linux/tools/perf/scripts/python/futex-contention.py
Joseph Schuchart 0f5f5bcd11 perf script: Add callchain to generic and tracepoint events
This provides valuable information for tracing performance problems.

Since this change alters the interface for the python scripts, also
adjust the script generation and the provided scripts.

Signed-off-by: Joseph Schuchart <joseph.schuchart@tu-dresden.de>
Acked-by: Thomas Ilsche <thomas.ilsche@tu-dresden.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Ilsche <thomas.ilsche@tu-dresden.de>
Link: http://lkml.kernel.org/r/53BE7E1B.10503@tu-dresden.de
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2014-07-16 17:57:33 -03:00

51 lines
1.5 KiB
Python

# futex contention
# (c) 2010, Arnaldo Carvalho de Melo <acme@redhat.com>
# Licensed under the terms of the GNU GPL License version 2
#
# Translation of:
#
# http://sourceware.org/systemtap/wiki/WSFutexContention
#
# to perf python scripting.
#
# Measures futex contention
import os, sys
sys.path.append(os.environ['PERF_EXEC_PATH'] + '/scripts/python/Perf-Trace-Util/lib/Perf/Trace')
from Util import *
process_names = {}
thread_thislock = {}
thread_blocktime = {}
lock_waits = {} # long-lived stats on (tid,lock) blockage elapsed time
process_names = {} # long-lived pid-to-execname mapping
def syscalls__sys_enter_futex(event, ctxt, cpu, s, ns, tid, comm, callchain,
nr, uaddr, op, val, utime, uaddr2, val3):
cmd = op & FUTEX_CMD_MASK
if cmd != FUTEX_WAIT:
return # we don't care about originators of WAKE events
process_names[tid] = comm
thread_thislock[tid] = uaddr
thread_blocktime[tid] = nsecs(s, ns)
def syscalls__sys_exit_futex(event, ctxt, cpu, s, ns, tid, comm, callchain,
nr, ret):
if thread_blocktime.has_key(tid):
elapsed = nsecs(s, ns) - thread_blocktime[tid]
add_stats(lock_waits, (tid, thread_thislock[tid]), elapsed)
del thread_blocktime[tid]
del thread_thislock[tid]
def trace_begin():
print "Press control+C to stop and show the summary"
def trace_end():
for (tid, lock) in lock_waits:
min, max, avg, count = lock_waits[tid, lock]
print "%s[%d] lock %x contended %d times, %d avg ns" % \
(process_names[tid], tid, lock, count, avg)