91 lines
2.9 KiB
Bash
91 lines
2.9 KiB
Bash
#!/bin/bash
|
|
|
|
#
|
|
# Copyright (c) 2017 Wind River Systems, Inc.
|
|
#
|
|
# SPDX-License-Identifier: Apache-2.0
|
|
#
|
|
# Purpose: set PM QoS resume latency constraints for CPUs.
|
|
# Usage: /usr/bin/set-cpu-wakeup-latency.sh policy cpulist
|
|
# policy may be either "low" or "high" to set appropriate latency.
|
|
# "low" means HALT (C1) is the deepest C-state we allow the CPU to enter.
|
|
# "high" means we allow the CPU to sleep as deeply as possible.
|
|
# cpulist is for specifying a numerical list of processors.
|
|
# It may contain multiple items, separated by comma, and ranges.
|
|
# For example, 0,5,7,9-11.
|
|
|
|
# Define minimal path
|
|
PATH=/bin:/usr/bin:/usr/local/bin
|
|
|
|
LOG_FUNCTIONS=${LOG_FUNCTIONS:-"/etc/init.d/log_functions.sh"}
|
|
CPUMAP_FUNCTIONS=${CPUMAP_FUNCTIONS:-"/etc/init.d/cpumap_functions.sh"}
|
|
[[ -e ${LOG_FUNCTIONS} ]] && source ${LOG_FUNCTIONS}
|
|
[[ -e ${CPUMAP_FUNCTIONS} ]] && source ${CPUMAP_FUNCTIONS}
|
|
|
|
if [ $UID -ne 0 ]; then
|
|
log_error "$0 requires root or sudo privileges"
|
|
exit 1
|
|
fi
|
|
|
|
if [ "$#" -ne 2 ]; then
|
|
log_error "$0 requires policy and cpulist parameters"
|
|
exit 1
|
|
fi
|
|
|
|
POLICY=$1
|
|
CPU_LIST=$2
|
|
NUMBER_OF_CPUS=$(getconf _NPROCESSORS_CONF 2>/dev/null)
|
|
STATUS=1
|
|
|
|
for CPU_NUM in $(expand_sequence "$CPU_LIST" " ")
|
|
do
|
|
# Check that we are not setting PM QoS policy for non-existing CPU
|
|
if [ "$CPU_NUM" -lt "0" ] || [ "$CPU_NUM" -ge "$NUMBER_OF_CPUS" ]; then
|
|
log_error "CPU number ${CPU_NUM} is invalid, available CPUs are 0-${NUMBER_OF_CPUS-1}"
|
|
exit 1
|
|
fi
|
|
|
|
# Obtain CPU wakeup latencies for all C-states available starting from operating state to deepest sleep
|
|
declare -a LIMITS=()
|
|
LIMITS+=($(cat /sys/devices/system/cpu/cpu${CPU_NUM}/cpuidle/state*/latency 2>/dev/null | xargs | sort))
|
|
if [ ${#LIMITS[@]} -eq 0 ]; then
|
|
log_debug "Failed to get PM QoS latency limits for CPU ${CPU_NUM}"
|
|
fi
|
|
|
|
# Select appropriate CPU wakeup latency based on "low" or "high" policy
|
|
case "${POLICY}" in
|
|
"low")
|
|
# Get first sleep state for "low" policy
|
|
if [ ${#LIMITS[@]} -eq 0 ]; then
|
|
LATENCY=1
|
|
else
|
|
LATENCY=${LIMITS[1]}
|
|
fi
|
|
;;
|
|
"high")
|
|
# Get deepest sleep state for "high" policy
|
|
if [ ${#LIMITS[@]} -eq 0 ]; then
|
|
LATENCY=1000
|
|
else
|
|
LATENCY=${LIMITS[${#LIMITS[@]}-1]}
|
|
fi
|
|
;;
|
|
*)
|
|
log_error "Policy is invalid, can be either low or high"
|
|
exit 1
|
|
esac
|
|
|
|
# Set the latency for paricular CPU
|
|
echo ${LATENCY} > /sys/devices/system/cpu/cpu${CPU_NUM}/power/pm_qos_resume_latency_us 2>/dev/null
|
|
RET_VAL=$?
|
|
if [ ${RET_VAL} -ne 0 ]; then
|
|
log_error "Failed to set PM QoS latency for CPU ${CPU_NUM}, rc=${RET_VAL}"
|
|
continue
|
|
else
|
|
log_debug "Succesfully set PM QoS latency for CPU ${CPU_NUM}, rc=${RET_VAL}"
|
|
STATUS=0
|
|
fi
|
|
done
|
|
|
|
exit ${STATUS}
|