Probing symbols that are not EXPORT()ed

Alan David Brunelle Alan.Brunelle@hp.com
Thu Jun 8 19:03:00 GMT 2006


[Sorry for this newbie question...]

How does one probe on a kernel function that does not have an

EXPORT_SYMBOL()

invocation?

For example the following fails:

global rqs

probe kernel.function("scsi_dispatch_cmd")
{
        rqs <<< $cmd->request_bufflen
}

probe end
{
        print(@hist_linear(rqs, 0, 512000, 4000))
        exit()
}

with:

[root@bl25p1 06_08]# stap -v scwrite.stp
Pass 1: parsed user script and 11 library script(s) in 40usr/0sys/51real ms.
semantic error: no match for probe point
         while: resolving probe point kernel.function("scsi_dispatch_cmd")
Pass 2: analyzed script: 1 probe(s), 4 function(s), 1 global(s) in 
150usr/20sys/163real ms.
Pass 2: analysis failed.

Thanks,
Alan



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