Re: Wrong Perf Backtraces

On Fri, Mar 27, 2020 at 11:13:27PM +0430, ahmadkhorrami wrote:
> Hi,
> I revised the code. Hopefully, it works. Could you check it with your own
> outputs? It is valuable for me to know if your output contains wrong
> backtraces or not. Here is the link:
> https://gofile.io/?c=rz2kGc

will check, so far caught one.. might be same case:

evince 2168454 1549196.055094:      43831 cycles:u:
  ffffffffaec012f0 [unknown] ([unknown])
      7f0dd44776b6 __mmap64+0x26 (inlined)
      7f0dd44776b6 __mmap64+0x26 (inlined)

will try to investigate next week

thanks,
jirka

> Regards.
> 
> On 2020-03-27 15:34, 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'.
> > 
> > Regards.
> > 
> > On 2020-03-27 15:29, ahmadkhorrami wrote:
> > 
> > > Hi,
> > > Thanks! Could you tell me what should be changed in order to make
> > > the code runnable on your system, if it is possible?
> > > Regards.
> > > 
> > > On 2020-03-27 13:50, Jiri Olsa wrote:
> > > 
> > > On Thu, Mar 26, 2020 at 10:49:12PM +0430, 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?
> > > I'm getting tons of following output:
> > > 
> > > /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.30: No such file or
> > > directory.
> > > No symbol table is loaded.  Use the "file" command.
> > > 7ffff71b9bc1 gtk_css_node_invalidate_timestamp+0x31
> > > (/usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.30)
> > > 
> > > I assume it's because I have all the dso binaries stored
> > > under .biuldid path, while you check the output name
> > > 
> > > jirka
> > > 
> > > 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
>