linux-kernel - Re: RE: RE: [PATCH v8 19/25] x86/resctrl: Auto assign/unassign counters when mbm_cntr

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Message-ID: <a972dfe9-341b-416c-a245-0834583c6620@amd.com>
Date: Mon, 14 Oct 2024 11:35:27 -0500
From: "Moger, Babu" <babu.moger@....com>
To: "Luck, Tony" <tony.luck@...el.com>
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Subject: Re: RE: RE: [PATCH v8 19/25] x86/resctrl: Auto assign/unassign
 counters when mbm_cntr_assign is enabled



On 12/31/69 18:00, Luck, Tony wrote:
>>>>>> +  if (!ret && is_mbm_local_enabled())
>>>>>> +          ret = rdtgroup_assign_cntr_event(r, rdtgrp, NULL, QOS_L3_MBM_LOCAL_EVENT_ID);
>>>
>>> Now this call succeeds. The failure of the previous call is forgotten as "ret" is
>>> overwritten with the success code.
>>
>> It will not make this call if the first call fails because of this check.
>>
>>         if (!ret && is_mbm_local_enabled())
>>                 ret = rdtgroup_assign_cntr_event(r, rdtgrp, NULL,
>> QOS_L3_MBM_LOCAL_EVENT_ID);
>>
>>         return ret;
>>
>> Here if (!1) evaluates to false.
>>
>> Did I miss something?
> 
> You didn't.
> 
> I missed the check for ret in the local case.

That is fine,

> 
> It is still the case that callers don't care about the return value.

That is correct.

-- 
Thanks
Babu Moger