Re: [PATCH] tracing/osnoise: Use built-in RCU list checking

[Daniel Bristot de Oliveira <bristot@kernel.org>]

On 12/27/22 03:30, Chuang Wang wrote:
> list_for_each_entry_rcu() has built-in RCU and lock checking.
> 
> Pass cond argument to list_for_each_entry_rcu() to silence false lockdep
> warning when CONFIG_PROVE_RCU_LIST is enabled.
> 
> Execute as follow:
> 
>  [tracing]# echo osnoise > current_tracer
>  [tracing]# echo 1 > tracing_on
>  [tracing]# echo 0 > tracing_on
> 
> The trace_types_lock is held when osnoise_tracer_stop() or
> timerlat_tracer_stop() are called in the non-RCU read side section.
> So, pass lockdep_is_held(&trace_types_lock) to silence false lockdep
> warning.
> 
> Fixes: dae181349f1e ("tracing/osnoise: Support a list of trace_array *tr")
> Signed-off-by: Chuang Wang <nashuiliang@gmail.com>

Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org>

Thanks!
-- Daniel