From mboxrd@z Thu Jan 1 00:00:00 1970 From: rjw@rjwysocki.net (Rafael J. Wysocki) Date: Wed, 23 Jul 2014 13:58:55 +0200 Subject: [PATCH v2] cpufreq: tests: Providing cpufreq regression test In-Reply-To: References: <1405678985-21677-1-git-send-email-l.majewski@samsung.com> <20140723093824.5e51918f@amdc2363> Message-ID: <3433055.CnoZBIqQNF@vostro.rjw.lan> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Wednesday, July 23, 2014 02:19:54 PM Viresh Kumar wrote: > On 23 July 2014 13:08, Lukasz Majewski wrote: > > Do you want to say that we have enough tests and we don't need more ? > > No. We don't have any tests at all :) > > > I always thought that we shall have as much regression tests as > > possible. > > Yeah, tests are welcomed but the question is where should they get added. > Don't know if its common to add tests directly to kernel. Yes, it is. > And also if the test is really good, not discouraging your work. > > >> On 21 July 2014 12:32, Lukasz Majewski wrote: > >> > This commit adds first regression test "cpufreq_freq_test.sh" for > >> > the cpufreq subsystem. > >> > >> That's not enough, Tell us why we should continue reading this mail.. > > > > Hmm... If "regression" and "test" don't catch the attention of a > > diligent maintainer, then I cannot do much more to encourage him to > > read the whole e-mail :-) > > What I meant to say was, your subject and body must be good enough > to answer most of the things. You don't have to tell much about the > implementation but other things should be pretty clear from logs. > > Your current logs are quite short for something that's not a normal practice. > > > I can imagine that maintainers are very busy, therefore I've prepared > > README file with detailed description of the script operation. > > Yeah, a README is welcomed and would be useful for users as well.. > > >> I couldn't make out the purpose of this test and why we need it. How > >> do we ensure that "cpufreq attributes exported by sysfs are exposing > >> correct values"? > > > > First of all the cpufreq attributes are part of the subsystem API. > > There are systems which actually depend on them, so we would be better > > off to test if they work as intended. > > > > Secondly, the test takes those values and then with use of other > > attribute enforce the value, which is then read via cat'ing > > cpufreq_cur_freq. If any of the attributes is wrong then we will spot > > the error immediately. > > Shouldn't you use userspace governor then instead of performance? > And then we don't need the gzip stuff at all. We can just set it to the > right freq and get current freq to see if it matches? > > And now that we are starting to get tests added into the kernel (will still > wait to see what Rafael has to advice), we better think of the way these > are going to get added. Probably a single script with parameters like > what to test? I've had a look at the Lukasz' patch in the first iteration and I'm going to look at it again shortly. At this point I can only say that it should be clear to the user of the script what is tested, as well as what "success" and what "failure" mean. -- I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center.