Re: [PATCH 1/9] x86/intel_rdt: Fix MBA parsing callback

From: Thomas Gleixner
Date: Sat Sep 15 2018 - 06:14:10 EST


On Fri, 14 Sep 2018, Fenghua Yu wrote:
> int parse_cbm(void *_data, struct rdt_resource *r, struct rdt_domain *d);
> -int parse_bw(void *_buf, struct rdt_resource *r, struct rdt_domain *d);
> +int parse_bw(void *_data, struct rdt_resource *r, struct rdt_domain *d);

Sorry no. This keeps the code equally error prone as it was. Why is that
argument a void pointer in the first place?

> extern struct mutex rdtgroup_mutex;
>
> diff --git a/arch/x86/kernel/cpu/intel_rdt_ctrlmondata.c b/arch/x86/kernel/cpu/intel_rdt_ctrlmondata.c
> index af358ca05160..d427c86e7cd0 100644
> --- a/arch/x86/kernel/cpu/intel_rdt_ctrlmondata.c
> +++ b/arch/x86/kernel/cpu/intel_rdt_ctrlmondata.c
> @@ -28,6 +28,11 @@
> #include <linux/slab.h>
> #include "intel_rdt.h"
>
> +struct rdt_parse_data {
> + struct rdtgroup *rdtgrp;
> + char *buf;
> +};

This is a copy of rdt_cbm_parse_data. Sigh.

The right thing to do here is

1) rename struct rdt_cbm_parse_data to struct rdt_parse_data

2) Move it to a header file

3) Change the argument of parse_ctrlval from void * to struct
rdt_parse_data *

Everything else is just proliferating the initial underlying problem of
having a void pointer in those callbacks for no reason at all.

Thanks,

tglx