perf/x86: Dump DEBUGCTL in PMU dump

LBRs and LBR freezing are controlled through the DEBUGCTL MSR. So
dump the state of DEBUGCTL too when dumping the PMU state.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: eranian@google.com
Link: http://lkml.kernel.org/r/1425059312-18217-3-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

arch/x86/kernel/cpu/perf_event.c

@@ -1171,7 +1171,7 @@ static void x86_pmu_start(struct perf_event *event, int flags)
 void perf_event_print_debug(void)
 {
 	u64 ctrl, status, overflow, pmc_ctrl, pmc_count, prev_left, fixed;
-	u64 pebs;
+	u64 pebs, debugctl;
 	struct cpu_hw_events *cpuc;
 	unsigned long flags;
 	int cpu, idx;
@@ -1197,6 +1197,10 @@ void perf_event_print_debug(void)
 		pr_info("CPU#%d: overflow:   %016llx\n", cpu, overflow);
 		pr_info("CPU#%d: fixed:      %016llx\n", cpu, fixed);
 		pr_info("CPU#%d: pebs:       %016llx\n", cpu, pebs);
+		if (x86_pmu.lbr_nr) {
+			rdmsrl(MSR_IA32_DEBUGCTLMSR, debugctl);
+			pr_info("CPU#%d: debugctl:   %016llx\n", cpu, debugctl);
+		}
 	}
 	pr_info("CPU#%d: active:     %016llx\n", cpu, *(u64 *)cpuc->active_mask);