<div dir="ltr"><div dir="ltr"><div><div dir="ltr" class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div dir="ltr"><div>Thank you Genevieve, "cpu" field works. </div><div><br></div><div>Yonghong</div></div></div></div></div><br></div><br><div class="gmail_quote"><div dir="ltr">On Mon, Jan 21, 2019 at 7:57 PM Genevieve Bastien <<a href="mailto:gbastien@versatic.net">gbastien@versatic.net</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
  
    
  
  <div bgcolor="#FFFFFF">
    <p>Hi Yonghong,</p>
    <p>With TraceCompass XML analyses, you can use as state value or
      attribute an eventField called 'cpu' to get the CPU id of an
      event. For example,<br>
    </p>
    <p><stateAttribute type="eventField" value="cpu" /></p>
    <p>With LTTng traces, it will automatically be the CPU, obtained as
      Mathieu described, no need for an extra field.<br>
    </p>
    <p>Regards,</p>
    <p>Geneviève<br>
    </p>
    <p><br>
    </p>
    <div class="gmail-m_1715309599997022837moz-cite-prefix">On 2019-01-21 4:21 p.m., Yonghong Yan
      wrote:<br>
    </div>
    <blockquote type="cite">
      
      <div dir="ltr">Thank you. make sense. I am using Trace Compass XML
        based approach to display UST trace records. Using CPU id helps
        me easier to sort out the event records in trace compass. I will
        check out more on trace compass. 
        <div><br>
        </div>
        <div>Yonghong<br>
          <br>
        </div>
      </div>
      <br>
      <div class="gmail_quote">
        <div dir="ltr">On Mon, Jan 21, 2019 at 2:06 PM Mathieu Desnoyers
          <<a href="mailto:mathieu.desnoyers@efficios.com" target="_blank">mathieu.desnoyers@efficios.com</a>>
          wrote:<br>
        </div>
        <blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
          <div>
            <div style="font-family:arial,helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)">
              <div><br>
              </div>
              <div><span id="gmail-m_1715309599997022837gmail-m_-6511454066164686156zwchr">----- On
                  Jan 21, 2019, at 12:14 PM, Yonghong Yan <<a href="mailto:yanyh15@gmail.com" target="_blank">yanyh15@gmail.com</a>>
                  wrote:<br>
                </span></div>
              <div>
                <blockquote style="border-left:2px solid rgb(16,16,255);margin-left:5px;padding-left:5px;color:rgb(0,0,0);font-weight:normal;font-style:normal;text-decoration:none;font-family:Helvetica,Arial,sans-serif;font-size:12pt">
                  <div dir="ltr">
                    <div dir="ltr">I saw there is cpu_id field in
                      babeltrace list, how can I add it to the context
                      of UST tracepoint events. lttng add-context --list
                      does not show that field and I do not see a
                      similar field for the cpu_id. </div>
                  </div>
                </blockquote>
                <div><br>
                </div>
                <div>The cpu_id context only exists for the purpose of
                  lttng-ust and lttng-modules filtering.<br>
                </div>
                <div>(e.g. lttng enable-event {-u,-k} --filter
                  '$ctx.cpu_id == 2').<br>
                </div>
                <div><br>
                </div>
                <div>It is not possible to add it as context to the
                  streams, because its information would<br>
                </div>
                <div>be completely redundant with the fact that all the
                  data is written into per-cpu buffers,</div>
                <div>and the cpu_id field is available within each
                  packet context (which is right after each</div>
                <div>packet header).<br>
                </div>
                <div><br>
                </div>
                <div>You just need to use babeltrace to convert to text,
                  and while doing so, it prints a<br>
                </div>
                <div>"cpu_id = N" context based on the packet_context
                  cpu_id field for each event.<br>
                </div>
                <div><br>
                </div>
                <div>Thanks,</div>
                <div><br>
                </div>
                <div>Mathieu<br>
                </div>
              </div>
              <div><br>
              </div>
              <div>-- <br>
              </div>
              <div>Mathieu Desnoyers<br>
                EfficiOS Inc.<br>
                <a href="http://www.efficios.com" target="_blank">http://www.efficios.com</a></div>
            </div>
          </div>
        </blockquote>
      </div>
      <br>
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