#!/bin/bash # udelay() test script # # Test is executed by writing and reading to /sys/kernel/debug/udelay_test # and exercises a variety of delays to ensure that udelay() is delaying # at least as long as requested (as compared to ktime). # # Copyright (C) 2014 Google, Inc. # # This software is licensed under the terms of the GNU General Public # License version 2, as published by the Free Software Foundation, and # may be copied, distributed, and modified under those terms. # # 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. MODULE_NAME=udelay_test UDELAY_PATH=/sys/kernel/debug/udelay_test setup() { /sbin/modprobe -q $MODULE_NAME tmp_file=`mktemp` } test_one() { delay=$1 echo $delay > $UDELAY_PATH tee -a $tmp_file < $UDELAY_PATH } cleanup() { if [ -f $tmp_file ]; then rm $tmp_file fi /sbin/modprobe -q -r $MODULE_NAME } trap cleanup EXIT setup # Delay for a variety of times. # 1..200, 200..500 (by 10), 500..2000 (by 100) for (( delay = 1; delay < 200; delay += 1 )); do test_one $delay done for (( delay = 200; delay < 500; delay += 10 )); do test_one $delay done for (( delay = 500; delay <= 2000; delay += 100 )); do test_one $delay done # Search for failures count=`grep -c FAIL $tmp_file` if [ $? -eq "0" ]; then echo "ERROR: $count delays failed to delay long enough" retcode=1 fi exit $retcode lauser
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authorBjorn Helgaas <bhelgaas@google.com>2017-01-27 15:00:45 -0600
committerBjorn Helgaas <bhelgaas@google.com>2017-01-27 15:00:45 -0600
commit030305d69fc6963c16003f50d7e8d74b02d0a143 (patch)
tree363a4e34d199178769b7e7eeb26ea2620a55847b /tools/testing/selftests/rcutorture/doc
parent4d191b1b63c209e37bf27938ef365244d3c41084 (diff)
PCI/ASPM: Handle PCI-to-PCIe bridges as roots of PCIe hierarchies
In a struct pcie_link_state, link->root points to the pcie_link_state of the root of the PCIe hierarchy. For the topmost link, this points to itself (link->root = link). For others, we copy the pointer from the parent (link->root = link->parent->root). Previously we recognized that Root Ports originated PCIe hierarchies, but we treated PCI/PCI-X to PCIe Bridges as being in the middle of the hierarchy, and when we tried to copy the pointer from link->parent->root, there was no parent, and we dereferenced a NULL pointer: BUG: unable to handle kernel NULL pointer dereference at 0000000000000090 IP: [<ffffffff9e424350>] pcie_aspm_init_link_state+0x170/0x820 Recognize that PCI/PCI-X to PCIe Bridges originate PCIe hierarchies just like Root Ports do, so link->root for these devices should also point to itself. Fixes: 51ebfc92b72b ("PCI: Enumerate switches below PCI-to-PCIe bridges") Link: https://bugzilla.kernel.org/show_bug.cgi?id=193411 Link: https://bugzilla.opensuse.org/show_bug.cgi?id=1022181 Tested-by: lists@ssl-mail.com Tested-by: Jayachandran C. <jnair@caviumnetworks.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> CC: stable@vger.kernel.org # v4.2+
Diffstat (limited to 'tools/testing/selftests/rcutorture/doc')