Message-ID: <537d3d3d-9ecc-bdd9-f703-708f6826d1f2@linuxfoundation.org>
Date:   Fri, 3 Mar 2023 13:35:10 -0700
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Subject: Re: [PATCH 1/2] selftests/kmod: increase the kmod timeout from 45 to
 165
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To:     Luis Chamberlain <mcgrof@kernel.org>
Cc:     shuah@kernel.org, linux-kselftest@vger.kernel.org,
        gregkh@linuxfoundation.org, tiwai@suse.de, tianfei.zhang@intel.com,
        russell.h.weight@intel.com, keescook@chromium.org,
        tweek@google.com, a.manzanares@samsung.com, dave@stgolabs.net,
        linux-modules@vger.kernel.org, linux-kernel@vger.kernel.org,
        Shuah Khan <skhan@linuxfoundation.org>
References: <20230206234344.2433950-1-mcgrof@kernel.org>
 <20230206234344.2433950-2-mcgrof@kernel.org>
 <b094dc23-a96d-93c4-a350-8fb92476f431@linuxfoundation.org>
 <Y/0xx0cedxlRMKpH@bombadil.infradead.org>
From:   Shuah Khan <skhan@linuxfoundation.org>
In-Reply-To: <Y/0xx0cedxlRMKpH@bombadil.infradead.org>
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Precedence: bulk

On 2/27/23 15:42, Luis Chamberlain wrote:
> On Mon, Feb 27, 2023 at 03:32:50PM -0700, Shuah Khan wrote:
>> On 2/6/23 16:43, Luis Chamberlain wrote:
>>> The default sefltests timeout is 45 seconds. If you run the kmod
>>> selftests on your own with say:
>>>
>>> ./tools/testings/selftests/kmod.sh
>>>
>>> Then the default timeout won't be in effect.
>>>
>>> I've never ran kmod selftests using the generic make wrapper
>>> (./tools/testing/selftests/run_kselftest.sh -s) util now
>>> that I have support for it on kdevops [0]. And with that the
>>> test is limitted to the default timeout which we quickly run
>>> into. Bump this up to what I see is required on 8GiB / 8 vcpu
>>> libvirt q35 guest as can be easily created now with kdevops.
>>>
>>> To run selftests with kdevops:
>>>
>>> make menuconfig # enable dedicated selftests and kmod test
>>> make
>>> make bringup
>>> make linux
>>> make selftests-kmod
>>>
>>> This ends up taking about 280 seconds now, give or take add
>>> 50 seconds more more and we end up with 350. Document the
>>> rationale.
>>>
>>> [0] https://github.com/linux-kdevops/kdevops
>>> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
>>> ---
>>>    tools/testing/selftests/kmod/settings | 4 ++++
>>>    1 file changed, 4 insertions(+)
>>>    create mode 100644 tools/testing/selftests/kmod/settings
>>>
>>> diff --git a/tools/testing/selftests/kmod/settings b/tools/testing/selftests/kmod/settings
>>> new file mode 100644
>>> index 000000000000..6fca0f1a4594
>>> --- /dev/null
>>> +++ b/tools/testing/selftests/kmod/settings
>>> @@ -0,0 +1,4 @@
>>> +# measured from a manual run:
>>> +# time ./tools/testing/selftests/kmod/kmod.sh
>>> +# Then add ~50 seconds more gracetime.
>>> +timeout=350
>>
>> Adding timeouts like this for individual tests increases the overall kselftest
>> run-time. I am not in favor of adding timeouts.
>>
>> We have to find a better way to do this.
> 
> Well if folks don't have this the test will fail, and so a false
> positive. If the goal is to have a low time timeout for "do not run
> tests past this time and do not fail if we stopped the test" then
> that seems to be likely one way to go and each test may need to be
> modified to not fail fatally in case of a special signal.
> 

We are finding more and more that timeout values are requiring
tweaks. I am in favor of coming up a way to exit the test with
a timeout condition.

thanks,
-- Shuah