perf/x86: Only dump PEBS register when PEBS has been detected

Technically PEBS_ENABLED is only guaranteed to exist when we
detected PEBS. So add a check for this to the PMU dump function.
I don't think it can happen on a real CPU, but could in a VM.

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/1425059312-18217-4-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Andi Kleen 2015-02-27 09:48:32 -08:00 committed by Ingo Molnar
parent da3e606d88
commit 15fde1101a

View File

@ -1189,14 +1189,16 @@ void perf_event_print_debug(void)
rdmsrl(MSR_CORE_PERF_GLOBAL_STATUS, status);
rdmsrl(MSR_CORE_PERF_GLOBAL_OVF_CTRL, overflow);
rdmsrl(MSR_ARCH_PERFMON_FIXED_CTR_CTRL, fixed);
rdmsrl(MSR_IA32_PEBS_ENABLE, pebs);
pr_info("\n");
pr_info("CPU#%d: ctrl: %016llx\n", cpu, ctrl);
pr_info("CPU#%d: status: %016llx\n", cpu, status);
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.pebs_constraints) {
rdmsrl(MSR_IA32_PEBS_ENABLE, pebs);
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);