Re: [PATCH v6 0/5] selftests/resctrl: Add non-contiguous CBMs in Intel CAT selftest

[Shuah Khan <skhan@linuxfoundation.org>]

On 2/26/24 02:28, Maciej Wieczor-Retman wrote:
> Hi Shuah,
> 
> On 2024-02-23 at 15:37:11 -0700, Shuah Khan wrote:
>>
>> Hi Reinette,
>>
>> Okay ran a quick test. Why does this test leave "/sys/fs/resctrl"
>> mounted when it exits. Can we fix this to unmount before the test
>> exits?
> 
> I also wasn't able to reproduce this unmounting issue:
> - with unmounted resctrl before test:
> 
> 	[/root]# ls /sys/fs/resctrl/
> 	[/root]#
> 	[/root]# ./resctrl_tests -t L3_NONCONT_CAT
> 	TAP version 13
> 	# Pass: Check kernel supports resctrl filesystem
> 	# Pass: Check resctrl mountpoint "/sys/fs/resctrl" exists
> 	# resctrl filesystem not mounted
> 	# dmesg: [   12.502941] resctrl: L3 allocation detected
> 	# dmesg: [   12.507134] resctrl: MB allocation detected
> 	# dmesg: [   12.511315] resctrl: L3 monitoring detected
> 	1..1
> 	# Starting L3_NONCONT_CAT test ...
> 	# Mounting resctrl to "/sys/fs/resctrl"
> 	# Write schema "L3:1=3f" to resctrl FS
> 	# Write schema "L3:1=f0f" to resctrl FS # write() failed : Invalid argument
> 	# Non-contiguous CBMs not supported and write of non-contiguous CBM failed as expected
> 	ok 1 L3_NONCONT_CAT: test
> 	# Totals: pass:1 fail:0 xfail:0 xpass:0 skip:0 error:0
> 	[/root]# ls /sys/fs/resctrl/
> 	[/root]#
> 
> And with mounted before test:
> 
> 	[/root]# ls /sys/fs/resctrl/
> 	[/root]#
> 	[/root]# mount -t resctrl resctrl /sys/fs/resctrl
> 	[/root]# ls /sys/fs/resctrl/
> 	cpus  cpus_list  info  mode  mon_data  mon_groups  schemata  size  tasks
> 	[/root]# ./resctrl_tests -t L3_NONCONT_CAT
> 	TAP version 13
> 	# Pass: Check kernel supports resctrl filesystem
> 	# Pass: Check resctrl mountpoint "/sys/fs/resctrl" exists
> 	# resctrl filesystem is mounted
> 	# dmesg: [   12.502941] resctrl: L3 allocation detected
> 	# dmesg: [   12.507134] resctrl: MB allocation detected
> 	# dmesg: [   12.511315] resctrl: L3 monitoring detected
> 	1..1
> 	# Starting L3_NONCONT_CAT test ...
> 	# Mounting resctrl to "/sys/fs/resctrl"
> 	# Write schema "L3:1=3f" to resctrl FS
> 	# Write schema "L3:1=f0f" to resctrl FS # write() failed : Invalid argument
> 	# Non-contiguous CBMs not supported and write of non-contiguous CBM failed as expected
> 	ok 1 L3_NONCONT_CAT: test
> 	# Totals: pass:1 fail:0 xfail:0 xpass:0 skip:0 error:0
> 	[/root]# ls /sys/fs/resctrl/
> 	[/root]#
> 
> Looking at the code there is an unmounting function called after each test (at
> the end of run_single_test() inside of test_cleanup()). The non-contiguous test
> also doesn't write any data into a temp file so no additional cleanup is
> necessary.
> 


Looks fine. Thanks for the clarification.

thanks,
-- Shuah