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<p class="MsoNormal">Hi There,</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">we are working with etherlab's ethercat master and recently we've encountered a problem that is related to a non interruptible wait_event().</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The scenario:</p>
<p class="MsoNormal">A multi-threaded user space app cyclically reads SDO from some ecat slave.</p>
<p class="MsoNormal">The user space app then crashes.</p>
<p class="MsoNormal">All the threads end besides the one that performs the SDO read:</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">.....</p>
<p class="MsoNormal">1022 1022 TS - 0 19 0 0.0 Zl task_dead abcde <defunct></p>
<p class="MsoNormal">1022 1202 RR 2 - 42 0 0.6 Dl ecrt_master_sdo_upload abcde1</p>
<p class="MsoNormal">.....</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">This situation interferes with debugging the app, and prevents a core dump from being generated.</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">In master.c in ecrt_master_sdo_upload() I see an invoke of wait_event_interruptible() followed by an invoke of wait_event().</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">After changing wait_event() to wait_event_interruptible() the app can successfully crash, and it is now easier to debug.</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Needless to say, we need a core dump to be generated when the app crashes at costumer's site.</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The question is what is the reason behind using wait_event() instead of wait_event_interruptible() ?</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Is it safe for us to change the code?</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks,</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Nir.<o:p></o:p></p>
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