[Crash-utility] Add an option "-c" for commamd runq

[WeiJiangang]

Hi Dave，
	As you mentioned in last email, sometimes, we really need to compare

timestamps of runqueue objects with those of current task's task_struct
objects .
	The usecase where such feature is needed is the situation where
curcent
processes in crash dump is in the state with interrupt disabled. Then timer 
interrupts is also disabled, so there's clear difference between CPU's
timestamp
and current task's timestamp. The latter can be abtainned easily by using ps
-l.
But the field names of timestamp values in runqueue objects vary according
to
kernel versions, it's inconvenient and troublesome to get needed information
about runqueue's timestamp for users. That's why adding an option to runq
command.
	Any question please contact with me.

Regards,
Wei Jiangang

----- Original Message -----
> Hello Dave,
> 	The patch is used to improve the existing command, which adds an
option "-c"
> to the the command "runq". The option "-c" displays the timestamp
information about
> the runqueue each of cpu. The timstamp information, which accordings to
the kernel
> version you use, may be the value of runqueue's member. for example,
rq.clock or
> rq.timestamp_last_tick, even runqueue.timestamp_last_tick.
> 	Besides, I have already tested it on rhel4.8/rehl5.7/rhel6.2,
without any error.
> 	The result like this:
> >    crash> runq -c
> >    CPU 0: 66789719522523
> >    CPU 1: 66789719628339
> >    CPU 2: 66789719519625
> 
> Regards,
> Wei Jiangang

Wei,

What is the debugging scenario that you feel the need to know the
timestamp of each cpu's runqueue?  Perhaps you want to compare it to
the "ps -l" output?  

Dave

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