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Re: Command line arg for kernel Tracepoints
On Mon, 2011-01-03 at 20:02 +0530, h patel wrote:
> Hi Mark,
>
> tpoint is the global variable. I want to enable disable tracepoints
> at runtime.
> Adrien suggested following way :
>
> global tpoint = "whateverDefaultProbeYouLike"
> probe kernel.trace(tpoint) { printf("oh hai\n") }
>
> # stap -m test test.stp
> # staprun test.ko tpoint="anotherTracepoint"
>
> I tried kernel.trace(tpoint), kernel.trace($tpoint),
> kernel.trace("tpoint"), none of them worked.
Aha. Sorry, I had misunderstood what you were trying to do. Apologies.
Something like the following should work for that use case:
$ stap -e 'probe kernel.trace(@1) { log(pp()); exit();}' "sys_enter"
kernel.trace("sys_enter")
$ stap -e 'probe kernel.trace(@1) { log(pp()); exit();}' "timer_start"
kernel.trace("timer_start")
Cheers,
Mark