xref: /linux/tools/perf/python/tracepoint.py (revision e58e871becec2d3b04ed91c0c16fe8deac9c9dfa)
1#! /usr/bin/python
2# -*- python -*-
3# -*- coding: utf-8 -*-
4
5import perf
6
7class tracepoint(perf.evsel):
8    def __init__(self, sys, name):
9        config = perf.tracepoint(sys, name)
10        perf.evsel.__init__(self,
11                            type   = perf.TYPE_TRACEPOINT,
12                            config = config,
13                            freq = 0, sample_period = 1, wakeup_events = 1,
14                            sample_type = perf.SAMPLE_PERIOD | perf.SAMPLE_TID | perf.SAMPLE_CPU | perf.SAMPLE_RAW | perf.SAMPLE_TIME)
15
16def main():
17    tp      = tracepoint("sched", "sched_switch")
18    cpus    = perf.cpu_map()
19    threads = perf.thread_map(-1)
20
21    evlist = perf.evlist(cpus, threads)
22    evlist.add(tp)
23    evlist.open()
24    evlist.mmap()
25
26    while True:
27        evlist.poll(timeout = -1)
28        for cpu in cpus:
29            event = evlist.read_on_cpu(cpu)
30            if not event:
31                continue
32
33            if not isinstance(event, perf.sample_event):
34                continue
35
36            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" % (
37                   event.sample_time,
38                   event.prev_comm,
39                   event.prev_pid,
40                   event.prev_prio,
41                   event.prev_state,
42                   event.next_comm,
43                   event.next_pid,
44                   event.next_prio)
45
46if __name__ == '__main__':
47    main()
48