Re: Wrong Perf Backtraces

[ahmadkhorrami <ahmadkhorrami@ut.ac.ir>]

Sorry. GDB should disassemble functions so that the names are not 
demangled.

On 2020-03-26 22:49, ahmadkhorrami wrote:

> Hi,
> Here is the link for the python script:
> https://gofile.io/?c=1ZSLwe
> It is written in python-3 and takes the perf script output as input.
> It looks for consecutive repeated backtrace lines and checks if the 
> function in these lines calls itself at the offset in the line (i.e., 
> checks if recursion is possible). If not possible it reports an error. 
> Could you check to see if any error is detected in your outputs, 
> please?
> Regards.
> On 2020-03-26 20:09, Jiri Olsa wrote:
> 
> On Thu, Mar 26, 2020 at 05:50:27PM +0430, ahmadkhorrami wrote:
> 
> Hi,
> First of all, many thanks for your time. Did you say that the first 
> file has
> problems?
> 
> The first file (http://gofile.io/?c=qk6oXv) has repeated gmallocn()s 
> while
> the second (https://gofile.io/?c=oGxgSM) also has problems with 
> unmatched
> (not necessarily repeated) function calls. I am not sure if the kernel 
> for
> the second one is 5.4.7 or the generic Ubuntu kernel. But the first one 
> is
> certainly 5.4.7. Just to be clear, there were many instances of these
> unmatched <caller, callees>.
> I can se all the files, but I just can't see the issue yet
> but it's probably because of issues with perf archive..
> 
> let's see if somebody else can chime in
> 
> I have a simple python script that checks for this situation. It
> disassembles functions using GDB and checks the (directly called) 
> target of
> each caller. I will put some comments in the script and upload it. 
> Could you
> check to see if the python script detects any mismatches in your 
> backtraces?
> It takes the perf script output file as input. I will upload the script 
> in
> an hour.
> ok
> 
> jirka