I'm trying to learn how to use SystemTap, but I currently fail at even running the examples provided by the systemtap-docs package:
Code:
# stap /usr/share/doc/packages/systemtap/examples/process/schedtimes.stp
semantic error: while resolving probe point: identifier 'kernel' at /usr/share/doc/packages/systemtap/examples/process/schedtimes.stp:34:7
source: probe kernel.trace("sched_switch") {
^
semantic error: no match
semantic error: while resolving probe point: identifier 'kernel' at :105:7
source: probe kernel.trace("sched_wakeup") {
^
WARNING: cannot find module /tmp/stapmft4Pc/typequery_kmod_1/typequery_kmod_1.ko debuginfo: Unsupported relocation type
WARNING: cannot find module /root/.systemtap/cache/99/typequery_99c4493878436ab6976588e4e37d9622_708.ko debuginfo: Unsupported relocation type
Pass 2: analysis failed. Try again with another '--vp 01' option.
Indeed, stap seems to indicate that there are no kernel tracepoints defined on my system:
Code:
# stap -L 'kernel.trace("*")'
returns nothing.
Generally, stap seems to be installed correctly on my openSUSE 12.2, as a simple check script runs as expected:
Code:
# stap -e 'probe vfs.read { printf("vfs.read\n"); exit() }'
WARNING: cannot find module nfs debuginfo: Unsupported relocation type
WARNING: cannot find module sunrpc debuginfo: Unsupported relocation type
vfs.read
I can see the trace events in debugfs:
Code:
# ls -l /sys/kernel/debug/tracing/events/sched/sched_wakeup
total 0
-rw-r--r-- 1 root root 0 Jan 23 14:59 enable
-rw-r--r-- 1 root root 0 Jan 23 14:59 filter
-r--r--r-- 1 root root 0 Jan 23 14:59 format
-r--r--r-- 1 root root 0 Jan 23 14:59 id
My Google-fu fails me. Does anyone here have an idea what I could do to successfully use kernel tracepoints in SystemTap?
Thanks in advance!
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