gem5/configs/example/memtest.py
Andreas Hansson b00949d88b MEM: Enable multiple distributed generalized memories
This patch removes the assumption on having on single instance of
PhysicalMemory, and enables a distributed memory where the individual
memories in the system are each responsible for a single contiguous
address range.

All memories inherit from an AbstractMemory that encompasses the basic
behaviuor of a random access memory, and provides untimed access
methods. What was previously called PhysicalMemory is now
SimpleMemory, and a subclass of AbstractMemory. All future types of
memory controllers should inherit from AbstractMemory.

To enable e.g. the atomic CPU and RubyPort to access the now
distributed memory, the system has a wrapper class, called
PhysicalMemory that is aware of all the memories in the system and
their associated address ranges. This class thus acts as an
infinitely-fast bus and performs address decoding for these "shortcut"
accesses. Each memory can specify that it should not be part of the
global address map (used e.g. by the functional memories by some
testers). Moreover, each memory can be configured to be reported to
the OS configuration table, useful for populating ATAG structures, and
any potential ACPI tables.

Checkpointing support currently assumes that all memories have the
same size and organisation when creating and resuming from the
checkpoint. A future patch will enable a more flexible
re-organisation.

--HG--
rename : src/mem/PhysicalMemory.py => src/mem/AbstractMemory.py
rename : src/mem/PhysicalMemory.py => src/mem/SimpleMemory.py
rename : src/mem/physical.cc => src/mem/abstract_mem.cc
rename : src/mem/physical.hh => src/mem/abstract_mem.hh
rename : src/mem/physical.cc => src/mem/simple_mem.cc
rename : src/mem/physical.hh => src/mem/simple_mem.hh
2012-04-06 13:46:31 -04:00

199 lines
7.3 KiB
Python

# Copyright (c) 2006-2007 The Regents of The University of Michigan
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are
# met: redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer;
# redistributions in binary form must reproduce the above copyright
# notice, this list of conditions and the following disclaimer in the
# documentation and/or other materials provided with the distribution;
# neither the name of the copyright holders nor the names of its
# contributors may be used to endorse or promote products derived from
# this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#
# Authors: Ron Dreslinski
import optparse
import sys
import m5
from m5.objects import *
parser = optparse.OptionParser()
parser.add_option("-a", "--atomic", action="store_true",
help="Use atomic (non-timing) mode")
parser.add_option("-b", "--blocking", action="store_true",
help="Use blocking caches")
parser.add_option("-l", "--maxloads", metavar="N", default=0,
help="Stop after N loads")
parser.add_option("-m", "--maxtick", type="int", default=m5.MaxTick,
metavar="T",
help="Stop after T ticks")
#
# The "tree" specification is a colon-separated list of one or more
# integers. The first integer is the number of caches/testers
# connected directly to main memory. The last integer in the list is
# the number of testers associated with the uppermost level of memory
# (L1 cache, if there are caches, or main memory if no caches). Thus
# if there is only one integer, there are no caches, and the integer
# specifies the number of testers connected directly to main memory.
# The other integers (if any) specify the number of caches at each
# level of the hierarchy between.
#
# Examples:
#
# "2:1" Two caches connected to memory with a single tester behind each
# (single-level hierarchy, two testers total)
#
# "2:2:1" Two-level hierarchy, 2 L1s behind each of 2 L2s, 4 testers total
#
parser.add_option("-t", "--treespec", type="string", default="8:1",
help="Colon-separated multilevel tree specification, "
"see script comments for details "
"[default: %default]")
parser.add_option("--force-bus", action="store_true",
help="Use bus between levels even with single cache")
parser.add_option("-f", "--functional", type="int", default=0,
metavar="PCT",
help="Target percentage of functional accesses "
"[default: %default]")
parser.add_option("-u", "--uncacheable", type="int", default=0,
metavar="PCT",
help="Target percentage of uncacheable accesses "
"[default: %default]")
parser.add_option("--progress", type="int", default=1000,
metavar="NLOADS",
help="Progress message interval "
"[default: %default]")
(options, args) = parser.parse_args()
if args:
print "Error: script doesn't take any positional arguments"
sys.exit(1)
block_size = 64
try:
treespec = [int(x) for x in options.treespec.split(':')]
numtesters = reduce(lambda x,y: x*y, treespec)
except:
print "Error parsing treespec option"
sys.exit(1)
if numtesters > block_size:
print "Error: Number of testers limited to %s because of false sharing" \
% (block_size)
sys.exit(1)
if len(treespec) < 1:
print "Error parsing treespec"
sys.exit(1)
# define prototype L1 cache
proto_l1 = BaseCache(size = '32kB', assoc = 4, block_size = block_size,
latency = '1ns', tgts_per_mshr = 8)
if options.blocking:
proto_l1.mshrs = 1
else:
proto_l1.mshrs = 4
# build a list of prototypes, one for each level of treespec, starting
# at the end (last entry is tester objects)
prototypes = [ MemTest(atomic=options.atomic, max_loads=options.maxloads,
percent_functional=options.functional,
percent_uncacheable=options.uncacheable,
progress_interval=options.progress) ]
# next comes L1 cache, if any
if len(treespec) > 1:
prototypes.insert(0, proto_l1)
# now add additional cache levels (if any) by scaling L1 params
for scale in treespec[:-2]:
# clone previous level and update params
prev = prototypes[0]
next = prev()
next.size = prev.size * scale
next.latency = prev.latency * 10
next.assoc = prev.assoc * scale
next.mshrs = prev.mshrs * scale
prototypes.insert(0, next)
# system simulated
system = System(funcmem = SimpleMemory(in_addr_map = False),
physmem = SimpleMemory(latency = "100ns"))
def make_level(spec, prototypes, attach_obj, attach_port):
fanout = spec[0]
parent = attach_obj # use attach obj as config parent too
if len(spec) > 1 and (fanout > 1 or options.force_bus):
port = getattr(attach_obj, attach_port)
new_bus = Bus(clock="500MHz", width=16)
if (port.role == 'MASTER'):
new_bus.slave = port
attach_port = "master"
else:
new_bus.master = port
attach_port = "slave"
parent.cpu_side_bus = new_bus
attach_obj = new_bus
objs = [prototypes[0]() for i in xrange(fanout)]
if len(spec) > 1:
# we just built caches, more levels to go
parent.cache = objs
for cache in objs:
cache.mem_side = getattr(attach_obj, attach_port)
make_level(spec[1:], prototypes[1:], cache, "cpu_side")
else:
# we just built the MemTest objects
parent.cpu = objs
for t in objs:
t.test = getattr(attach_obj, attach_port)
t.functional = system.funcmem.port
make_level(treespec, prototypes, system.physmem, "port")
# -----------------------
# run simulation
# -----------------------
root = Root( full_system = False, system = system )
if options.atomic:
root.system.mem_mode = 'atomic'
else:
root.system.mem_mode = 'timing'
# The system port is never used in the tester so merely connect it
# to avoid problems
root.system.system_port = root.system.physmem.port
# Not much point in this being higher than the L1 latency
m5.ticks.setGlobalFrequency('1ns')
# instantiate configuration
m5.instantiate()
# simulate until program terminates
exit_event = m5.simulate(options.maxtick)
print 'Exiting @ tick', m5.curTick(), 'because', exit_event.getCause()