Re: [PATCH 2/5] x86/mbm: Intel Memory B/W Monitoring enumeration and init

[Vikas Shivappa]

On Wed, 24 Feb 2016, Thomas Gleixner wrote:

On Wed, 10 Feb 2016, Vikas Shivappa wrote:ar

+static int intel_mbm_init(void)
+{
+       int ret = 0, array_size, maxid = cqm_max_rmid + 1;
+
+       mbm_socket_max = cpumask_weight(&cqm_cpumask);

This should use the new topology_max_packages() function, so you can alloc
your array correctly even if not all sockets are online/plugged yet.

Will fix. Thanks for pointing out.

+       array_size = sizeof(struct sample) * maxid * mbm_socket_max;
+       mbm_local = kmalloc(array_size, GFP_KERNEL);
+       if (!mbm_local) {
+               ret = -ENOMEM;

return -ENOMEM is sufficient here.

Will fix

+               goto out;
+       }
+
+       mbm_total = kmalloc(array_size, GFP_KERNEL);
+       if (!mbm_total) {
+               kfree(mbm_local);
+               ret = -ENOMEM;
+       }
+out:
+
+       return ret;
+}
+
        cqm_l3_scale = boot_cpu_data.x86_cache_occ_scale;
@@ -1384,14 +1520,34 @@ static int __init intel_cqm_init(void)

        __perf_cpu_notifier(intel_cqm_cpu_notifier);

You really should register the notifier _AFTER_ registering the pmu. That
needs to be fixed anyway, because the existing code leaks the notifier AND
memory in case perf_pmu_register fails.

Correct, Will fix the notifier leak

Thanks,
Vikas

Thanks,

        tglx