Hi Gautham, Thanks for the review.
On 20/07/20 11:22 am, Gautham R Shenoy wrote:
Hi Pratik,
On Fri, Jul 17, 2020 at 02:48:01PM +0530, 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 <psam...@linux.ibm.com>
A few comments below.
---
tools/testing/selftests/Makefile | 1 +
tools/testing/selftests/cpuidle/Makefile | 6 +
tools/testing/selftests/cpuidle/cpuidle.sh | 257 +++++++++++++++++++++
tools/testing/selftests/cpuidle/settings | 1 +
4 files changed, 265 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
[..skip..]
+
+ins_mod()
+{
+ if [ ! -f "$MODULE" ]; then
+ printf "$MODULE module does not exist. Exitting\n"
If the module has been compiled into the kernel (due to a
localyesconfig, for instance), then it is unlikely that we will find
it in /lib/modules. Perhaps you want to check if the debugfs
directories created by the module exist, and if so, print a message
saying that the modules is already loaded or some such?
That's a good idea. I can can grep for this module within /proc/modules
and not insert it, if it is already there
+ exit $ksft_skip
+ fi
+ printf "Inserting $MODULE module\n\n"
+ insmod $MODULE
+ if [ $? != 0 ]; then
+ printf "Insmod $MODULE failed\n"
+ exit $ksft_skip
+ fi
+}
+
+compute_average()
+{
+ arr=("$@")
+ sum=0
+ size=${#arr[@]}
+ for i in "${arr[@]}"
+ do
+ sum=$((sum + i))
+ done
+ avg=$((sum/size))
It would be good to assert that "size" isn't 0 here.
Sure
+}
+
+# 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
So, on offlined CPUs, we won't see
/sys/devices/system/cpu/cpu$cpu/cpuidle/state$state directory. You
should probably perform this operation only on online CPUs.
Right. I should make CPU operations only on online CPUs all over the script
[..snip..]
Thanks
Pratik
