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

[ahmadkhorrami]

Hi Frank,

Thanks for the point!

Regards.


On 2020-07-16 06:19, Frank Ch. Eigler wrote:

> 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