| Message ID | 20200707152917.10652-3-psampat@linux.ibm.com (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
| Series | Selftest for cpuidle latency measurement | expand |
On 7/7/20 9:29 AM, Pratik Rajesh Sampat wrote: > This patch adds support to trace IPI based and timer based wakeup > latency from idle states > > Latches onto the test-cpuidle_latency kernel module using the debugfs > interface to send IPIs or schedule a timer based event, which in-turn > populates the debugfs with the latency measurements. > > Currently for the IPI and timer tests; first disable all idle states > and then test for latency measurements incrementally enabling each state > > Signed-off-by: Pratik Rajesh Sampat <psampat@linux.ibm.com> > --- > tools/testing/selftests/Makefile | 1 + > tools/testing/selftests/cpuidle/Makefile | 6 + > tools/testing/selftests/cpuidle/cpuidle.sh | 240 +++++++++++++++++++++ > tools/testing/selftests/cpuidle/settings | 1 + > 4 files changed, 248 insertions(+) > create mode 100644 tools/testing/selftests/cpuidle/Makefile > create mode 100755 tools/testing/selftests/cpuidle/cpuidle.sh > create mode 100644 tools/testing/selftests/cpuidle/settings > > diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile > index 1195bd85af38..ab6cf51f3518 100644 > --- a/tools/testing/selftests/Makefile > +++ b/tools/testing/selftests/Makefile > @@ -7,6 +7,7 @@ TARGETS += capabilities > TARGETS += cgroup > TARGETS += clone3 > TARGETS += cpufreq > +TARGETS += cpuidle > TARGETS += cpu-hotplug > TARGETS += drivers/dma-buf > TARGETS += efivarfs > diff --git a/tools/testing/selftests/cpuidle/Makefile b/tools/testing/selftests/cpuidle/Makefile > new file mode 100644 > index 000000000000..72fd5d2e974d > --- /dev/null > +++ b/tools/testing/selftests/cpuidle/Makefile > @@ -0,0 +1,6 @@ > +# SPDX-License-Identifier: GPL-2.0 > +all: > + > +TEST_PROGS := cpuidle.sh > + > +include ../lib.mk > diff --git a/tools/testing/selftests/cpuidle/cpuidle.sh b/tools/testing/selftests/cpuidle/cpuidle.sh > new file mode 100755 > index 000000000000..11666fe47c34 > --- /dev/null > +++ b/tools/testing/selftests/cpuidle/cpuidle.sh > @@ -0,0 +1,240 @@ > +#!/bin/bash > +# SPDX-License-Identifier: GPL-2.0 > + > +LOG=cpuidle.log > +MODULE=/lib/modules/$(uname -r)/kernel/drivers/cpuidle/test-cpuidle_latency.ko > + > +helpme() > +{ > + printf "Usage: $0 [-h] [-todg args] > + [-h <help>] > + [-m <location of the module>] > + [-o <location of the output>] > + \n" > + exit 2 > +} > + > +parse_arguments() > +{ > + while getopts ht:m:o: arg > + do > + case $arg in > + h) # --help > + helpme > + ;; > + m) # --mod-file > + MODULE=$OPTARG > + ;; > + o) # output log files > + LOG=$OPTARG > + ;; > + \?) > + helpme > + ;; > + esac > + done > +} > + > +ins_mod() > +{ > + if [ ! -f "$MODULE" ]; then > + printf "$MODULE module does not exist. Exitting\n" > + exit 2 Please use ksft_skip code to indicate the test is being skipped. > + fi > + printf "Inserting $MODULE module\n\n" > + insmod $MODULE > + if [ $? != 0 ]; then > + printf "Insmod $MODULE failed\n" > + exit 2 This is fine since you expect to be able to load the module. > + fi > +} > + > +compute_average() > +{ > + arr=("$@") > + sum=0 > + size=${#arr[@]} > + for i in "${arr[@]}" > + do > + sum=$((sum + i)) > + done > + avg=$((sum/size)) > +} > + > +# Disable all stop states > +disable_idle() > +{ > + for ((cpu=0; cpu<NUM_CPUS; cpu++)) > + do > + for ((state=0; state<NUM_STATES; state++)) > + do > + echo 1 > /sys/devices/system/cpu/cpu$cpu/cpuidle/state$state/disable > + done > + done > +} > + > +# Enable the idle state supplied > +# $1: State to enable > +enable_state() > +{ > + for ((cpu=0; cpu<NUM_CPUS; cpu++)) > + do > + echo 0 > /sys/devices/system/cpu/cpu$cpu/cpuidle/state$1/disable > + done > +} > + > +# Extract latency in microseconds and convert to nanoseconds > +extract_latency() > +{ > + for ((state=0; state<NUM_STATES; state++)) > + do > + latency=$(($(cat /sys/devices/system/cpu/cpu0/cpuidle/state$state/latency) * 1000)) > + latency_arr+=($latency) > + done > +} > + > +# Run the IPI test > +# $1 run for baseline - busy cpu or regular environment > +# $2 destination cpu > +ipi_test_once() > +{ > + dest_cpu=$2 > + if [ "$1" = "baseline" ]; then > + # Keep the CPU busy > + taskset -c $dest_cpu yes "" > /dev/null & > + yes_pid=$! > + fi > + taskset 0x1 echo $dest_cpu > /sys/kernel/debug/latency_test/ipi_cpu_dest > + ipi_latency=$(cat /sys/kernel/debug/latency_test/ipi_latency_ns) > + src_cpu=$(cat /sys/kernel/debug/latency_test/ipi_cpu_src) > + if [ "$1" = "baseline" ]; then > + kill $yes_pid > + wait $yes_pid 2>/dev/null > + fi > +} > + > +# Incrementally Enable idle states one by one and compute the latency > +run_ipi_tests() > +{ > + extract_latency > + disable_idle > + declare -a avg_arr > + declare -a baseline_avg_array > + > + echo -e "--IPI Latency Test---" >> $LOG > + for ((state=0; state<NUM_STATES; state++)) > + do > + echo -e "---Enabling state: $state---" >> $LOG > + enable_state $state > + printf "%s %10s %12s %12s\n" "SRC_CPU" "DEST_CPU" "Base_IPI_Latency(ns)" "IPI_Latency(ns)" >> $LOG > + unset avg_arr > + unset baseline_avg_arr > + for ((cpu=0; cpu<NUM_CPUS; cpu++)) > + do > + # Running IPI test and logging results > + ipi_test_once "baseline" $cpu > + baseline_ipi_latency=$ipi_latency > + ipi_test_once "test" $cpu > + printf "%-3s %10s %12s %18s\n" $src_cpu $cpu $baseline_ipi_latency $ipi_latency >> $LOG > + avg_arr+=($ipi_latency) > + baseline_avg_arr+=($baseline_ipi_latency) > + done > + compute_average "${avg_arr[@]}" > + local avg_latency=$avg > + compute_average "${baseline_avg_arr[@]}" > + local baseline_avg_latency=$avg > + echo -e "Expected IPI latency(ns): ${latency_arr[$state]}" >> $LOG > + echo -e "Baseline Average IPI latency(ns): $baseline_avg_latency" >> $LOG > + echo -e "Observed Average IPI latency(ns): $avg_latency" >> $LOG > + done > +} > + > +# Extract the residency in microseconds and convert to nanoseconds. > +# Add 100 ns so that the timer stays for a little longer than the residency > +extract_residency() > +{ > + for ((state=0; state<NUM_STATES; state++)) > + do > + residency=$(($(cat /sys/devices/system/cpu/cpu0/cpuidle/state$state/residency) * 1000 + 200)) > + residency_arr+=($residency) > + done > +} > + > +# Run the Timeout test > +# $1 run for baseline - busy cpu or regular environment > +# $2 destination cpu > +# $3 timeout > +timeout_test_once() > +{ > + dest_cpu=$2 > + if [ "$1" = "baseline" ]; then > + # Keep the CPU busy > + taskset -c $dest_cpu yes "" > /dev/null & > + yes_pid=$! > + fi > + taskset -c $dest_cpu echo $3 > /sys/kernel/debug/latency_test/timeout_expected_ns > + sleep 0.1 > + timeout_diff=$(cat /sys/kernel/debug/latency_test/timeout_diff_ns) > + src_cpu=$(cat /sys/kernel/debug/latency_test/timeout_cpu_src) > + if [ "$1" = "baseline" ]; then > + kill $yes_pid > + wait $yes_pid 2>/dev/null > + fi > +} > + > +run_timeout_tests() > +{ > + extract_residency > + disable_idle > + declare -a avg_arr > + declare -a baseline_avg_arr > + echo -e "\n--Timeout Latency Test--" >> $LOG > + > + for ((state=0; state<NUM_STATES; state++)) > + do > + echo -e "---Enabling state: $state---" >> $LOG > + enable_state $state > + printf "%s %10s %10s\n" "Wakeup_src" "Baseline_delay(ns)" "Delay(ns)" >> $LOG > + unset avg_arr > + unset baseline_avg_arr > + for ((cpu=0; cpu<NUM_CPUS; cpu++)) > + do > + timeout_test_once "baseline" $cpu ${residency_arr[$state]} > + local baseline_timeout_diff=$timeout_diff > + timeout_test_once "test" $cpu ${residency_arr[$state]} > + printf "%-3s %13s %18s\n" $src_cpu $baseline_timeout_diff $timeout_diff >> $LOG > + avg_arr+=($timeout_diff) > + baseline_avg_arr+=($baseline_timeout_diff) > + done > + compute_average "${baseline_avg_arr[@]}" > + local baseline_avg=$avg > + compute_average "${avg_arr[@]}" > + echo -e "Expected timeout(ns): ${residency_arr[$state]}" >> $LOG > + echo -e "Baseline Average timeout diff(ns): $baseline_avg" >> $LOG > + echo -e "Observed Average timeout diff(ns): $avg" >> $LOG > + done > +} > + > +declare -a residency_arr > +declare -a latency_arr > + > +# Parse arguments > +parse_arguments $@ > + > +rm -f $LOG > +touch $LOG > +NUM_CPUS=$(nproc --all) > +NUM_STATES=$(ls -1 /sys/devices/system/cpu/cpu0/cpuidle/ | wc -l) > + > +# Insert the module > +ins_mod $MODULE > + > +printf "Started IPI latency tests\n" > +run_ipi_tests > + > +printf "Started Timer latency tests\n" > +run_timeout_tests > + > +printf "Removing $MODULE module\n" > +printf "Output logged at: $LOG\n" > +rmmod $MODULE > diff --git a/tools/testing/selftests/cpuidle/settings b/tools/testing/selftests/cpuidle/settings > new file mode 100644 > index 000000000000..e7b9417537fb > --- /dev/null > +++ b/tools/testing/selftests/cpuidle/settings > @@ -0,0 +1 @@ > +timeout=0 > thanks, -- Shuah
[..snip..] >> + >> +ins_mod() >> +{ >> + if [ ! -f "$MODULE" ]; then >> + printf "$MODULE module does not exist. Exitting\n" >> + exit 2 > > Please use ksft_skip code to indicate the test is being skipped. > Sure thing I'll use ksft_skip exit code instead. >> + fi >> + printf "Inserting $MODULE module\n\n" >> + insmod $MODULE >> + if [ $? != 0 ]; then >> + printf "Insmod $MODULE failed\n" >> + exit 2 > > This is fine since you expect to be able to load the module. > Thanks for the review. Pratik [..snip..] >> > > thanks, > -- Shuah
diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile index 1195bd85af38..ab6cf51f3518 100644 --- a/tools/testing/selftests/Makefile +++ b/tools/testing/selftests/Makefile @@ -7,6 +7,7 @@ TARGETS += capabilities TARGETS += cgroup TARGETS += clone3 TARGETS += cpufreq +TARGETS += cpuidle TARGETS += cpu-hotplug TARGETS += drivers/dma-buf TARGETS += efivarfs diff --git a/tools/testing/selftests/cpuidle/Makefile b/tools/testing/selftests/cpuidle/Makefile new file mode 100644 index 000000000000..72fd5d2e974d --- /dev/null +++ b/tools/testing/selftests/cpuidle/Makefile @@ -0,0 +1,6 @@ +# SPDX-License-Identifier: GPL-2.0 +all: + +TEST_PROGS := cpuidle.sh + +include ../lib.mk diff --git a/tools/testing/selftests/cpuidle/cpuidle.sh b/tools/testing/selftests/cpuidle/cpuidle.sh new file mode 100755 index 000000000000..11666fe47c34 --- /dev/null +++ b/tools/testing/selftests/cpuidle/cpuidle.sh @@ -0,0 +1,240 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 + +LOG=cpuidle.log +MODULE=/lib/modules/$(uname -r)/kernel/drivers/cpuidle/test-cpuidle_latency.ko + +helpme() +{ + printf "Usage: $0 [-h] [-todg args] + [-h <help>] + [-m <location of the module>] + [-o <location of the output>] + \n" + exit 2 +} + +parse_arguments() +{ + while getopts ht:m:o: arg + do + case $arg in + h) # --help + helpme + ;; + m) # --mod-file + MODULE=$OPTARG + ;; + o) # output log files + LOG=$OPTARG + ;; + \?) + helpme + ;; + esac + done +} + +ins_mod() +{ + if [ ! -f "$MODULE" ]; then + printf "$MODULE module does not exist. Exitting\n" + exit 2 + fi + printf "Inserting $MODULE module\n\n" + insmod $MODULE + if [ $? != 0 ]; then + printf "Insmod $MODULE failed\n" + exit 2 + fi +} + +compute_average() +{ + arr=("$@") + sum=0 + size=${#arr[@]} + for i in "${arr[@]}" + do + sum=$((sum + i)) + done + avg=$((sum/size)) +} + +# Disable all stop states +disable_idle() +{ + for ((cpu=0; cpu<NUM_CPUS; cpu++)) + do + for ((state=0; state<NUM_STATES; state++)) + do + echo 1 > /sys/devices/system/cpu/cpu$cpu/cpuidle/state$state/disable + done + done +} + +# Enable the idle state supplied +# $1: State to enable +enable_state() +{ + for ((cpu=0; cpu<NUM_CPUS; cpu++)) + do + echo 0 > /sys/devices/system/cpu/cpu$cpu/cpuidle/state$1/disable + done +} + +# Extract latency in microseconds and convert to nanoseconds +extract_latency() +{ + for ((state=0; state<NUM_STATES; state++)) + do + latency=$(($(cat /sys/devices/system/cpu/cpu0/cpuidle/state$state/latency) * 1000)) + latency_arr+=($latency) + done +} + +# Run the IPI test +# $1 run for baseline - busy cpu or regular environment +# $2 destination cpu +ipi_test_once() +{ + dest_cpu=$2 + if [ "$1" = "baseline" ]; then + # Keep the CPU busy + taskset -c $dest_cpu yes "" > /dev/null & + yes_pid=$! + fi + taskset 0x1 echo $dest_cpu > /sys/kernel/debug/latency_test/ipi_cpu_dest + ipi_latency=$(cat /sys/kernel/debug/latency_test/ipi_latency_ns) + src_cpu=$(cat /sys/kernel/debug/latency_test/ipi_cpu_src) + if [ "$1" = "baseline" ]; then + kill $yes_pid + wait $yes_pid 2>/dev/null + fi +} + +# Incrementally Enable idle states one by one and compute the latency +run_ipi_tests() +{ + extract_latency + disable_idle + declare -a avg_arr + declare -a baseline_avg_array + + echo -e "--IPI Latency Test---" >> $LOG + for ((state=0; state<NUM_STATES; state++)) + do + echo -e "---Enabling state: $state---" >> $LOG + enable_state $state + printf "%s %10s %12s %12s\n" "SRC_CPU" "DEST_CPU" "Base_IPI_Latency(ns)" "IPI_Latency(ns)" >> $LOG + unset avg_arr + unset baseline_avg_arr + for ((cpu=0; cpu<NUM_CPUS; cpu++)) + do + # Running IPI test and logging results + ipi_test_once "baseline" $cpu + baseline_ipi_latency=$ipi_latency + ipi_test_once "test" $cpu + printf "%-3s %10s %12s %18s\n" $src_cpu $cpu $baseline_ipi_latency $ipi_latency >> $LOG + avg_arr+=($ipi_latency) + baseline_avg_arr+=($baseline_ipi_latency) + done + compute_average "${avg_arr[@]}" + local avg_latency=$avg + compute_average "${baseline_avg_arr[@]}" + local baseline_avg_latency=$avg + echo -e "Expected IPI latency(ns): ${latency_arr[$state]}" >> $LOG + echo -e "Baseline Average IPI latency(ns): $baseline_avg_latency" >> $LOG + echo -e "Observed Average IPI latency(ns): $avg_latency" >> $LOG + done +} + +# Extract the residency in microseconds and convert to nanoseconds. +# Add 100 ns so that the timer stays for a little longer than the residency +extract_residency() +{ + for ((state=0; state<NUM_STATES; state++)) + do + residency=$(($(cat /sys/devices/system/cpu/cpu0/cpuidle/state$state/residency) * 1000 + 200)) + residency_arr+=($residency) + done +} + +# Run the Timeout test +# $1 run for baseline - busy cpu or regular environment +# $2 destination cpu +# $3 timeout +timeout_test_once() +{ + dest_cpu=$2 + if [ "$1" = "baseline" ]; then + # Keep the CPU busy + taskset -c $dest_cpu yes "" > /dev/null & + yes_pid=$! + fi + taskset -c $dest_cpu echo $3 > /sys/kernel/debug/latency_test/timeout_expected_ns + sleep 0.1 + timeout_diff=$(cat /sys/kernel/debug/latency_test/timeout_diff_ns) + src_cpu=$(cat /sys/kernel/debug/latency_test/timeout_cpu_src) + if [ "$1" = "baseline" ]; then + kill $yes_pid + wait $yes_pid 2>/dev/null + fi +} + +run_timeout_tests() +{ + extract_residency + disable_idle + declare -a avg_arr + declare -a baseline_avg_arr + echo -e "\n--Timeout Latency Test--" >> $LOG + + for ((state=0; state<NUM_STATES; state++)) + do + echo -e "---Enabling state: $state---" >> $LOG + enable_state $state + printf "%s %10s %10s\n" "Wakeup_src" "Baseline_delay(ns)" "Delay(ns)" >> $LOG + unset avg_arr + unset baseline_avg_arr + for ((cpu=0; cpu<NUM_CPUS; cpu++)) + do + timeout_test_once "baseline" $cpu ${residency_arr[$state]} + local baseline_timeout_diff=$timeout_diff + timeout_test_once "test" $cpu ${residency_arr[$state]} + printf "%-3s %13s %18s\n" $src_cpu $baseline_timeout_diff $timeout_diff >> $LOG + avg_arr+=($timeout_diff) + baseline_avg_arr+=($baseline_timeout_diff) + done + compute_average "${baseline_avg_arr[@]}" + local baseline_avg=$avg + compute_average "${avg_arr[@]}" + echo -e "Expected timeout(ns): ${residency_arr[$state]}" >> $LOG + echo -e "Baseline Average timeout diff(ns): $baseline_avg" >> $LOG + echo -e "Observed Average timeout diff(ns): $avg" >> $LOG + done +} + +declare -a residency_arr +declare -a latency_arr + +# Parse arguments +parse_arguments $@ + +rm -f $LOG +touch $LOG +NUM_CPUS=$(nproc --all) +NUM_STATES=$(ls -1 /sys/devices/system/cpu/cpu0/cpuidle/ | wc -l) + +# Insert the module +ins_mod $MODULE + +printf "Started IPI latency tests\n" +run_ipi_tests + +printf "Started Timer latency tests\n" +run_timeout_tests + +printf "Removing $MODULE module\n" +printf "Output logged at: $LOG\n" +rmmod $MODULE diff --git a/tools/testing/selftests/cpuidle/settings b/tools/testing/selftests/cpuidle/settings new file mode 100644 index 000000000000..e7b9417537fb --- /dev/null +++ b/tools/testing/selftests/cpuidle/settings @@ -0,0 +1 @@ +timeout=0
This patch adds support to trace IPI based and timer based wakeup latency from idle states Latches onto the test-cpuidle_latency kernel module using the debugfs interface to send IPIs or schedule a timer based event, which in-turn populates the debugfs with the latency measurements. Currently for the IPI and timer tests; first disable all idle states and then test for latency measurements incrementally enabling each state Signed-off-by: Pratik Rajesh Sampat <psampat@linux.ibm.com> --- tools/testing/selftests/Makefile | 1 + tools/testing/selftests/cpuidle/Makefile | 6 + tools/testing/selftests/cpuidle/cpuidle.sh | 240 +++++++++++++++++++++ tools/testing/selftests/cpuidle/settings | 1 + 4 files changed, 248 insertions(+) create mode 100644 tools/testing/selftests/cpuidle/Makefile create mode 100755 tools/testing/selftests/cpuidle/cpuidle.sh create mode 100644 tools/testing/selftests/cpuidle/settings