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NAME | SYNOPSIS | DESCRIPTION | OPTIONS | ARGUMENTS | EXAMPLES | LIMITATIONS | SAFETY AND SECURITY | SEE ALSO | BUGS | COLOPHON |
STAPBPF(8) System Manager's Manual STAPBPF(8)
stapbpf - systemtap bpf runtime
stapbpf [ OPTIONS ] MODULE
The stapbpf program is the BPF back-end of the Systemtap tool. It
expects a bpf-elf file produced by the front-end stap tool, when run
with --runtime=bpf.
Splitting the systemtap tool into a front-end and a back-end allows a
user to compile a systemtap script on a development machine that has
the debugging information needed to compile the script and then
transfer the resulting shared object to a production machine that
doesn't have any development tools or debugging information
installed.
Please refer to stappaths(7) for the version number, or run
$ rpm -q systemtap # (for Fedora/RHEL)
$ apt-get -v systemtap # (for Ubuntu)
The stapbpf program supports the following options. Any other option
prints a list of supported options.
-v Verbose mode.
-V Print version number and exit.
-w Suppress warnings from the script.
-h Print help message.
-x PID The '_stp_target' variable will be set to PID.
-o FILE
Send output to FILE.
MODULE is the path of a bpf-elf file produced by the front-end stap
tool, when run with --runtime=bpf.
Here is a very basic example of how to generate a stapbpf module.
First, use stap to compile a script. The stap program will report
the name of the resulting module in the current working directory.
$ stap --runtime=bpf -p4 -e 'probe begin { printf("Hello World!\n");
exit() }'
stap_28784.bo
Run stapbpf with the pathname to the module as an argument.
$ stapbpf ./stap_28784.bo
Hello World!
If the -p4 option is omitted, stap will invoke stapbpf automatically.
This runtime is in an early stage of development and it currently
lacks support for a number of features available in the default
runtime. A subset of the following probe points is supported:
begin
end
kernel.*
process.*
timer.*
perf.*
procfs.*
In general, probes based on the kprobes, uprobes, tracepoint and perf
infrastructures are supported. See stapprobes(3stap) for more infor‐
mation on the probe points and which tracing infrastructures they are
based on.
for loops, foreach loops and while loops are usable only in begin and
end probes. try statements are not supported.
There is limited support for string operations. String variables and
literals are limited to 64 characters, except for printf format
strings, which are limited to 256 characters.
A subset of the statistical aggregate functionality is available,
with support only for the @count(), @sum(), @avg() extractor func‐
tions.
The name of the bpf-elf file produced by the front-end stap tool
should not be changed.
See the stap(1) manual page for additional information on safety and
security.
stap(1), stapprobes(3stap), staprun(8), stapex(3stap)
Use the Bugzilla link of the project web page or our mailing list.
http://sourceware.org/systemtap/ , <systemtap@sourceware.org>.
This page is part of the systemtap (a tracing and live-system
analysis tool) project. Information about the project can be found
at ⟨https://sourceware.org/systemtap/⟩. If you have a bug report for
this manual page, send it to systemtap@sourceware.org. This page was
obtained from the project's upstream Git repository
⟨git://sourceware.org/git/systemtap.git⟩ on 2020-08-13. (At that
time, the date of the most recent commit that was found in the repos‐
itory was 2020-08-07.) If you discover any rendering problems in
this HTML version of the page, or you believe there is a better or
more up-to-date source for the page, or you have corrections or
improvements to the information in this COLOPHON (which is not part
of the original manual page), send a mail to man-pages@man7.org
STAPBPF(8)
Pages that refer to this page: stap(1)