Re: [PATCH v3] PCI: hotplug: Add a generic RAS tracepoint for hotplug event

[Shuai Xue <xueshuai@linux.alibaba.com>]

在 2024/11/21 21:43, Steven Rostedt 写道:
> On Thu, 21 Nov 2024 19:34:31 +0800
> Shuai Xue <xueshuai@linux.alibaba.com> wrote:
> 
>> Sure, I can reorganize the directory. You have two optional proposals:
>>
>> 1. /sys/kernel/debug/tracing/events/pci_hp_event
> 
> I'm guessing the above has TRACING_SYSTEM = pci_hp_event ? That is, the
> above is a system and not an event.
> 
>> 2. /sys/kernel/debug/tracing/events/pci/pci_hp_event
> 
> Whereas here, it's an event.
> 
>>
>> I personally prefer the second approach. However, I'll defer the final decision
>> to the tracing subsystem maintainer, considering their expertise and
>> familiarity with the existing conventions.
> 
> Normally the system is determined by the users of the tracing
> infrastructure and not the tracing maintainers. But I can give you some
> guidelines.
> 
> The "system" level:
> 
>    /sys/kernel/tracing/events/<system>
> 
> is just a way to group like events making it easier to enable them all at once:
> 
>   echo 1 > /sys/kernel/tracing/events/<system>/enable
> 
> or
> 
>    trace-cmd start -e <system>
> 
> The name of the "system" should be something that all the events underneath
> represent. Note, although events in two different systems can have the same
> name, it's best to try to keep them all unique. That's because if you have:
> 
> 
>   systemA/foo  and systemB/foo
> 
> If you add to the kernel command line: trace_event=foo
> it will enable both events. Although that could be fixed with: trace_event=systemA:foo
> 
> Note: trace_event=systemA  would enable all systemA events at boot.
> 
> That said, is all these events going to be related to hotplug? If so, you
> probably want "hotplug" or "hp" in the system name. If you make it just
> "pci", then it will be expected that all the events will be related to PCI
> in general.

I think Lukas is asking for a system for pci related tracepoint.

> 
> Does that help?

Yes, it really does.

> 
> -- Steve

Thanks a lot.

Best Regards,
Shuai