2018-08-13 14:01:38 +02:00

353 lines
13 KiB
Python

# -*- coding: utf-8 -*-
"""
This python module implements the different helper functions and
classes
Copyright (C) 2018 SINTEF ICT
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
"""
import os
import numpy as np
import time
import re
import io
import hashlib
import logging
import pycuda.compiler as cuda_compiler
import pycuda.gpuarray
import pycuda.driver as cuda
"""
Class which keeps track of time spent for a section of code
"""
class Timer(object):
def __init__(self, tag):
self.tag = tag
self.logger = logging.getLogger(__name__)
def __enter__(self):
self.start = time.time()
return self
def __exit__(self, *args):
self.end = time.time()
self.secs = self.end - self.start
self.msecs = self.secs * 1000 # millisecs
self.logger.info("%s: %f ms", self.tag, self.msecs)
"""
Class which keeps track of the CUDA context and some helper functions
"""
class CudaContext(object):
def __init__(self, verbose=True, blocking=False, use_cache=True):
self.verbose = verbose
self.blocking = blocking
self.use_cache = use_cache
self.logger = logging.getLogger(__name__)
self.kernels = {}
self.module_path = os.path.dirname(os.path.realpath(__file__))
#Initialize cuda (must be first call to PyCUDA)
cuda.init(flags=0)
#Print some info about CUDA
self.logger.info("CUDA version %s", str(cuda.get_version()))
self.logger.info("Driver version %s", str(cuda.get_driver_version()))
self.cuda_device = cuda.Device(0)
if (self.verbose):
self.logger.info("Using '%s' GPU", self.cuda_device.name())
self.logger.debug(" => compute capability: %s", str(self.cuda_device.compute_capability()))
self.logger.debug(" => memory: %d MB", self.cuda_device.total_memory() / (1024*1024))
# Create the CUDA context
if (self.blocking):
self.cuda_context = self.cuda_device.make_context(flags=cuda.ctx_flags.SCHED_BLOCKING_SYNC)
self.logger.warning("Using blocking context")
else:
self.cuda_context = self.cuda_device.make_context(flags=cuda.ctx_flags.SCHED_AUTO)
self.logger.info("Created context handle <%s>", str(self.cuda_context.handle))
#Create cache dir for cubin files
if (self.use_cache):
self.cache_path = os.path.join(self.module_path, "cuda_cache")
if not os.path.isdir(self.cache_path):
os.mkdir(self.cache_path)
self.logger.debug("Using CUDA cache dir %s", self.cache_path)
def __del__(self, *args):
self.logger.info("Cleaning up CUDA context handle <%s>", str(self.cuda_context.handle))
# Loop over all contexts in stack, and remove "this"
other_contexts = []
while (cuda.Context.get_current() != None):
context = cuda.Context.get_current()
if (context.handle != self.cuda_context.handle):
self.logger.debug("<%s> Popping <%s> (*not* ours)", str(self.cuda_context.handle), str(context.handle))
other_contexts = [context] + other_contexts
cuda.Context.pop()
else:
self.logger.debug("<%s> Popping <%s> (ours)", str(self.cuda_context.handle), str(context.handle))
cuda.Context.pop()
# Add all the contexts we popped that were not our own
for context in other_contexts:
self.logger.debug("<%s> Pushing <%s>", str(self.cuda_context.handle), str(context.handle))
cuda.Context.push(context)
self.logger.debug("<%s> Detaching", str(self.cuda_context.handle))
self.cuda_context.detach()
def __str__(self):
return "CudaContext id " + str(self.cuda_context.handle)
def hash_kernel(kernel_filename, include_dirs, verbose=False):
# Generate a kernel ID for our caches
num_includes = 0
max_includes = 100
kernel_hasher = hashlib.md5()
logger = logging.getLogger(__name__)
# Loop over file and includes, and check if something has changed
files = [kernel_filename]
while len(files):
if (num_includes > max_includes):
raise("Maximum number of includes reached - circular include in {:}?".format(kernel_filename))
filename = files.pop()
logger.debug("Hashing %s", filename)
modified = os.path.getmtime(filename)
# Open the file
with io.open(filename, "r") as file:
# Search for #inclue <something> and also hash the file
file_str = file.read()
kernel_hasher.update(file_str.encode('utf-8'))
kernel_hasher.update(str(modified).encode('utf-8'))
#Find all includes
includes = re.findall('^\W*#include\W+(.+?)\W*$', file_str, re.M)
# Loop over everything that looks like an include
for include_file in includes:
#Search through include directories for the file
file_path = os.path.dirname(filename)
for include_path in [file_path] + include_dirs:
# If we find it, add it to list of files to check
temp_path = os.path.join(include_path, include_file)
if (os.path.isfile(temp_path)):
files = files + [temp_path]
num_includes = num_includes + 1 #For circular includes...
break
return kernel_hasher.hexdigest()
"""
Reads a text file and creates an OpenCL kernel from that
"""
def get_prepared_kernel(self, kernel_filename, kernel_function_name, \
prepared_call_args, \
include_dirs=[], verbose=False, no_extern_c=False,
**kwargs):
"""
Helper function to print compilation output
"""
def cuda_compile_message_handler(compile_success_bool, info_str, error_str):
self.logger.debug("Compilation returned %s", str(compile_success_bool))
if info_str:
self.logger.debug("Info: %s", info_str)
if error_str:
self.logger.debug("Error: %s", error_str)
self.logger.debug("Getting %s", kernel_filename)
# Create a hash of the kernel (and its includes)
kwargs_hasher = hashlib.md5()
kwargs_hasher.update(str(kwargs).encode('utf-8'));
kwargs_hash = kwargs_hasher.hexdigest()
kwargs_hasher = None
root, ext = os.path.splitext(kernel_filename)
kernel_hash = root \
+ "_" + CudaContext.hash_kernel( \
os.path.join(self.module_path, kernel_filename), \
include_dirs=[self.module_path] + include_dirs, \
verbose=verbose) \
+ "_" + kwargs_hash \
+ ext
cached_kernel_filename = os.path.join(self.cache_path, kernel_hash)
# If we have the kernel in our hashmap, return it
if (kernel_hash in self.kernels.keys()):
self.logger.debug("Found kernel %s cached in hashmap (%s)", kernel_filename, kernel_hash)
return self.kernels[kernel_hash]
# If we have it on disk, return it
elif (self.use_cache and os.path.isfile(cached_kernel_filename)):
self.logger.debug("Found kernel %s cached on disk (%s)", kernel_filename, kernel_hash)
with io.open(cached_kernel_filename, "rb") as file:
file_str = file.read()
module = cuda.module_from_buffer(file_str, message_handler=cuda_compile_message_handler)
kernel = module.get_function(kernel_function_name)
kernel.prepare(prepared_call_args)
self.kernels[kernel_hash] = kernel
return kernel
# Otherwise, compile it from source
else:
self.logger.debug("Compiling %s (%s)", kernel_filename, kernel_hash)
#Create kernel string
kernel_string = ""
for key, value in kwargs.items():
kernel_string += "#define {:s} {:s}\n".format(str(key), str(value))
kernel_string += '#include "{:s}"'.format(os.path.join(self.module_path, kernel_filename))
if (self.use_cache):
with io.open(cached_kernel_filename + ".txt", "w") as file:
file.write(kernel_string)
with Timer("compiler") as timer:
cubin = cuda_compiler.compile(kernel_string, include_dirs=include_dirs, no_extern_c=no_extern_c, cache_dir=False)
module = cuda.module_from_buffer(cubin, message_handler=cuda_compile_message_handler)
if (self.use_cache):
with io.open(cached_kernel_filename, "wb") as file:
file.write(cubin)
kernel = module.get_function(kernel_function_name)
kernel.prepare(prepared_call_args)
self.kernels[kernel_hash] = kernel
return kernel
"""
Clears the kernel cache (useful for debugging & development)
"""
def clear_kernel_cache(self):
self.kernels = {}
"""
Class that holds data
"""
class CUDAArray2D:
"""
Uploads initial data to the CL device
"""
def __init__(self, stream, nx, ny, halo_x, halo_y, data):
self.nx = nx
self.ny = ny
self.nx_halo = nx + 2*halo_x
self.ny_halo = ny + 2*halo_y
#Make sure data is in proper format
assert np.issubdtype(data.dtype, np.float32), "Wrong datatype: %s" % str(data.dtype)
assert not np.isfortran(data), "Wrong datatype (Fortran, expected C)"
assert data.shape == (self.ny_halo, self.nx_halo), "Wrong data shape: %s vs %s" % (str(data.shape), str((self.ny_halo, self.nx_halo)))
#Upload data to the device
self.data = pycuda.gpuarray.to_gpu_async(data, stream=stream)
self.bytes_per_float = data.itemsize
assert(self.bytes_per_float == 4)
self.pitch = np.int32((self.nx_halo)*self.bytes_per_float)
"""
Enables downloading data from CL device to Python
"""
def download(self, stream, async=False):
#Copy data from device to host
if (async):
host_data = self.data.get_async(stream=stream)
return host_data
else:
host_data = self.data.get(stream=stream)#, pagelocked=True) # pagelocked causes crash on windows at least
return host_data
"""
A class representing an Arakawa A type (unstaggered, logically Cartesian) grid
"""
class SWEDataArakawaA:
"""
Uploads initial data to the CL device
"""
def __init__(self, stream, nx, ny, halo_x, halo_y, h0, hu0, hv0):
self.h0 = CUDAArray2D(stream, nx, ny, halo_x, halo_y, h0)
self.hu0 = CUDAArray2D(stream, nx, ny, halo_x, halo_y, hu0)
self.hv0 = CUDAArray2D(stream, nx, ny, halo_x, halo_y, hv0)
self.h1 = CUDAArray2D(stream, nx, ny, halo_x, halo_y, h0)
self.hu1 = CUDAArray2D(stream, nx, ny, halo_x, halo_y, hu0)
self.hv1 = CUDAArray2D(stream, nx, ny, halo_x, halo_y, hv0)
"""
Swaps the variables after a timestep has been completed
"""
def swap(self):
self.h1, self.h0 = self.h0, self.h1
self.hu1, self.hu0 = self.hu0, self.hu1
self.hv1, self.hv0 = self.hv0, self.hv1
"""
Enables downloading data from CL device to Python
"""
def download(self, stream):
h_cpu = self.h0.download(stream, async=True)
hu_cpu = self.hu0.download(stream, async=True)
hv_cpu = self.hv0.download(stream, async=False)
return h_cpu, hu_cpu, hv_cpu