Re: [PATCH 5/8] x86/intel_rct/mba: Add MBA structures and initialize MBA

[Shivappa Vikas]

On Mon, 16 Jan 2017, Thomas Gleixner wrote:

> On Tue, 10 Jan 2017, Vikas Shivappa wrote:
> > +static void rdt_get_mem_config(struct rdt_resource *r)
> > +{
> > +	union cpuid_0x10_3_eax eax;
> > +	union cpuid_0x10_x_edx edx;
> > +	u32 ebx, ecx;
> > +
> > +	cpuid_count(0x00000010, 3, &eax.full, &ebx, &ecx, &edx.full);
> > +	r->num_closid = edx.split.cos_max + 1;
> > +	r->max_delay = eax.split.max_delay + 1;
> > +	r->no_ctrl = 0;
> > +	if (ecx & MBE_IS_LINEAR)
> > +		r->delay_linear = true;
> > +
> > +	if (r->delay_linear)
> > +		r->delay_gran = MAX_MBA_THRTL - r->max_delay;
>
> What's the point of this extra conditional?
>
> 	if (ecx & MBE_IS_LINEAR) {
> 		r->delay_linear = true;
> 		r->delay_gran = MAX_MBA_THRTL - r->max_delay;
> 	}
>
> would be too obvious and easy to understand, right?

Will fix.

> > +static int domain_setup_ctrlval(struct rdt_resource *r, struct rdt_domain *d)
> > +{
> > +	int i;
> > +
> > +	d->ctrl_val = kmalloc_array(r->num_closid,
> > +				     sizeof(*d->ctrl_val), GFP_KERNEL);
> > +	if (!d->ctrl_val) {
> > +		kfree(d);
>
> Freeing memory in the error path of some other random function is just wrong.
>
> 	if (!d->ctrl_val)
> 		return -ENOMEM;
>
> and deal with the fallout at the calling function.

Will fix.. Thanks for pointing out.

Vikas

> Thanks,
>
> 	tglx