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