Re: [PATCH 1/1] genirq/cpuhotplug: Bump debugging information print down to KERN_DEBUG

From: Thomas Gleixner
Date: Wed Aug 11 2021 - 08:08:59 EST


On Wed, Aug 11 2021 at 08:57, Lee Jones wrote:
> On Tue, 10 Aug 2021, Thomas Gleixner wrote:
>> > @@ -42,7 +42,7 @@ static inline bool irq_needs_fixup(struct irq_data *d)
>> > * If this happens then there was a missed IRQ fixup at some
>> > * point. Warn about it and enforce fixup.
>> > */
>> > - pr_warn("Eff. affinity %*pbl of IRQ %u contains only offline CPUs after offlining CPU %u\n",
>>
>> This one is clearly a warning as this should not happen. See the
>> comments around that.
>>
>> > + pr_debug("Eff. affinity %*pbl of IRQ %u contains only offline CPUs after offlining CPU %u\n",
>> > cpumask_pr_args(m), d->irq, cpu);
>> > return true;
>> > }
>> > @@ -166,7 +166,7 @@ void irq_migrate_all_off_this_cpu(void)
>> > raw_spin_unlock(&desc->lock);
>> >
>> > if (affinity_broken) {
>> > - pr_warn_ratelimited("IRQ %u: no longer affine to CPU%u\n",
>> > + pr_debug_ratelimited("IRQ %u: no longer affine to CPU%u\n",
>> > irq, smp_processor_id());
>>
>> Maybe, but distro people might have opinions on that.
>
> The trouble is, even if these are real warnings, they have an affect
> on performance on real products. To the point where so much logging
> builds up during pre-release testing, that it sets off the watchdog(s)
> on some high profile consumer devices.

I'm fine with making the second one debug, but the first one really
should not trigger at all.

Thanks,

tglx