Debugging deadlocks using SV semaphores via PROC FS

[Steffen Rumler]

Hi,

I have extended the PROC FS entry in ipc/sem.c for the 2.4.20 DEVEL
in order to debug deadlock problems; see attachment.

For each semaphore array, now also all array elements: (last-pid, sem.-value)
will be traced.

In this way, I can easy answer the question:

     "Which process is holding a distinct semaphore in a permanent way ?"

An subsequent strace of the found process provides additional information.



Steffen

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Steffen Rumler
ICN CP D NT SW 3
Siemens AG
Hofmannstr. 51                 Email: Steffen.Rumler at siemens.com
D-81359 Munich                 Phone: +49 89 722-44061
Germany                        Fax  : +49 89 722-36703

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