configs: Add a lat_mem_rd style test script

This patch adds a config script that broadly replicates the behaviour
of lat_mem_rd. The test is based on traffic generators, and as such we
simply randomise addresses in increasingly large ranges, and play them
back using the trace functionality of the traffic generator.

The test script is accompanied by a post-processing and visualisation
script. At the moment no configurability is added to tweak the memory
hierarchy, but a follow on patch could easily extend the
functionality.

1 files changed, 151 insertions, 0 deletions

diff --git a/util/dram_lat_mem_rd_plot.py b/util/dram_lat_mem_rd_plot.py
new file mode 100755
index 000000000..72e1528c3
--- /dev/null
+++ b/util/dram_lat_mem_rd_plot.py
@@ -0,0 +1,151 @@
+#!/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
+
+try:
+    import matplotlib.pyplot as plt
+    import matplotlib as mpl
+    import numpy as np
+except ImportError:
+    print "Failed to import matplotlib and numpy"
+    exit(-1)
+
+import sys
+import re
+
+# This script is intended to post process and plot the output from
+# running configs/dram/lat_mem_rd.py, as such it parses the simout and
+# stats.txt to get the relevant data points.
+def main():
+
+    if len(sys.argv) != 2:
+        print "Usage: ", sys.argv[0], "<simout directory>"
+        exit(-1)
+
+    try:
+        stats = open(sys.argv[1] + '/stats.txt', 'r')
+    except IOError:
+        print "Failed to open ", sys.argv[1] + '/stats.txt', " for reading"
+        exit(-1)
+
+    try:
+        simout = open(sys.argv[1] + '/simout', 'r')
+    except IOError:
+        print "Failed to open ", sys.argv[1] + '/simout', " for reading"
+        exit(-1)
+
+    # Get the address ranges
+    got_ranges = False
+    ranges = []
+
+    iterations = 1
+
+    for line in simout:
+        if got_ranges:
+            ranges.append(int(line) / 1024)
+
+        match = re.match("lat_mem_rd with (\d+) iterations, ranges:.*", line)
+        if match:
+            got_ranges = True
+            iterations = int(match.groups(0)[0])
+
+    simout.close()
+
+    if not got_ranges:
+        print "Failed to get address ranges, ensure simout is up-to-date"
+        exit(-1)
+
+    # Now parse the stats
+    raw_rd_lat = []
+
+    for line in stats:
+        match = re.match(".*readLatencyHist::mean\s+(.+)\s+#.*", line)
+        if match:
+            raw_rd_lat.append(float(match.groups(0)[0]) / 1000)
+    stats.close()
+
+    # The stats also contain the warming, so filter the latency stats
+    i = 0
+    filtered_rd_lat = []
+    for l in raw_rd_lat:
+        if i % (iterations + 1) == 0:
+            pass
+        else:
+            filtered_rd_lat.append(l)
+        i = i + 1
+
+    # Next we need to take care of the iterations
+    rd_lat = []
+    for i in range(iterations):
+        rd_lat.append(filtered_rd_lat[i::iterations])
+
+    final_rd_lat = map(lambda p: min(p), zip(*rd_lat))
+
+    # Sanity check
+    if not (len(ranges) == len(final_rd_lat)):
+        print "Address ranges (%d) and read latency (%d) do not match" % \
+            (len(ranges), len(final_rd_lat))
+        exit(-1)
+
+    for (r, l) in zip(ranges, final_rd_lat):
+        print r, round(l, 2)
+
+    # lazy version to check if an integer is a power of two
+    def is_pow2(num):
+        return num != 0 and ((num & (num - 1)) == 0)
+
+    plt.semilogx(ranges, final_rd_lat)
+
+    # create human readable labels
+    xticks_locations = [r for r in ranges if is_pow2(r)]
+    xticks_labels = []
+    for x in xticks_locations:
+        if x < 1024:
+            xticks_labels.append('%d kB' % x)
+        else:
+            xticks_labels.append('%d MB' % (x / 1024))
+    plt.xticks(xticks_locations, xticks_labels, rotation=-45)
+
+    plt.minorticks_off()
+    plt.xlim((xticks_locations[0], xticks_locations[-1]))
+    plt.ylabel("Latency (ns)")
+    plt.grid(True)
+    plt.show()
+
+if __name__ == "__main__":
+    main()