Re: [PATCH v4 15/21] x86/resctrl: Abstract __rmid_read()

From: Reinette Chatre
Date: Tue May 17 2022 - 17:23:38 EST


Hi James,

On 4/12/2022 5:44 AM, James Morse wrote:

> @@ -180,14 +180,24 @@ static u64 __rmid_read(u32 rmid, enum resctrl_event_id eventid)
> * are error bits.
> */
> wrmsr(MSR_IA32_QM_EVTSEL, eventid, rmid);
> - rdmsrl(MSR_IA32_QM_CTR, val);
> + rdmsrl(MSR_IA32_QM_CTR, msr_val);
>
> - return val;
> + if (msr_val & RMID_VAL_ERROR)
> + return -EIO;
> + if (msr_val & RMID_VAL_UNAVAIL)
> + return -EINVAL;
> +
> + *val = msr_val;
> +
> + return 0;
> }
>

In above EIO is used to represent RMID_VAL_ERROR ...

> @@ -343,7 +355,7 @@ static u64 __mon_event_count(u32 rmid, struct rmid_read *rr)
> * Code would never reach here because an invalid
> * event id would fail the __rmid_read.
> */
> - return RMID_VAL_ERROR;
> + return -EINVAL;
> }
>
> if (rr->first) {

I understand it can be seen as a symbolic change but could
RMID_VAL_ERROR consistently be associated with the same error?

Reinette