Date: Wed, 10 Jan 2007 13:44:06 -0500 From: Randall Stewart <rrs@cisco.com> To: current@freebsd.org Subject: how to find out what the other CPU is doing Message-ID: <45A533F6.7030405@cisco.com>
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All: I have now pinpointed a problem.. or at least I know whats going on.. I have a dual-core machine.. CPU1 gets swi: net running on it.. I am sure it has received an SCTP packet since it has a lock on a TCB. the sw4: clock sio in fact gets hung up waiting for the locked TCB that swi:net holds. The other CPU, cpu0 is still free.. I can thus drop into DDB> I took a core of this.. but I could not gain much.. and it comes from my ignorance I think.. So my question is how do I find out what loop swi:net is trapped in.. If I have a kernel core, can I somehow look at this? I dumped the entire stack and poked around in it a bit.. looking at where its esp and ebp were set.. but I could not figure out how to follow this.. I tried using proc 'tid' (as John suggested to me) and when I try a bt it just gives me a ???? and an address.. Is there anyway I can get a hint out of the situation. If I do trace in DDB> it just showed me where I was on CPU0 with the keyboard interupt.. etc.. Any help in getting additional info would be wonderful... I need to at least get a hint as to how this thing is in a loop.. I currently have the machine cooking again.. it takes 3-4 days to get it to hit this state... So if someone has an idea of something to try I would apprecicate it :-) Thanks in advance R -- Randall Stewart NSSTG - Cisco Systems Inc. 803-345-0369 <or> 803-317-4952 (cell)
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