Re: çå: [RFC] irq: Skip printing irq when desc->action is null even if any_count is not zero

From: Thomas Gleixner
Date: Thu Jan 23 2020 - 07:34:47 EST


Chao,

"liuchao (CR)" <liuchao173@xxxxxxxxxx> writes:
> On Thu, Jan 23, 2020 at 03:29AM +0800, Neil Horman wrote:
>> > I'm not opposed to suppress the output, but I really want the opinion
>> > of the irqbalance maintainers on that.
>
> Irqbalance is an example. I mean, when this happens, users who cat /proc/interrupts
> may be confused about where the interrupt came from and what it was used for.
> People who use Linux may not understand the principle of this. They are not sure
> whether this is a problem of the system or not.

Well, this has been that way for 20+ years and so far nobody got
confused. If it's not documented then we should do so.

>> Actually, irqbalance ignores the trailing irq name (or it should at least), so you
>> should be able to drop that portion of /proc/irqbalance, though I cant speak for
>> any other users of it.
>
> If irq isn't removed from /proc/interrups, it will still be parsed in
> collect_full_irq_list and parse_proc_interrupts.

Sure, and why is that a problem? Again, this is really historic behaviour.

> irq_name is used in guess_arm_irq_hints.

That's a problem of guess_arm_irq_hints() then.

Again, I'm not against supressing such lines in general, but I want to
make sure that no tool depends on that information.

Thanks,

tglx