From: Namhyung Kim <namhyung....@lge.com>

perf_event_task_event() iterates pmu list and generate events for each
eligible pmu context.  But if task_event has task_ctx like in EXIT
it'll generate events even though the pmu doesn't have an eligible one.
Fix it by moving the code to proper places.

Before this patch:

  $ perf record -n true
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.006 MB perf.data (~248 samples) ]

  $ perf report -D | tail
  Aggregated stats:
             TOTAL events:         73
              MMAP events:         67
              COMM events:          2
              EXIT events:          4
  cycles stats:
             TOTAL events:         73
              MMAP events:         67
              COMM events:          2
              EXIT events:          4

After this patch:

  $ perf report -D | tail
  Aggregated stats:
             TOTAL events:         70
              MMAP events:         67
              COMM events:          2
              EXIT events:          1
  cycles stats:
             TOTAL events:         70
              MMAP events:         67
              COMM events:          2
              EXIT events:          1

Signed-off-by: Namhyung Kim <namhy...@kernel.org>
---
 kernel/events/core.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/kernel/events/core.c b/kernel/events/core.c
index 53ac21cc4012..73ea6fcacf52 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -4432,12 +4432,15 @@ static void perf_event_task_event(struct 
perf_task_event *task_event)
                        if (ctxn < 0)
                                goto next;
                        ctx = rcu_dereference(current->perf_event_ctxp[ctxn]);
+                       if (ctx)
+                               perf_event_task_ctx(ctx, task_event);
                }
-               if (ctx)
-                       perf_event_task_ctx(ctx, task_event);
 next:
                put_cpu_ptr(pmu->pmu_cpu_context);
        }
+       if (task_event->task_ctx)
+               perf_event_task_ctx(task_event->task_ctx, task_event);
+
        rcu_read_unlock();
 }
 
-- 
1.7.11.7

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