To show how to open tracepoint and access its fields.

Reported-and-tested-by: Jiri Pirko <j...@mellanox.com>
Link: http://lkml.kernel.org/n/tip-7xt9nvyl45qwbg9237f46...@git.kernel.org
Signed-off-by: Jiri Olsa <jo...@kernel.org>
---
 tools/perf/python/tracepoint.py | 47 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 47 insertions(+)
 create mode 100755 tools/perf/python/tracepoint.py

diff --git a/tools/perf/python/tracepoint.py b/tools/perf/python/tracepoint.py
new file mode 100755
index 000000000000..eb4dbed57de7
--- /dev/null
+++ b/tools/perf/python/tracepoint.py
@@ -0,0 +1,47 @@
+#! /usr/bin/python
+# -*- python -*-
+# -*- coding: utf-8 -*-
+
+import perf
+
+class tracepoint(perf.evsel):
+    def __init__(self, sys, name):
+        config = perf.tracepoint(sys, name)
+        perf.evsel.__init__(self,
+                            type   = perf.TYPE_TRACEPOINT,
+                            config = config,
+                            freq = 0, sample_period = 1, wakeup_events = 1,
+                            sample_type = perf.SAMPLE_PERIOD | perf.SAMPLE_TID 
| perf.SAMPLE_CPU | perf.SAMPLE_RAW | perf.SAMPLE_TIME)
+
+def main():
+    tp      = tracepoint("sched", "sched_switch")
+    cpus    = perf.cpu_map()
+    threads = perf.thread_map(-1)
+
+    evlist = perf.evlist(cpus, threads)
+    evlist.add(tp)
+    evlist.open()
+    evlist.mmap()
+
+    while True:
+        evlist.poll(timeout = -1)
+        for cpu in cpus:
+            event = evlist.read_on_cpu(cpu)
+            if not event:
+                continue
+
+            if not isinstance(event, perf.sample_event):
+                continue
+
+            print "time %u prev_comm=%s prev_pid=%d prev_prio=%d 
prev_state=0x%x ==> next_comm=%s next_pid=%d next_prio=%d" % (
+                   event.sample_time,
+                   event.prev_comm,
+                   event.prev_pid,
+                   event.prev_prio,
+                   event.prev_state,
+                   event.next_comm,
+                   event.next_pid,
+                   event.next_prio)
+
+if __name__ == '__main__':
+    main()
-- 
2.4.11

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