perf/powerpc: reset event hw state when adding it to the PMU

When adding an event to the PMU with PERF_EF_START the STOPPED and UPTODATE
flags need to be cleared in the hw.event status variable because they are
preventing the update of the event count on overflow interrupt.

Signed-off-by: Alexandru-Cezar Sardan <alexandru.sardan@freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>

1 files changed, 3 insertions, 1 deletions

diff --git a/arch/powerpc/perf/core-fsl-emb.c b/arch/powerpc/perf/core-fsl-emb.c
index e9fe904b6538..5d747b4cb8ee 100644
--- a/arch/powerpc/perf/core-fsl-emb.c
+++ b/arch/powerpc/perf/core-fsl-emb.c
@@ -330,9 +330,11 @@ static int fsl_emb_pmu_add(struct perf_event *event, int flags)
         }
         local64_set(&event->hw.prev_count, val);
 
-        if (!(flags & PERF_EF_START)) {
+        if (unlikely(!(flags & PERF_EF_START))) {
                 event->hw.state = PERF_HES_STOPPED | PERF_HES_UPTODATE;
                 val = 0;
+        } else {
+                event->hw.state &= ~(PERF_HES_STOPPED | PERF_HES_UPTODATE);
         }
 
         write_pmc(i, val);