diff options
Diffstat (limited to 'tests')
| -rw-r--r-- | tests/avocado/acpi-bits/bits-tests/smilatency.py2 | 106 |
1 files changed, 106 insertions, 0 deletions
diff --git a/tests/avocado/acpi-bits/bits-tests/smilatency.py2 b/tests/avocado/acpi-bits/bits-tests/smilatency.py2 new file mode 100644 index 0000000..48083bf --- /dev/null +++ b/tests/avocado/acpi-bits/bits-tests/smilatency.py2 @@ -0,0 +1,106 @@ +# Copyright (c) 2015, Intel Corporation +# All rights reserved. +# +# SPDX-License-Identifier: BSD-3-Clause + +# 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 Intel Corporation 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. + +# This script runs only from the biosbits VM. + +"""SMI latency test.""" + +import bits +from collections import namedtuple +import testsuite +import time +import usb + +def register_tests(): + testsuite.add_test("SMI latency test", smi_latency); + testsuite.add_test("SMI latency test with USB disabled via BIOS handoff", test_with_usb_disabled, runall=False); + +def smi_latency(): + MSR_SMI_COUNT = 0x34 + + print "Warning: touching the keyboard can affect the results of this test." + + tsc_per_sec = bits.tsc_per_sec() + tsc_per_usec = tsc_per_sec / (1000 * 1000) + bins = [long(tsc_per_usec * 10**i) for i in range(9)] + bin_descs = [ + "0 < t <= 1us", + "1us < t <= 10us", + "10us < t <= 100us", + "100us < t <= 1ms", + "1ms < t <= 10ms", + "10ms < t <= 100ms", + "100ms < t <= 1s ", + "1s < t <= 10s ", + "10s < t <= 100s ", + "100s < t ", + ] + + print "Starting test. Wait here, I will be back in 15 seconds." + (max_latency, smi_count_delta, bins) = bits.smi_latency(long(15 * tsc_per_sec), bins) + BinType = namedtuple('BinType', ("max", "total", "count", "times")) + bins = [BinType(*b) for b in bins] + + testsuite.test("SMI latency < 150us to minimize risk of OS timeouts", max_latency / tsc_per_usec <= 150) + if not testsuite.show_detail(): + return + + for bin, desc in zip(bins, bin_descs): + if bin.count == 0: + continue + testsuite.print_detail("{}; average = {}; count = {}".format(desc, bits.format_tsc(bin.total/bin.count), bin.count)) + deltas = (bits.format_tsc(t2 - t1) for t1,t2 in zip(bin.times, bin.times[1:])) + testsuite.print_detail(" Times between first few observations: {}".format(" ".join("{:>6}".format(delta) for delta in deltas))) + + if smi_count_delta is not None: + testsuite.print_detail("{} SMI detected using MSR_SMI_COUNT (MSR {:#x})".format(smi_count_delta, MSR_SMI_COUNT)) + + testsuite.print_detail("Summary of impact: observed maximum latency = {}".format(bits.format_tsc(max_latency))) + +def test_with_usb_disabled(): + if usb.handoff_to_os(): + smi_latency() + +def average_io_smi(port, value, count): + def f(): + tsc_start = bits.rdtsc() + bits.outb(port, value) + return bits.rdtsc() - tsc_start + counts = [f() for i in range(count)] + return sum(counts)/len(counts) + +def time_io_smi(port=0xb2, value=0, count=1000): + count_for_estimate = 10 + start = time.time() + average_io_smi(port, value, count_for_estimate) + avg10 = time.time() - start + estimate = avg10 * count/count_for_estimate + if estimate > 1: + print "Running test, estimated time: {}s".format(int(estimate)) + average = average_io_smi(port, value, count) + print "Average of {} SMIs (via outb, port={:#x}, value={:#x}): {}".format(count, port, value, bits.format_tsc(average)) |