stapbpf(8) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | ARGUMENTS | EXAMPLES | LIMITATIONS | SAFETY AND SECURITY | SEE ALSO | BUGS | COLOPHON

STAPBPF(8)               System Manager's Manual              STAPBPF(8)

NAME         top

       stapbpf - systemtap bpf runtime

SYNOPSIS         top

       stapbpf [ OPTIONS ] MODULE

DESCRIPTION         top

       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)

OPTIONS         top

       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.

ARGUMENTS         top

       MODULE is the path of a bpf-elf file produced by the front-end
       stap tool, when run with --runtime=bpf.

EXAMPLES         top

       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.

LIMITATIONS         top

       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 information 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
       functions.

       The name of the bpf-elf file produced by the front-end stap tool
       should not be changed.

SAFETY AND SECURITY         top

       See the stap(1) manual page for additional information on safety
       and security.

SEE ALSO         top

       stap(1), stapprobes(3stap), staprun(8), stapex(3stap)

BUGS         top

       Use the Bugzilla link of the project web page or our mailing
       list.  http://sourceware.org/systemtap/ ,
       <systemtap@sourceware.org>.

COLOPHON         top

       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 2021-08-27.  (At that
       time, the date of the most recent commit that was found in the
       repository was 2021-08-26.)  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)