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<p class="MsoNormal">Hi Team / Jerin,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I am trying to use DPDK Trace Library functionality in my DPDK application. I've successfully observed the trace files being generated by invoking
<code><b><span style="font-size:10.0pt;font-family:"Calibri",sans-serif">rte_trace_save()</span></b></code><b>,</b> particularly when utilizing the EAL option
<b>'--trace=.*'<o:p></o:p></b></p>
<p class="MsoNormal"><br>
I found following statement in the programmer guide,<br>
<br>
<o:p></o:p></p>
<p class="MsoNormal"><i><span style="color:#0070C0">The trace memory will be allocated through an internal function __rte_trace_mem_per_thread_alloc(). The trace memory will be allocated per thread to enable lock less trace-emit function.<o:p></o:p></span></i></p>
<p class="MsoNormal"><i><span style="color:#0070C0">For non lcore threads, the trace memory is allocated on the first trace emission.<o:p></o:p></span></i></p>
<p class="MsoNormal"><i><span style="color:#0070C0">For lcore threads, if trace points are enabled through a EAL option, the trace memory is allocated when the threads are known of DPDK (rte_eal_init for EAL lcores, rte_thread_register for non-EAL lcores).
Otherwise<b>, <span style="background:yellow;mso-highlight:yellow">when trace points are enabled later in the life of the application</span></b>, the behavior is the same as non lcore threads and the trace memory is allocated on the first trace emission.<o:p></o:p></span></i></p>
<p class="MsoNormal"><o:p></o:p></p>
<p class="MsoNormal">I attempted to enable trace points at runtime using the <b>'rte_trace_regexp("lib.mempool.*", true)</b>' API, though I'm unsure if this is the correct approach. While the call appears to succeed, I'm puzzled by the absence of any trace
files being generated even after invoking <b>rte_trace_save().</b><br>
<br>
When adding a new trace point in my application code as per the documentation, I used
<b>rte_trace_regexp("myapp.trace.test", true)</b> to enable it. However, I encountered a failure when attempting to look up the API.<o:p></o:p></p>
<p class="MsoNormal"><br>
Apr 22 09:53:07.486 [USDP] [DPDK] EAL: <b>rte_trace_regexp():207</b> NAG1:inside rte_trace_regexp<o:p></o:p></p>
<p class="MsoNormal">Apr 22 09:53:07.486 [USDP] [DPDK] EAL: <b>rte_trace_regexp():212</b> NAG2:inside rte_trace_regexp<o:p></o:p></p>
<p class="MsoNormal">Apr 22 09:53:07.486 [USDP] [DPDK] EAL: <b>rte_trace_regexp():231</b> NAG4:inside rte_trace_regexp<o:p></o:p></p>
<p class="MsoNormal">Apr 22 09:53:07.486 [USDP] ***NAG***: DPDK-TRACE:rte_trace_regexp failed<br>
<br>
<o:p></o:p></p>
<p class="MsoNormal">I have the following queries,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l0 level1 lfo1"><![if !supportLists]><span style="mso-list:Ignore">1.<span style="font:7.0pt "Times New Roman"">
</span></span><![endif]>How to enable/disable the trace files runtime in a dpdk application?<o:p></o:p></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l0 level1 lfo1"><![if !supportLists]><span style="mso-list:Ignore">2.<span style="font:7.0pt "Times New Roman"">
</span></span><![endif]>How to trigger new trace points added in the application code?<o:p></o:p></p>
<p class="MsoNormal"><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Regards,<br>
Nagendra<o:p></o:p></p>
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