Re: [PATCH v2] cpuidle: psci: Add trace for PSCI domain idle

[Steven Rostedt]

On Mon, 20 Jan 2025 09:36:16 +0800
Keita Morisaki <keyz@xxxxxxxxxx> wrote:

> The trace event cpu_idle provides insufficient information for debugging
> PSCI requests due to lacking access to determined PSCI domain idle
> states. The cpu_idle usually only shows -1, 0, or 1 regardless how many
> idle states the power domain has.
> 
> Add new trace events namely psci_domain_idle_enter and
> psci_domain_idle_exit to trace enter and exit events with a determined
> idle state.
> 
> These new trace events will help developers debug CPUidle issues on ARM
> systems using PSCI by providing more detailed information about the
> requested idle states.
> 
> Signed-off-by: Keita Morisaki <keyz@xxxxxxxxxx>
> ---
> v1->v2: Split the ftrace event into two (psci_domain_idle_(enter|exit))
> 		and rephrase the commit message accordingly. Rebased onto the latest.
> 
>  drivers/cpuidle/cpuidle-psci.c |  3 +++
>  include/trace/events/power.h   | 37 ++++++++++++++++++++++++++++++++++
>  2 files changed, 40 insertions(+)

From the tracing point of view, there's nothing that sticks out that is incorrect.

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

As for if it should be applied, that's for the maintainers of the subsystem
that it exists in.

-- Steve