Re: [PATCH v8 07/21] x86/resctrl: Add end-marker to the resctrl_event_id enum
From: James Morse
Date: Thu Apr 24 2025 - 05:15:55 EST
Hi Tony,
On 15/04/2025 19:56, Luck, Tony wrote:
> On Fri, Apr 11, 2025 at 04:42:15PM +0000, James Morse wrote:
>> The resctrl_event_id enum gives names to the counter event numbers on x86.
>> These are used directly by resctrl.
>>
>> To allow the MPAM driver to keep an array of these the size of the enum
>> needs to be known.
>>
>> Add a 'num_events' define which can be used to size an array. This isn't
>> a member of the enum to avoid updating switch statements that would
>> otherwise be missing a case.
>
> I'm adding more events in this series:
>
> https://lore.kernel.org/all/20250407234032.241215-1-tony.luck@xxxxxxxxx/
>
> Any switches in existing code would need to have a "default:" case
Boo. I much prefer the no-default case as it forces someone adding a new enum entry
to inspect every switch statement. But I'll change it.
> added because the new events are in the same "enum" but totally
> unrelated to the existing events. Other code changes in that series
> deleted many of the switches anyway.
Cool!
> Patch 23 in that series changes QOS_NUM_EVENTS from a #define
> to the last element in the enum without any issues.
I'll do that here and add the defaults in this patch to reduce conflicts.
Thanks,
James