perf: Disable PERF_SAMPLE_BRANCH_* when not supported

PERF_SAMPLE_BRANCH_* is disabled for:

 - SW events (sw counters, tracepoints)
 - HW breakpoints
 - ALL but Intel x86 architecture
 - AMD64 processors

Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1328826068-11713-10-git-send-email-eranian@google.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 4 insertions, 0 deletions

diff --git a/arch/alpha/kernel/perf_event.c b/arch/alpha/kernel/perf_event.c
index 8143cd7cdbfb..0dae252f7a33 100644
--- a/arch/alpha/kernel/perf_event.c
+++ b/arch/alpha/kernel/perf_event.c
@@ -685,6 +685,10 @@ static int alpha_pmu_event_init(struct perf_event *event)
 {
         int err;
 
+        /* does not support taken branch sampling */
+        if (has_branch_stack(event))
+                return -EOPNOTSUPP;
+
         switch (event->attr.type) {
         case PERF_TYPE_RAW:
         case PERF_TYPE_HARDWARE: