[lttng-dev] Capturing User-Level Function Calls/Returns

[Frank Ch. Eigler]

Hi -

> If you can afford a more invasive tool, that requires a lot of
> memory and stops your application for quite some time, you can look
> at approaches like dyninst that decompile the binary, insert
> instrumentation code and reassemble the code.

> https://dyninst.org/

For the record, systemtap includes a backend that uses dyninst as a
pure userspace backend.


% cat foo.c
#include <stdio.h>

int foo() {
  printf("foo\n");
  return 1;
}

int main() {
  foo();
}

% gcc -g foo.c

% stap --runtime=dyninst -e '
   probe process.function("*").{call,return} { println(pp()) }
' -c a.out

foo
process("/home/fche/a.out").function("main@/home/fche/foo.c:8").call
process("/home/fche/a.out").function("foo@/home/fche/foo.c:3").call
process("/home/fche/a.out").function("foo@/home/fche/foo.c:3").return
process("/home/fche/a.out").function("main@/home/fche/foo.c:8").return


- FChE