1 files changed, 5 insertions, 5 deletions

diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index 126a302c481c..999835b6112b 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -1901,11 +1901,12 @@ static void __perf_event_read(void *info)
                 return;
 
         raw_spin_lock(&ctx->lock);
-        update_context_time(ctx);
+        if (ctx->is_active)
+                update_context_time(ctx);
         update_event_times(event);
+        if (event->state == PERF_EVENT_STATE_ACTIVE)
+                event->pmu->read(event);
         raw_spin_unlock(&ctx->lock);
-
-        event->pmu->read(event);
 }
 
 static inline u64 perf_event_count(struct perf_event *event)
@@ -1999,8 +2000,7 @@ static int alloc_callchain_buffers(void)
          * accessed from NMI. Use a temporary manual per cpu allocation
          * until that gets sorted out.
          */
-        size = sizeof(*entries) + sizeof(struct perf_callchain_entry *) *
-                num_possible_cpus();
+        size = offsetof(struct callchain_cpus_entries, cpu_entries[nr_cpu_ids]);
 
         entries = kzalloc(size, GFP_KERNEL);
         if (!entries)