Re: [PATCH V2 1/2] tracing/timerlat: Notify new max thread latency

From: Steven Rostedt
Date: Wed Mar 29 2023 - 12:15:55 EST


On Wed, 29 Mar 2023 17:50:15 +0200
Daniel Bristot de Oliveira <bristot@xxxxxxxxxx> wrote:

> timerlat is not reporting a new tracing_max_latency for the thread
> latency. The reason is that it is not calling notify_new_max_latency()
> function after the new thread latency is sampled.
>
> Call notify_new_max_latency after computing the thread latency.
>
> Changes from V1:
> Split the patch into two patches (Steve)

FYI, when doing this, please place the updates below the "---"

That way it doesn't automatically end up in the git log, and I have to go
back in and remove it.

>
> Fixes: dae181349f1e ("tracing/osnoise: Support a list of trace_array *tr")
> Cc: Daniel Bristot de Oliveira <bristot@xxxxxxxxxx>
> Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
> Cc: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
> Signed-off-by: Daniel Bristot de Oliveira <bristot@xxxxxxxxxx>
> ---

Here, you can add:

Changes from V1: https://lore.kernel.org/linux-trace-kernel/c22302a7db3cee6bcabf87462ed22a35dd38690f.1679675521.git.bristot@xxxxxxxxxx/
Split the patch into two patches (Steve)

Notice, that I also added the link to the previous version, so it's easy to
find if someone wanted to investigate this series.

-- Steve



> kernel/trace/trace_osnoise.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/kernel/trace/trace_osnoise.c b/kernel/trace/trace_osnoise.c
> index 9176bb7a9bb4..e8116094bed8 100644
> --- a/kernel/trace/trace_osnoise.c
> +++ b/kernel/trace/trace_osnoise.c
> @@ -1738,6 +1738,8 @@ static int timerlat_main(void *data)
>
> trace_timerlat_sample(&s);
>
> + notify_new_max_latency(diff);
> +
> timerlat_dump_stack(time_to_us(diff));
>
> tlat->tracing_thread = false;