+ clock_freq = extract_clock(l, cpu, 0);
+
+ if (unlikely(clock_freq == 0)) {
+ /*
+ * On some CPUs, we can see transient MSR values (which are
+ * not present in _PSS), while CPU is doing some automatic
+ * P-state transition (like TM2). Get the last freq set
+ * in PERF_CTL.
+ */
+ rdmsr(MSR_IA32_PERF_CTL, l, h);
+ clock_freq = extract_clock(l, cpu, 1);
+ }
+