On Tue, Aug 09, 2016 at 02:05:43PM -0400, Steven Rostedt wrote:

+int arch_smi_count(void)
+{
+	unsigned long long count;
+	int err;
+
+	err = rdmsrl_safe(MSR_SMI_COUNT, &count);
+	if (err)
+		return 0;

That's really yucky, relying on _safe() to detect availability.

Also, I just found AMD Fam15h has this counter through PMCs (event
0x2b).

+
+	return count;
+}