diff options
-rw-r--r-- | arch/x86/kernel/cpu/perf_counter.c | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/arch/x86/kernel/cpu/perf_counter.c b/arch/x86/kernel/cpu/perf_counter.c index 3776b0b630c..f9cd0849bd4 100644 --- a/arch/x86/kernel/cpu/perf_counter.c +++ b/arch/x86/kernel/cpu/perf_counter.c @@ -984,8 +984,15 @@ static int __hw_perf_counter_init(struct perf_counter *counter) * Branch tracing: */ if ((attr->config == PERF_COUNT_HW_BRANCH_INSTRUCTIONS) && - (hwc->sample_period == 1) && !bts_available()) - return -EOPNOTSUPP; + (hwc->sample_period == 1)) { + /* BTS is not supported by this architecture. */ + if (!bts_available()) + return -EOPNOTSUPP; + + /* BTS is currently only allowed for user-mode. */ + if (hwc->config & ARCH_PERFMON_EVENTSEL_OS) + return -EOPNOTSUPP; + } hwc->config |= config; |