config: Add soak test for memtest.py

This patch adds a random option to memtest.py which allows the user to
easily test valid random tree topologies. The patch also adds a
wrapper script to run soak tests using the newly introduced option.

We also adjust the progress interval and progress limit check to make
the output less noisy, and avoid false positives.

Bring on the pain.

2 files changed, 136 insertions, 50 deletions

diff --git a/configs/example/memtest.py b/configs/example/memtest.py
index 9a66320d8..0df9f766f 100644
--- a/configs/example/memtest.py
+++ b/configs/example/memtest.py
@@ -40,11 +40,20 @@
 #          Andreas Hansson
 
 import optparse
+import random
 import sys
 
 import m5
 from m5.objects import *
 
+# This example script stress tests the memory system by creating false
+# sharing in a tree topology. At the bottom of the tree is a shared
+# memory, and then at each level a number of testers are attached,
+# along with a number of caches that them selves fan out to subtrees
+# of testers and caches. Thus, it is possible to create a system with
+# arbitrarily deep cache hierarchies, sharing or no sharing of caches,
+# and testers not only at the L1s, but also at the L2s, L3s etc.
+
 parser = optparse.OptionParser()
 
 parser.add_option("-a", "--atomic", action="store_true",
@@ -57,14 +66,6 @@ parser.add_option("-m", "--maxtick", type="int", default=m5.MaxTick,
                   metavar="T",
                   help="Stop after T ticks")
 
-# This example script stress tests the memory system by creating false
-# sharing in a tree topology. At the bottom of the tree is a shared
-# memory, and then at each level a number of testers are attached,
-# along with a number of caches that them selves fan out to subtrees
-# of testers and caches. Thus, it is possible to create a system with
-# arbitrarily deep cache hierarchies, sharing or no sharing of caches,
-# and testers not only at the L1s, but also at the L2s, L3s etc.
-#
 # The tree specification consists of two colon-separated lists of one
 # or more integers, one for the caches, and one for the testers. The
 # first integer is the number of caches/testers closest to main
@@ -92,8 +93,9 @@ 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=10000,
+parser.add_option("-r", "--random", action="store_true",
+                  help="Generate a random tree topology")
+parser.add_option("--progress", type="int", default=100000,
                   metavar="NLOADS",
                   help="Progress message interval "
                   "[default: %default]")
@@ -108,55 +110,69 @@ if args:
      print "Error: script doesn't take any positional arguments"
      sys.exit(1)
 
+# Get the total number of testers
+def numtesters(cachespec, testerspec):
+     # Determine the tester multiplier for each level as the
+     # elements are per subsystem and it fans out
+     multiplier = [1]
+     for c in cachespec:
+          multiplier.append(multiplier[-1] * c)
+
+     total = 0
+     for t, m in zip(testerspec, multiplier):
+          total += t * m
+
+     return total
+
 block_size = 64
 
 # Start by parsing the command line options and do some basic sanity
 # checking
-try:
-     cachespec = [int(x) for x in options.caches.split(':')]
-     testerspec = [int(x) for x in options.testers.split(':')]
-except:
-     print "Error: Unable to parse caches or testers option"
-     sys.exit(1)
-
-if len(cachespec) < 1:
-     print "Error: Must have at least one level of caches"
-     sys.exit(1)
-
-if len(cachespec) != len(testerspec) - 1:
-     print "Error: Testers must have one element more than caches"
-     sys.exit(1)
+if options.random:
+     # Generate a tree with a valid number of testers
+     while True:
+          tree_depth = random.randint(1, 4)
+          cachespec = [random.randint(1, 3) for i in range(tree_depth)]
+          testerspec = [random.randint(1, 3) for i in range(tree_depth + 1)]
+          if numtesters(cachespec, testerspec) < block_size:
+               break
+
+     print "Generated random tree -c", ':'.join(map(str, cachespec)), \
+         "-t", ':'.join(map(str, testerspec))
+else:
+     try:
+          cachespec = [int(x) for x in options.caches.split(':')]
+          testerspec = [int(x) for x in options.testers.split(':')]
+     except:
+          print "Error: Unable to parse caches or testers option"
+          sys.exit(1)
 
-if testerspec[-1] == 0:
-     print "Error: Must have testers at the uppermost level"
-     sys.exit(1)
+     if len(cachespec) < 1:
+          print "Error: Must have at least one level of caches"
+          sys.exit(1)
 
-for t in testerspec:
-     if t < 0:
-          print "Error: Cannot have a negative number of testers"
+     if len(cachespec) != len(testerspec) - 1:
+          print "Error: Testers must have one element more than caches"
           sys.exit(1)
 
-for c in cachespec:
-     if c < 1:
-          print "Error: Must have 1 or more caches at each level"
+     if testerspec[-1] == 0:
+          print "Error: Must have testers at the uppermost level"
           sys.exit(1)
 
-# Determine the tester multiplier for each level as the string
-# elements are per subsystem and it fans out
-multiplier = [1]
-for c in cachespec:
-     if c < 1:
-          print "Error: Must have at least one cache per level"
-     multiplier.append(multiplier[-1] * c)
-
-numtesters = 0
-for t, m in zip(testerspec, multiplier):
-     numtesters += t * m
-
-if numtesters > block_size:
-     print "Error: Number of testers limited to %s because of false sharing" \
-           % (block_size)
-     sys.exit(1)
+     for t in testerspec:
+          if t < 0:
+               print "Error: Cannot have a negative number of testers"
+               sys.exit(1)
+
+     for c in cachespec:
+          if c < 1:
+               print "Error: Must have 1 or more caches at each level"
+               sys.exit(1)
+
+     if numtesters(cachespec, testerspec) > block_size:
+          print "Error: Limited to %s testers because of false sharing" \
+              % (block_size)
+          sys.exit(1)
 
 # Define a prototype L1 cache that we scale for all successive levels
 proto_l1 = BaseCache(size = '32kB', assoc = 4,
@@ -223,7 +239,7 @@ def make_cache_level(ncaches, prototypes, level, next_cache):
      # and also make the interval of packet injection longer for the
      # testers closer to the memory (larger level) to prevent them
      # hogging all the bandwidth
-     limit = (len(cachespec) - level + 1) * 10000000
+     limit = (len(cachespec) - level + 1) * 100000000
      testers = [proto_tester(interval = 10 * (level * level + 1),
                              progress_check = limit) \
                      for i in xrange(ntesters)]
diff --git a/util/memtest-soak.py b/util/memtest-soak.py
new file mode 100755
index 000000000..2ece09c21
--- /dev/null
+++ b/util/memtest-soak.py
@@ -0,0 +1,70 @@
+#! /usr/bin/env python
+
+# Copyright (c) 2015 ARM Limited
+# All rights reserved
+#
+# The license below extends only to copyright in the software and shall
+# not be construed as granting a license to any other intellectual
+# property including but not limited to intellectual property relating
+# to a hardware implementation of the functionality of the software
+# licensed hereunder.  You may use the software subject to the license
+# terms below provided that you ensure that this notice is replicated
+# unmodified and in its entirety in all distributions of the software,
+# modified or unmodified, in source code or in binary form.
+#
+# 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: Andreas Hansson
+
+import optparse
+import subprocess
+import sys
+
+parser = optparse.OptionParser()
+
+# This script lets the user run a soak test using the false-sharing
+# memtest.py example script. It runs a number of iterations with
+# random tree topologies generated for each run, and runs for a number
+# of ticks. Both the iteration count and the ticks for each run can be
+# set on the command line.
+
+parser.add_option('-c', '--count', type='int', default=100)
+parser.add_option('-t', '--ticks', type='int', default=100000000000)
+
+(options, args) = parser.parse_args()
+
+if len(args) != 1:
+    print "Error: Expecting a single argument specifying the gem5 binary"
+    sys.exit(1)
+
+gem5_binary = args[0]
+
+for i in range(options.count):
+    status = subprocess.call([gem5_binary, 'configs/example/memtest.py',
+                              '-r', '-m %d' % (options.ticks)])
+    if status != 0:
+        print "Error: memtest run failed\n"
+        sys.exit(1)
+
+print "memtest soak finished without errors"