Re: Re: Fw: Re: Re: Howto make perf probe work

[OSDepend <osdepend@gmail.com>]

Hi Kim,

> > >HI,
> > >Please enable kprobe_event config option in the kernel and build the same
> > >and boot the board using it. Then please try to add event using perf probe
> > >command
> > 
> > Thanks very much for your reply, and I already enable DEBUG_KPROBE_EVENT in kernel.
> > I did success in "perf probe handle_mm_fault".
> > 
> > But when i want to to "perf probe" other Kernel symbol, such as do_page_fault.
> > I came across other problems:
> >     Added new event:
> >     Failed to write event: Invalid argument
> >     Error: Failed to add events. (-1)
> > And when i type perf probe page_fault_entry:
> >     Kernel symbol 'page_fault_entry' not found.
> >     Error: Failed to add events. (-2)
> > Please notice that "do_page_fault" and "page_fault_entry" are all Kernel symbols, which canbe find in  "/proc/kallsyms", but not recorgonized by perf (or even kprobe).
> > Any idea for that?
> For some reason, do_page_fault() is marked as __kprobe on some arch
> which means it cannot be probed.
> Thanks,
> Namhyung

My kernel is runing on X86_64 arch, is there any chance for me to get the do_page_fault() entry/exit work?
Or How can i add a exit tracepoint for handle_mm_fault()? so I can calculate the latency of that fault handle function?

Best,
Chen