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<P><SPAN LANG="en-gb"><FONT FACE="Times New Roman">Hi,</FONT></SPAN>
<BR><SPAN LANG="en-gb"><FONT FACE="Times New Roman">I have a big problem with fast lock mutex on arm CPU: </FONT></SPAN>
<BR><SPAN LANG="en-gb"><FONT FACE="Times New Roman">sometimes I find one or more children that go in an infinite loop, in the while loop of get_lock function. </FONT></SPAN>
<BR><SPAN LANG="en-gb"><FONT FACE="Times New Roman">They remain in Run for long time (sometimes hours) and openser keeps 100% CPU.</FONT></SPAN>
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<P><SPAN LANG="en-gb"><FONT FACE="Times New Roman">Now I have changed the functions get_lock and tsl in order to obtain more info and </FONT></SPAN>
<BR><SPAN LANG="en-gb"><FONT FACE="Times New Roman">I observe that (if and) when the process finish the cycle, it have done a big amount of cycles. </FONT></SPAN>
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<P><SPAN LANG="en-gb"><FONT FACE="Times New Roman">This the log with my added info:</FONT></SPAN>
<BR><SPAN LANG="en-gb"><FONT FACE="Times New Roman">Mar 26 20:29:08 SAM-IP openser[1645]: NOTICE:tm:_lock: ret 1 (cycle)</FONT></SPAN>
<BR><SPAN LANG="en-gb"><FONT FACE="Times New Roman">Mar 26 20:29:51 SAM-IP openser[1645]: NOTICE:tm:_lock: ret 1 (cycle)</FONT></SPAN>
<BR><SPAN LANG="en-gb"><FONT FACE="Times New Roman">Mar 26 20:29:55 SAM-IP openser[1645]: NOTICE:tm:_lock: ret 1 (cycle)</FONT></SPAN>
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<P><SPAN LANG="en-gb"><FONT FACE="Times New Roman">Mar 26 20:29:55 SAM-IP openser[1645]: NOTICE:tm:t_retransmit_reply: MYTM lock </FONT></SPAN>
<BR><SPAN LANG="en-gb"><FONT FACE="Times New Roman">[process in loop]</FONT></SPAN>
<BR><SPAN LANG="en-gb"><FONT FACE="Times New Roman">Mar 26 20:33:46 SAM-IP openser[1645]: NOTICE:tm:_lock: ret 59374917 (cycle)</FONT></SPAN>
<BR><SPAN LANG="en-gb"><FONT FACE="Times New Roman">[after 4 minutes and 59374917 cycles, this is an example with a "short" loop]</FONT></SPAN>
<BR><SPAN LANG="en-gb"><FONT FACE="Times New Roman">Mar 26 20:33:46 SAM-IP openser[1645]: NOTICE:tm:t_retransmit_reply: MYTM lock done </FONT></SPAN>
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<P><SPAN LANG="en-gb"><FONT FACE="Times New Roman">I’m not able to recognize the call flow that generates the loop (I know only that it always happens when t_retransmit_reply calls LOCK_REPLIES), </FONT></SPAN></P>
<P><SPAN LANG="en-gb"><FONT FACE="Times New Roman">but I urgently need a work around to escape from the loop.</FONT></SPAN>
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<P><SPAN LANG="en-gb"><FONT FACE="Times New Roman">This is the get_lock function with my counter j:</FONT></SPAN>
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<P><SPAN LANG="en-gb"><FONT FACE="Times New Roman">inline static int get_lock(fl_lock_t* lock)</FONT></SPAN>
<BR><SPAN LANG="en-gb"><FONT FACE="Times New Roman">{</FONT></SPAN>
<BR><SPAN LANG="en-gb"><FONT FACE="Times New Roman">#ifdef ADAPTIVE_WAIT</FONT></SPAN>
<BR><SPAN LANG="en-gb"> <FONT FACE="Times New Roman">int i=ADAPTIVE_WAIT_LOOPS;</FONT></SPAN>
<BR><SPAN LANG="en-gb"> <FONT FACE="Times New Roman">int j=1; /***** my change ****/</FONT></SPAN>
<BR><SPAN LANG="en-gb"><FONT FACE="Times New Roman">#endif</FONT></SPAN>
<BR><SPAN LANG="en-gb"> </SPAN>
<BR><SPAN LANG="en-gb"> <FONT FACE="Times New Roman">while(tsl(lock)){</FONT></SPAN>
<BR><SPAN LANG="en-gb"><FONT FACE="Times New Roman">#ifdef BUSY_WAIT</FONT></SPAN>
<BR><SPAN LANG="en-gb"><FONT FACE="Times New Roman">#elif defined ADAPTIVE_WAIT</FONT></SPAN>
<BR><SPAN LANG="en-gb"> <FONT FACE="Times New Roman">j++; /***** my change ****/</FONT></SPAN>
<BR><SPAN LANG="en-gb"> <FONT FACE="Times New Roman">if (i>0) i--;</FONT></SPAN>
<BR><SPAN LANG="en-gb"> <FONT FACE="Times New Roman">else sched_yield();</FONT></SPAN>
<BR><SPAN LANG="en-gb"><FONT FACE="Times New Roman">#else</FONT></SPAN>
<BR><SPAN LANG="en-gb"> <FONT FACE="Times New Roman">sched_yield();</FONT></SPAN>
<BR><SPAN LANG="en-gb"><FONT FACE="Times New Roman">#endif</FONT></SPAN>
<BR><SPAN LANG="en-gb"> <FONT FACE="Times New Roman">}</FONT></SPAN>
<BR><SPAN LANG="en-gb"> <FONT FACE="Times New Roman">return(j);</FONT></SPAN>
<BR><SPAN LANG="en-gb"><FONT FACE="Times New Roman">}</FONT></SPAN>
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<P><SPAN LANG="en-gb"><FONT FACE="Times New Roman">Can I break the lock when my counter reaches a big value? </FONT></SPAN>
<BR><SPAN LANG="en-gb"><FONT FACE="Times New Roman">Should I call the unlock function after the break?</FONT></SPAN>
<BR><SPAN LANG="en-gb"><FONT FACE="Times New Roman">which value can be considered too big?</FONT></SPAN>
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<P><SPAN LANG="en-gb"><FONT FACE="Times New Roman">Thanks,</FONT></SPAN>
<BR><SPAN LANG="en-gb"><FONT FACE="Times New Roman">Daniele </FONT></SPAN>
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