in tensor_idxs else arg for i, arg in enumerate(wargs)]
attributes = {i: Kernel.pow2_divisor(a) for i, a in enumerate(args) \
if isinstance(a, int) and i not in self.fn.do_not_specialize}
# transforms ints whose value is one into constants for just-in-time compilation
constants = {i: arg for i, arg in enumerate(wargs) if isinstance(arg, int) and arg == 1}
constants.update({i: arg.value for i, arg in enumerate(wargs) if isinstance(arg, triton.language.constexpr)})
hashed_key = hashlib.md5(key.encode("utf-8")).hexdigest()
# create cache directory
cache_dir = os.environ.get('TRITON_CACHE_DIR', '/tmp/triton/')
if cache_dir and not os.path.exists(cache_dir):
os.makedirs(cache_dir, exist_ok=True)
if cache_dir:
bin_cache_path = os.path.join(cache_dir, hashed_key)
bin_lock_path = bin_cache_path + ".lock"
else:
bin_cache_path = None
bin_lock_path = None
binary = None
if bin_cache_path and os.path.exists(bin_cache_path):
assert bin_lock_path is not None
with FileLock(bin_lock_path):
with open(bin_cache_path, 'rb') as f:
binary = pickle.load(f)["binary"]
if binary is None:
binary = self._compile(
*wargs, device=device_idx, attributes=attributes,
num_warps=num_warps, num_stages=num_stages,
constants=constants,
)
if bin_cache_path:
assert bin_lock_path is not None
with FileLock(bin_lock_path):
with open(bin_cache_path + ".tmp", "wb") as f:
pickle.dump({"binary": binary, "key": key}, f)
os.rename(bin_cache_path + ".tmp", bin_cache_path)
if JITFunction.cache_hook is not None:
JITFunction.cache_hook(key=key, binary=binary)
self.fn.bin_cache[key] = LoadedBinary(device_idx, binary)
def __call__(self, *wargs, grid, num_warps=4, num_stages=2, **kwargs):
# handle arguments passed by name
kwargs = {self.fn.arg_names.index(name): value for name, value in kwargs.items()}
@@ -608,112 +646,21 @@ class Kernel:
if len(wargs) != len(self.fn.arg_names):
raise TypeError(f"Function takes {len(self.fn.arg_names)} positional arguments but {len(wargs)} were given")
# handle annotations
for name, type in self.fn.__annotations__.items():
pos = self.fn.arg_names.index(name)
assert type == triton.language.core.constexpr
wargs[pos] = type(wargs[pos])
# device inference
tensor_idxs = [i for i, arg in enumerate(wargs) if hasattr(arg, 'data_ptr')]
if len(tensor_idxs) == 0:
raise ValueError("No Tensor argument found.")
invalid_args = []
device_ids = []
for idx in tensor_idxs:
curr = wargs[idx]
if not curr.is_cuda:
invalid_args.append(idx)
else:
device_ids.append(curr.device.index)
if invalid_args:
raise ValueError("Arguments at index {invalid_args} are on the wrong device.".format(invalid_args=invalid_args) +
" Only CUDA is supported at the moment")
device = torch.device('cuda', torch.cuda.current_device())
device_idx = device.index
# if len(set(device_ids)) != 1 or device_ids[0] != device_idx:
# # try to enable P2P communication
# for arg_idx, dst_idx in zip(tensor_idxs, device_ids):
# if dst_idx != device_idx:
# try:
# _triton.runtime.enable_peer_access(self.backend, wargs[arg_idx].data_ptr())
# except RuntimeError as e:
# raise RuntimeError("Cannot enable P2P access from device {} to device {}: {}"
# .format(device_idx, dst_idx, str(e)))
# enqueue kernel on the current device
torch.cuda.set_device(device_idx)
# attributes
args = [arg.data_ptr() if i in tensor_idxs else arg for i, arg in enumerate(wargs)]
attributes = {i: Kernel.pow2_divisor(a) for i, a in enumerate(args) \
if isinstance(a, int) and i not in self.fn.do_not_specialize}
# transforms ints whose value is one into constants for just-in-time compilation
constants = {i: arg for i, arg in enumerate(wargs) if isinstance(arg, int) and arg == 1}
constants.update({i: arg.value for i, arg in enumerate(wargs) if isinstance(arg, triton.language.constexpr)})
# compute hash for caching this kernel
types_key = Kernel._types_key(*wargs, tensor_idxs=tensor_idxs)
attr_key = tuple(attributes.items())
const_key = tuple(constants.items())
compute_capability = torch.cuda.get_device_capability(device)
key = (
self.fn.cache_key, version_key(), compute_capability,
types_key, attr_key, num_warps, num_stages, const_key
)
key = repr(key)
# get cached binary
drv_cache = self.fn.drv_cache
if key not in drv_cache:
hashed_key = hashlib.md5(key.encode("utf-8")).hexdigest()
# create cache directory
cache_dir = os.environ.get('TRITON_CACHE_DIR', '/tmp/triton/')
if cache_dir and not os.path.exists(cache_dir):
os.makedirs(cache_dir, exist_ok=True)
if cache_dir:
bin_cache_path = os.path.join(cache_dir, hashed_key)
bin_lock_path = bin_cache_path + ".lock"
else:
bin_cache_path = None
bin_lock_path = None
binary = None
if bin_cache_path and os.path.exists(bin_cache_path):
assert bin_lock_path is not None
with FileLock(bin_lock_path):
with open(bin_cache_path, 'rb') as f:
binary = pickle.load(f)["binary"]
if binary is None:
binary = self._compile(
*wargs, device=device_idx, attributes=attributes,
num_warps=num_warps, num_stages=num_stages,
constants=constants,
)
if bin_cache_path:
assert bin_lock_path is not None
with FileLock(bin_lock_path):
with open(bin_cache_path + ".tmp", "wb") as f:
pickle.dump({"binary": binary, "key": key}, f)
os.rename(bin_cache_path + ".tmp", bin_cache_path)
if JITFunction.cache_hook is not None:
JITFunction.cache_hook(key=key, binary=binary)
drv_cache[key] = LoadedBinary(device_idx, binary)
# pack arguments
fmt = ''.join(['P' if i in tensor_idxs else Kernel._type_name(arg) for i, arg in enumerate(wargs) if not isinstance(arg, triton.language.core.constexpr)])
params = struct.pack(fmt, *[arg for arg in args if not isinstance(arg, triton.language.core.constexpr)])
# enqueue cached function into stream
callable = drv_cache[key]
stream = torch.cuda.current_stream(device_idx).cuda_stream
csts = {self.fn.arg_names[i]: arg.value for i, arg in enumerate(wargs) if isinstance(arg, triton.language.core.constexpr)}
grid = grid(csts) if hasattr(grid, '__call__') else grid
if isinstance(grid, int):
grid = tuple(grid)
callable(stream, params, *grid)
return callable
for pos, _type in self.fn.annotations.items():
wargs[pos] = _type(wargs[pos])
# query device index and cuda stream
device = torch.cuda.current_device()
# query stream
# this is hacky but much faster than `torch.cuda.current_stream(device).cuda_stream`
# https://github.com/pytorch/pytorch/blob/master/c10/core/Stream.h#L154
# building a C wrapper to re-use the unpack function would add a build-time torch dependency
# and require different wheels for different torch versions -- undesirable!
bits = torch._C._cuda_getCurrentStream(device)
mask = 1 << 47
stream = ((bits & 0xFFFFFFFFFFFF) ^ mask) - mask
# make key for cache
return _triton.runtime.launch(wargs, self.fn.cache_key, self.fn.arg_names, device, stream,
self.fn.bin_cache, num_warps, num_stages, self.add_to_cache, grid)
class Launcher:
@@ -725,6 +672,7 @@ class Launcher:
return self.kernel(*wargs, **kwargs, grid=self.grid)
class Autotuner:
def __init__(self, kernel, arg_names, configs, key, reset_to_zero):
if not configs:
@@ -773,6 +721,11 @@ class Autotuner:
return self.kernel(*args, num_warps=config.num_warps, num_stages=config.num_stages, **kwargs, **config.kwargs)
@functools.lru_cache()
def compute_capability():
device = torch.device('cuda', 0)
return '-'.join(map(str, torch.cuda.get_device_capability(device)))
@functools.lru_cache()
def version_key():
import pkgutil
@@ -784,22 +737,27 @@ def version_key():
with open(triton._C.libtriton.__file__, "rb") as f:
contents += [hashlib.md5(f.read()).hexdigest()]
# language
for lib in pkgutil.iter_modules(triton.language.__path__):
language_path = os.path.join(*triton.__path__, 'language')
for lib in pkgutil.iter_modules([language_path]):
with open(lib.module_finder.find_spec(lib.name).origin, "rb") as f:
contents += [hashlib.md5(f.read()).hexdigest()]
# ptxas version
try:
ptxas_version = hashlib.md5(subprocess.check_output(["ptxas", "--version"])).hexdigest()
except Exception:
ptxas_version = None
return (triton.__version__, ptxas_version) + tuple(contents)
ptxas_version = ''
return '-'.join(triton.__version__) + '-' + ptxas_version + '-' + '-'.join(contents)
class JITFunction:
cache_hook = None
def _set_cache_key(self):
self.cache_key = (hashlib.md5(self.src.encode("utf-8")).hexdigest(), self.version)
self.cache_key = hashlib.md5(self.src.encode("utf-8")).hexdigest()
self.cache_key += str(self.version)
self.cache_key += version_key()
self.cache_key += compute_capability()
self.cache_key = hashlib.md5(self.cache_key.encode("utf-8")).hexdigest()
def __init__(self, fn, version=None, do_not_specialize=None):
# information of wrapped function
@@ -811,7 +769,7 @@ class JITFunction:
self.do_not_specialize = [] if do_not_specialize is None else\
[self.arg_names.index(arg) for arg in do_not_specialize]
# cache for callable driver objects (e.g. CUkernel)
self.drv_cache = dict()
self.bin_cache = dict()
# cache for binaries (on-disk)
self._set_cache_key()
# JITFunction can be instantiated as kernel
@@ -819,6 +777,7 @@ class JITFunction:
self.kernel_decorators = []
self.kernel = None
# annotations
self.annotations = {self.arg_names.index(name): ty for name, ty in fn.__annotations__.items()}
self.__annotations__ = fn.__annotations__
# forward docs
self.__doc__ = fn.__doc__
@@ -834,7 +793,7 @@ class JITFunction:
assert isinstance(tree.body[0], ast.FunctionDef)
return tree
def __call__(self, *args, generator: CodeGenerator, **meta):
def __call__(self, *args, generator: CodeGenerator):
try:
gscope = generator.gscope.copy()
lscope = generator.lscope.copy()

View File

@@ -119,6 +119,9 @@ class block:
self.shape = (1, )
if self.handle.type.is_block():
self.shape = self.handle.type.shape
self.numel = 1
for s in self.shape:
self.numel *= s
# Data-type wrapper
self.dtype = block._init_dtype(self.handle.type.scalar)
@@ -352,6 +355,13 @@ def program_id(axis, _builder=None):
:param axis: The axis of the 3D launch grid. Has to be either 0, 1 or 2.
:type axis: int
"""
# if axis == -1:
# pid0 = frontend.program_id(0, _builder)
# pid1 = frontend.program_id(1, _builder)
# pid2 = frontend.program_id(2, _builder)
# npg0 = frontend.num_programs(0, _builder)
# npg1 = frontend.num_programs(0, _builder)
# return pid0 + pid1*npg0 + pid2*npg0*npg1
return frontend.program_id(axis, _builder)