perf, x86: Fixup the precise_ip computation

In case we don't have PEBS, the LBR fixup doesn't make sense.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Stephane Eranian <eranian@google.com>
LKML-Reference: <20101019134808.354429461@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 5 insertions, 4 deletions

diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c
index fe73c1844a9a..f369c53315a5 100644
--- a/arch/x86/kernel/cpu/perf_event.c
+++ b/arch/x86/kernel/cpu/perf_event.c
@@ -497,12 +497,13 @@ static int x86_pmu_hw_config(struct perf_event *event)
                 int precise = 0;
 
                 /* Support for constant skid */
-                if (x86_pmu.pebs)
+                if (x86_pmu.pebs) {
                         precise++;
 
-                /* Support for IP fixup */
-                if (x86_pmu.lbr_nr)
-                        precise++;
+                        /* Support for IP fixup */
+                        if (x86_pmu.lbr_nr)
+                                precise++;
+                }
 
                 if (event->attr.precise_ip > precise)
                         return -EOPNOTSUPP;