Re: perf script: Question: Python trace processing script contains the tid of the process in the common_pid attribute

From: Arun Kalyanasundaram
Date: Wed Jul 05 2017 - 12:22:14 EST

Hi Arnaldo,

Thank you for your reply.
I actually meant tracepoint event handlers: def
trace_unhandled(event_name, context, event_fields_dict)
The dict parameter contains an attribute "common_pid" which is
actually the "tid" of the thread. There are no other attributes that
contain the actual pid of the process. So, I was wondering if this is
something intentional? If not I can share a patch to fix this.

- Arun

On Sat, Jul 1, 2017 at 7:47 AM, Arnaldo Carvalho de Melo
<acme@xxxxxxxxxx> wrote:
> Em Fri, Jun 30, 2017 at 03:40:57PM -0700, Arun Kalyanasundaram escreveu:
>> The handlers in the python script generated from "perf script" have an
>> attribute: common_pid. This attribute contains the tid of the process
>> instead of its pid. I would like to know if this is the expected behavior.
>> There are no other attributes in the Python handler that provide the pid
>> and knowing the process id is useful to be able to group all samples that
>> belong to the same process that generated different threads.
> Humm, you have:
> def process_event(param_dict):
> event_attr = param_dict["attr"]
> sample = param_dict["sample"]
> raw_buf = param_dict["raw_buf"]
> comm = param_dict["comm"]
> name = param_dict["ev_name"]
> And then, on sample you have (from a recent python script for processing
> Intel PT samples):
> def print_common_start(comm, sample, name):
> ts = sample["time"]
> cpu = sample["cpu"]
> pid = sample["pid"]
> tid = sample["tid"]
> print "%16s %5u/%-5u [%03u] %9u.%09u %7s:" % (comm, pid, tid, cpu, ts / 1000000000, ts %1000000000, name),
> - Arnaldo