Re: [PATCH v2] ftrace: Fix stack trace entry generated by ftrace_pid_func()

From: Tatsuya S
Date: Mon May 27 2024 - 22:55:47 EST


On Mon, May 27, 2024 at 07:49:14PM GMT, Steven Rostedt wrote:
> On Mon, 27 May 2024 18:44:56 +0900
> Tatsuya S <tatsuya.s2862@xxxxxxxxx> wrote:
>
> > On setting set_ftrace_pid, a extra entry generated by ftrace_pid_func()
> > is shown on stack trace(CONFIG_UNWINDER_FRAME_POINTER=y).
> >
> > [004] ..... 68.459382: <stack trace>
> > => 0xffffffffa00090af
> > => ksys_read
> > => __x64_sys_read
> > => x64_sys_call
> > => do_syscall_64
> > => entry_SYSCALL_64_after_hwframe
> >
> > To resolve this issue, increment skip count
> > in function_stack_trace_call() if pids are set.
>
> Just a note, this isn't a "fix" but simply an improvement in output.
> I'm happy to take this (after testing and more reviewing), but it will
> be for the next merge window, and with a different subject line.
>
> "ftrace: Hide one more entry in stack trace when ftrace_pid is enabled"
>
> Or something like that.
>
> Thanks,
>
> -- Steve
I will send patch with new subject line.

Thank you.

Tatsuya