Re: Wrong Perf Backtraces

Hi,
Thanks Milian. So if I am right, I should do the following:
1) Run "perf buildid-list" and catch all the <file path, build-ids> 
pairs.
2) First check for the existence of the file path.
3) If failed, concatenate "~/.debug", file path, "/" and buildid and use 
it as the alternative.
I thought that GDB is smart enough to detect these situations in the 
same way that it detects debug info files.
Should I check any directory other than ~/.debug?
Regards.

On 2020-03-27 16:40, Milian Wolff wrote:

> On Freitag, 27. März 2020 12:04:20 CET ahmadkhorrami wrote:
> 
>> I do the following:
>> If this line is in the perf script backtrace:
>> 7f21ffe256db g_main_context_iteration+0x2b
>> (/usr/lib/x86_64-linux-gnu/libglib-2.0.so.0.5600.4)
>> I run the following command:
>> gdb -batch -ex 'file 
>> /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0.5600.4'
>> -ex 'disass g_main_context_iteration'.
> 
> You can try to parse the output of `perf buildid-list` to get a mapping 
> that
> can be used to run this on another person's machine. E.g.
> 
> ```
> $ perf buildid-list
> 5837b1e7495db791f9a3a56fb6ca29958da75b0c [kernel.kallsyms]
> 845f98f6a3019620c37a2f611b2f20c27de83d5b 
> /home/milian/projects/kdab/rnd/
> hotspot/build/tests/test-clients/cpp-parallel/cpp-parallel
> f6ca5853dae87d9f0503a9ef230f6d1fa15a832d /usr/lib/ld-2.30.so
> 92883b06055e8e21ded8eb0cd5a61f5704531152 [vdso]
> 8b04d1825b63d9a600e3d57ac71058935e7ad757 /usr/lib/libpthread-2.30.so
> 09639b80a8fad179004f2484608764d2b336dd4a /usr/lib/libstdc++.so.6.0.27
> 33d1f350f13728651d74dd2a56bad1e4e4648f5e /usr/lib/libc-2.30.so
> $ file 
> ~/.debug/usr/lib/ld-2.30.so/f6ca5853dae87d9f0503a9ef230f6d1fa15a832d/
> elf
> /home/milian/.debug/usr/lib/ld-2.30.so/
> f6ca5853dae87d9f0503a9ef230f6d1fa15a832d/elf: ELF 64-bit LSB shared 
> object,
> x86-64, version 1 (SYSV), statically linked,
> BuildID[sha1]=f6ca5853dae87d9f0503a9ef230f6d1fa15a832d, not stripped
> ```
> 
> I'm afraid to say that I currently don't have the time required to be 
> of more
> help in debugging this issue in general.
> 
> Good luck!