xref: /OK3568_Linux_fs/kernel/tools/perf/scripts/python/futex-contention.py (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun# futex contention
2*4882a593Smuzhiyun# (c) 2010, Arnaldo Carvalho de Melo <acme@redhat.com>
3*4882a593Smuzhiyun# Licensed under the terms of the GNU GPL License version 2
4*4882a593Smuzhiyun#
5*4882a593Smuzhiyun# Translation of:
6*4882a593Smuzhiyun#
7*4882a593Smuzhiyun# http://sourceware.org/systemtap/wiki/WSFutexContention
8*4882a593Smuzhiyun#
9*4882a593Smuzhiyun# to perf python scripting.
10*4882a593Smuzhiyun#
11*4882a593Smuzhiyun# Measures futex contention
12*4882a593Smuzhiyun
13*4882a593Smuzhiyunfrom __future__ import print_function
14*4882a593Smuzhiyun
15*4882a593Smuzhiyunimport os
16*4882a593Smuzhiyunimport sys
17*4882a593Smuzhiyunsys.path.append(os.environ['PERF_EXEC_PATH'] +
18*4882a593Smuzhiyun                '/scripts/python/Perf-Trace-Util/lib/Perf/Trace')
19*4882a593Smuzhiyunfrom Util import *
20*4882a593Smuzhiyun
21*4882a593Smuzhiyunprocess_names = {}
22*4882a593Smuzhiyunthread_thislock = {}
23*4882a593Smuzhiyunthread_blocktime = {}
24*4882a593Smuzhiyun
25*4882a593Smuzhiyunlock_waits = {}  # long-lived stats on (tid,lock) blockage elapsed time
26*4882a593Smuzhiyunprocess_names = {}  # long-lived pid-to-execname mapping
27*4882a593Smuzhiyun
28*4882a593Smuzhiyun
29*4882a593Smuzhiyundef syscalls__sys_enter_futex(event, ctxt, cpu, s, ns, tid, comm, callchain,
30*4882a593Smuzhiyun                              nr, uaddr, op, val, utime, uaddr2, val3):
31*4882a593Smuzhiyun    cmd = op & FUTEX_CMD_MASK
32*4882a593Smuzhiyun    if cmd != FUTEX_WAIT:
33*4882a593Smuzhiyun        return  # we don't care about originators of WAKE events
34*4882a593Smuzhiyun
35*4882a593Smuzhiyun    process_names[tid] = comm
36*4882a593Smuzhiyun    thread_thislock[tid] = uaddr
37*4882a593Smuzhiyun    thread_blocktime[tid] = nsecs(s, ns)
38*4882a593Smuzhiyun
39*4882a593Smuzhiyun
40*4882a593Smuzhiyundef syscalls__sys_exit_futex(event, ctxt, cpu, s, ns, tid, comm, callchain,
41*4882a593Smuzhiyun                             nr, ret):
42*4882a593Smuzhiyun    if tid in thread_blocktime:
43*4882a593Smuzhiyun        elapsed = nsecs(s, ns) - thread_blocktime[tid]
44*4882a593Smuzhiyun        add_stats(lock_waits, (tid, thread_thislock[tid]), elapsed)
45*4882a593Smuzhiyun        del thread_blocktime[tid]
46*4882a593Smuzhiyun        del thread_thislock[tid]
47*4882a593Smuzhiyun
48*4882a593Smuzhiyun
49*4882a593Smuzhiyundef trace_begin():
50*4882a593Smuzhiyun    print("Press control+C to stop and show the summary")
51*4882a593Smuzhiyun
52*4882a593Smuzhiyun
53*4882a593Smuzhiyundef trace_end():
54*4882a593Smuzhiyun    for (tid, lock) in lock_waits:
55*4882a593Smuzhiyun        min, max, avg, count = lock_waits[tid, lock]
56*4882a593Smuzhiyun        print("%s[%d] lock %x contended %d times, %d avg ns [max: %d ns, min %d ns]" %
57*4882a593Smuzhiyun              (process_names[tid], tid, lock, count, avg, max, min))
58