Re: [dpdk-stable] [dpdk-dev] [PATCH v3 2/3] test/power: fix a bug in cpufreq autotest

[Richael Zhuang <Richael.Zhuang@arm.com>]

> -----Original Message-----
> From: Burakov, Anatoly <anatoly.burakov@intel.com>
> Sent: Thursday, April 8, 2021 10:56 PM
> To: Richael Zhuang <Richael.Zhuang@arm.com>; dev@dpdk.org
> Cc: lukaszx.krakowiak@intel.com; stable@dpdk.org; David Hunt
> <david.hunt@intel.com>
> Subject: Re: [dpdk-dev] [PATCH v3 2/3] test/power: fix a bug in cpufreq
> autotest
> 
> On 08-Apr-21 3:10 AM, Richael Zhuang wrote:
> > Hi,
> > Thanks for your comments.
> > My change  is to make  the check_power_turbo()  to continue only when
> rte_power_turbo_status(TEST_POWER_LCORE_ID) returns 1 which means
> turbo is available.
> 
> Sure, but the code reads like if the turbo status isn't available, then the code
> just treats it as "unsupported", where in reality it could've been supported,
> but failed for some other reason.
> 
Hi Anatoly,
I'm thinking if it's better to abandon this patch.
 For KVM case, although rte_power_turbo_status() returns -ENOTSUP, the check should continue  because rte_power_freq_enable_turbo() and  rte_power_freq_disable_turbo() are  available in power_kvm_vm.c .

Originally I added this patch considering there is case that turbo is not supported on some platforms and all turbo related functions return -ENOTSUP.   

Best Regards
> >
> > -----Original Message-----
> > From: Burakov, Anatoly <anatoly.burakov@intel.com>
> > Sent: Wednesday, April 7, 2021 5:59 PM
> > To: Richael Zhuang <Richael.Zhuang@arm.com>; dev@dpdk.org
> > Cc: lukaszx.krakowiak@intel.com; stable@dpdk.org; David Hunt
> > <david.hunt@intel.com>
> > Subject: Re: [dpdk-dev] [PATCH v3 2/3] test/power: fix a bug in
> > cpufreq autotest
> >
> > On 07-Apr-21 8:46 AM, Richael Zhuang wrote:
> >> For platforms that don't support turbo boost,rte_power_turbo_status()
> >> returns "-ENOTSUP" (like power_kvm_vm_turbo_status()). So don't allow
> >> check_power_turbo() to continue if
> >> rte_power_turbo_status(TEST_POWER_LCORE_ID)!=1
> >>
> >> Fixes: aeaeaf5f2d62 ("test/power: add cases for turbo feature")
> >> Cc: lukaszx.krakowiak@intel.com
> >> Cc: stable@dpdk.org
> >>
> >> Signed-off-by: Richael Zhuang <richael.zhuang@arm.com>
> >> ---
> >>    app/test/test_power_cpufreq.c | 2 +-
> >>    1 file changed, 1 insertion(+), 1 deletion(-)
> >>
> >> diff --git a/app/test/test_power_cpufreq.c
> >> b/app/test/test_power_cpufreq.c index 1f4d8bb05..cda74bd8a 100644
> >> --- a/app/test/test_power_cpufreq.c
> >> +++ b/app/test/test_power_cpufreq.c
> >> @@ -386,7 +386,7 @@ check_power_turbo(void)
> >>    {
> >>    int ret;
> >>
> >> -if (rte_power_turbo_status(TEST_POWER_LCORE_ID) == 0) {
> >> +if (rte_power_turbo_status(TEST_POWER_LCORE_ID) != 1) {
> >>    printf("Turbo not available on lcore %u, skipping test\n",
> >>    TEST_POWER_LCORE_ID);
> >>    return 0;
> >>
> >
> > If what you're really checking is -ENOTSUP, maybe check for that?
> > Because otherwise it seems like you're making unwarranted assumptions
> about why the call failed...
> >
> > --
> > Thanks,
> > Anatoly
> >
> 
> 
> --
> Thanks,
> Anatoly