perf top: Don't process samples with no valid machine object

The perf sample processing code relies on a valid machine object. Make
sure that this path is only entered when such a object exists.

A counter for samples where no machine object exits is also introduced
to give the user a message about these samples.

Reported-by: David Ahern <dsahern@gmail.com>
Reported-by: Jason Wang <jasowang@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1328893505-4115-2-git-send-email-joerg.roedel@amd.com
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index 94d55cb2048c..5a88c0dadf15 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -677,6 +677,12 @@ static void perf_event__process_sample(struct perf_tool *tool,
                 return;
         }
 
+        if (!machine) {
+                pr_err("%u unprocessable samples recorded.",
+                       top->session->hists.stats.nr_unprocessable_samples++);
+                return;
+        }
+
         if (event->header.misc & PERF_RECORD_MISC_EXACT_IP)
                 top->exact_samples++;