Re: [PATCH] rcu: ftrace: avoid tracing a few functions executed in multi_cpu_stop()

[Steven Rostedt]

On Fri, 22 Apr 2022 18:45:46 +0800
patrick wang <patrick.wang.shcn@xxxxxxxxx> wrote:

> Yes, and not just RISC-V. It's arch-independent. It's the internal change of
> stop machine implementation.
> 
> ----------------------------------------------------------------
> Former stop machine wait loop:
> do {
>     cpu_relax(); => macro
>     ...
> } while (curstate != STOPMACHINE_EXIT);
> -----------------------------------------------------------------
> Current stop machine wait loop:
> do {
>     stop_machine_yield(cpumask); => function (notraced)
>     ...
>     touch_nmi_watchdog(); => function (notraced, inside calls also notraced)
>     ...
>     rcu_momentary_dyntick_idle(); => function (notraced, inside calls traced)
> } while (curstate != MULTI_STOP_EXIT);
> ------------------------------------------------------------------

That makes much more sense. Can you add that to the change log.

Reviewed-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx>

-- Steve